Patent Publication Number: US-11049448-B2

Title: Memory-in-pixel architecture

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Patent Application No. 62/668,707, entitled “MEMORY-IN-PIXEL ARCHITECTURE,” filed on May 8, 2018, which is incorporated herein by reference in its entirety for all purposes. 
    
    
     SUMMARY 
     A summary of certain embodiments disclosed herein is set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of these certain embodiments and that these aspects are not intended to limit the scope of this disclosure. Indeed, this disclosure may encompass a variety of aspects that may not be set forth below. 
     Methods and systems for reducing bandwidths, or amounts simultaneously transmitted, of image data transmitted and processed to prepare an image for presentation on an electronic display by implementing memory in pixels of the electronic display may provide immense value. Such an implementation of memory in the pixels may permit an elimination of a frame buffer associated with the electronic display. Having memory in the pixels may lessen the design complexity of electronic displays, as well, because the less image data that is concurrently transmitted to a pixel array of an electronic display, the simpler an electronic display may be designed. For example, the pixels may be programmed in smaller groups because memory in the pixel stores the values until a time of presentation of the image. 
     This disclosure describes an electronic display having one or more pixels that include memory and a driver that may help to decrease a bandwidth associated with transmitting and processing image data for presentation on an electronic display. The inclusion of the memory in the pixel may enable storage of image data prior to output to a light-emitting portion of the pixel. Thus, the memory in the pixel may reduce, or in some instances eliminate, a reliance upon a frame buffer in an electronic display by acting as an individual frame buffer for the pixel. The memory in the pixel may be used in conjunction with a driver to cause a light-emitting portion of the pixel to emit light. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various aspects of this disclosure may be better understood upon reading the following detailed description and upon reference to the drawings in which: 
         FIG. 1  is a schematic block diagram of an electronic device, in accordance with an embodiment; 
         FIG. 2  is a perspective view of a watch representing an embodiment of the electronic device of  FIG. 1 , in accordance with an embodiment; 
         FIG. 3  is a front view of a tablet device representing an embodiment of the electronic device of  FIG. 1 , in accordance with an embodiment; 
         FIG. 4  is a front view of a computer representing an embodiment of the electronic device of  FIG. 1 , in accordance with an embodiment; 
         FIG. 5  is a block diagram of a display system of the electronic device of  FIG. 1 , in accordance with an embodiment; 
         FIG. 6  is a block diagram of a pixel array of the display system of  FIG. 5 , in accordance with an embodiment; 
         FIG. 7  is a block diagram of an embodiment of the pixel array of  FIG. 6 , in accordance with an embodiment; 
         FIG. 8  is a block diagram of a pixel of the pixel array of  FIG. 6  that emits light according to a binary pulse width modulation emission scheme, in accordance with an embodiment; 
         FIG. 9  is a block diagram of an embodiment of the pixel of the pixel array of  FIG. 6  that emits light according to a single pulse width modulation emission scheme, in accordance with an embodiment; 
         FIG. 10  is a block diagram of another embodiment of the pixel of the pixel array of  FIG. 6  that emits light according to a pulse density modulation emission scheme, in accordance with an embodiment; 
         FIG. 11  is a timing diagram of programming sequences performed by a column driver of the display system of  FIG. 5 , in accordance with an embodiment; 
         FIG. 12  is a circuit diagram of a first embodiment of a sub-pixel of the pixel array of  FIG. 6  having a current drive, in accordance with an embodiment; 
         FIG. 13  is a circuit diagram of a second embodiment of the sub-pixel of the pixel array of  FIG. 6  having a hybrid drive and having memory, in accordance with an embodiment; 
         FIG. 14  is a timing diagram of control signals used to operate the sub-pixel of  FIG. 13 , in accordance with an embodiment; 
         FIG. 15  is a graph showing a current and a voltage created by simulating transmission of image data corresponding to a binary pulse width modulated emission scheme to the sub-pixel of  FIG. 12 , in accordance with an embodiment; 
         FIG. 16  is a graph showing a current and a voltage created by simulating transmission of image data corresponding to a binary pulse width modulated emission scheme to the sub-pixel of  FIG. 13 , in accordance with an embodiment; 
         FIG. 17  is a circuit diagram of memory circuitry coupled to the sub-pixel of  FIG. 12 , in accordance with an embodiment; 
         FIG. 18  is a circuit diagram of an embodiment of the memory circuitry of  FIG. 17  coupled to an embodiment of a sub-pixel of  FIG. 12  implementing a global anode, in accordance with an embodiment; 
         FIG. 19  is a process for operating the sub-pixel of  FIG. 18 , in accordance with an embodiment; 
         FIG. 20  is a circuit diagram of an embodiment of the sub-pixel of  FIG. 18  implementing a global cathode, in accordance with an embodiment; 
         FIG. 21  is a circuit diagram of an embodiment of the memory circuitry of  FIG. 13 , in accordance with an embodiment; 
         FIG. 22  is a process for operating the memory circuitry of  FIG. 21 , in accordance with an embodiment; 
         FIG. 23  is a circuit diagram of an embodiment of the memory circuitry of  FIG. 13 , in accordance with an embodiment; 
         FIG. 24A  is a bit-plane graph corresponding to no reordering implemented in the memory circuitry of  FIG. 23 , in accordance with an embodiment; 
         FIG. 24B  is an error graph corresponding to no reordering implemented in the memory circuitry of  FIG. 23 , in accordance with an embodiment; 
         FIG. 24C  is a bit-plane graph corresponding to two reorderings implemented in the memory circuitry of  FIG. 23 , in accordance with an embodiment; 
         FIG. 24D  is an error graph corresponding to two reorderings implemented in the memory circuitry of  FIG. 23 , in accordance with an embodiment; 
         FIG. 24E  is a bit-plane graph corresponding to three reorderings implemented in the memory circuitry of  FIG. 23 , in accordance with an embodiment; 
         FIG. 24F  is an error graph corresponding to three reorderings implemented in the memory circuitry of  FIG. 23 , in accordance with an embodiment; 
         FIG. 24G  is a bit-plane graph corresponding to an ideal case of reordering implemented in the memory circuitry of  FIG. 23 , in accordance with an embodiment; 
         FIG. 24H  is an error graph corresponding to an ideal case of reordering implemented in the memory circuitry of  FIG. 23 , in accordance with an embodiment; 
         FIG. 25  is a bit-plane graph illustrating the bit-plane graph of  FIG. 24C  over time and with an inclusion of additional color channels, in accordance with an embodiment; 
         FIG. 26  is a timing diagram illustrating a loading and emission process associated with a third quadrant of the bit-plane graph of  FIG. 25 , in accordance with an embodiment; 
         FIG. 27  is a circuit diagram of an embodiment of the memory circuitry of  FIG. 23  implemented for use in a digital mirror display, in accordance with an embodiment; 
         FIG. 28  is a circuit diagram of an embodiment of the pixel of  FIG. 25  for use in a liquid crystal display, in accordance with an embodiment; 
         FIG. 29  is a block diagram comparing the display system of  FIG. 5  with a display system having a smart buffer outside of an active area of the electronic display, in accordance with an embodiment; 
         FIG. 30  is a circuit diagram of an embodiment of the memory circuitry of  FIG. 13  for use in the smart buffer of  FIG. 29 , in accordance with an embodiment; and 
         FIG. 31  is a circuit diagram of a third embodiment of sub-pixel of the pixel array of  FIG. 6  for use in the display system having the smart buffer of  FIG. 29 , in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS 
     One or more specific embodiments will be described below. In an effort to provide a concise description of these embodiments, not all features of an actual implementation are described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers&#39; specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure. 
     When introducing elements of various embodiments of the present disclosure, the articles “a,” “an,” and “the” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. Additionally, it should be understood that references to “one embodiment” or “an embodiment” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. 
     Electronic displays are found in numerous electronic devices, from mobile phones to computers, televisions, automobile dashboards, and many more. Electronic displays have achieved increasingly higher resolutions by reducing individual pixel size. Yet increasing resolutions may increase a difficultly associated with managing an increased amount of image data associated with the increased resolutions processed by processing circuitry prior to displaying an image, for example, by causing increased power consumption from processing increased amounts of image data. Furthermore, the increasing resolutions may increase a bandwidth used to communicate image data from the processing circuitry to a pixel array for presentation of the image because more image data is used to communicate the same image at a higher electronic display resolution. 
     Embodiments of the present disclosure relate to systems and methods for implementing memory-in-pixel circuitry that may be used as an individual frame buffer for each pixel, which may reduce reliance on a frame buffer external to a pixel array and driving circuitry of an electronic display. Memory may be implemented in pixel circuitry that includes a light-emitting diode (LED). An organic light-emitting diode (OLED) represents one type of LED that may be found in the pixel, but other types of LEDs may also be used or light-emitting components may be used in the pixel circuitry, such as components to support liquid crystal displays (LCDs), plasma display panels, and/or dot-matrix displays. 
     The systems and methods of this disclosure to implement memory-in-pixel circuitry may reduce transmission bandwidths of image data to pixel arrays for display because the pixel may store image data in the memory. In this way, a reliance on frame buffers to temporarily store the image data external to the pixel is reduced because the pixel has its own memory to store its own image data prior to display of the image data. 
     A general description of suitable electronic devices that may include a self-emissive display, such as a LED (e.g., an OLED) display, and corresponding circuitry of this disclosure are provided. An OLED represents one type of LED that may be found in the self-emissive pixel, but other types of LEDs may also be used. 
     To help illustrate, an electronic device  10  including an electronic display  18  is shown in  FIG. 1 . As is described in more detail below, the electronic device  10  may be any suitable electronic device, such as a computer, a mobile phone, a portable media device, a tablet, a television, a virtual-reality headset, a vehicle dashboard, and the like. Thus, it should be noted that  FIG. 1  is merely one example of a particular implementation and is intended to illustrate the types of components that may be present in an electronic device  10 . The electronic device  10  may include, among other things, a processing core complex  12  such as a system on a chip (SoC) and/or processing circuit(s), storage device(s)  14 , communication interface(s)  16 , the electronic display  18 , input structures  20 , and a power supply  22 . The various components described in  FIG. 1  may include hardware elements (e.g., circuitry), software elements (e.g., a tangible, non-transitory computer-readable medium storing instructions), or a combination of both hardware and software elements. It should be noted that the various depicted components may be combined into fewer components or separated into additional components. 
     As depicted, the processing core complex  12  is operably coupled with the storage device(s)  14 . Thus, the processing core complex  12  execute instructions stored in the storage device(s)  14  to perform operations, such as generating and/or transmitting image data. As such, the processing core complex  12  may include one or more general purpose microprocessors, one or more application specific integrated circuits (ASICs), one or more field programmable logic arrays (FPGAs), or any combination thereof. Using pixels containing light-emitting components (e.g., LEDs, OLEDs), the electronic display  18  may show images generated by the processing core complex  12 . 
     In addition to instructions, the storage device(s)  14  may store data to be processed by the processing core complex  12 . Thus, in some embodiments, the storage device(s)  14  may include one or more tangible, non-transitory, computer-readable mediums. The storage device(s)  14  may be volatile and/or non-volatile. For example, the storage device(s)  14  may include random access memory (RAM) and/or read only memory (ROM), rewritable non-volatile memory such as flash memory, hard drives, optical discs, and/or the like, or any combination thereof. 
     As depicted, the processing core complex  12  is also operably coupled with the communication interface(s)  16 . In some embodiments, the communication interface(s)  16  may facilitate communicating data with another electronic device and/or a network. For example, the communication interface(s)  16  (e.g., a radio frequency system) may enable the electronic device  10  to communicatively couple to a personal area network (PAN), such as a Bluetooth network, a local area network (LAN), such as an 1622.11x Wi-Fi network, and/or a wide area network (WAN), such as a 4G or Long-Term Evolution (LTE) cellular network. 
     Additionally, as depicted, the processing core complex  12  is also operably coupled to the power supply  22 . In some embodiments, the power supply  22  may provide electrical power to one or more components in the electronic device  10 , such as the processing core complex  12  and/or the electronic display  18 . Thus, the power supply  22  may include any suitable source of energy, such as a rechargeable lithium polymer (Li-poly) battery and/or an alternating current (AC) power converter. 
     As depicted, the electronic device  10  is also operably coupled with the one or more input structures  20 . In some embodiments, an input structure  20  may facilitate user interaction with the electronic device  10 , for example, by receiving user inputs. Thus, the input structures  20  may include a button, a keyboard, a mouse, a trackpad, and/or the like. Additionally, in some embodiments, the input structures  20  may include touch-sensing components in the electronic display  18 . In such embodiments, the touch sensing components may receive user inputs by detecting occurrence and/or position of an object touching the surface of the electronic display  18 . 
     In addition to enabling user inputs, the electronic display  18  may include a display panel with one or more display pixels. As described above, the electronic display  18  may control light emission from the display pixels to present visual representations of information, such as a graphical user interface (GUI) of an operating system, an application interface, a still image, or video content, by displaying frames based at least in part on corresponding image data. As depicted, the electronic display  18  is operably coupled to the processing core complex  12 . In this manner, the electronic display  18  may display frames based at least in part on image data generated by the processing core complex  12 . Additionally or alternatively, the electronic display  18  may display frames based at least in part on image data received via the communication interface(s)  16  and/or the input structures  20 . 
     As may be appreciated, the electronic device  10  may take a number of different forms. As shown in  FIG. 2 , the electronic device  10  may take the form of a watch  30 . For illustrative purposes, the watch  30  may be any Apple Watch® model available from Apple Inc. As depicted, the watch  30  includes an enclosure  32  (e.g., housing). In some embodiments, the enclosure  32  may protect interior components from physical damage and/or shield them from electromagnetic interference (e.g., house components). A strap  34  may enable the watch  30  to be worn on the arm or wrist. The electronic display  18  may display information related to the operation of the watch  30 . Input structures  20  may enable the user to activate or deactivate watch  30 , navigate a user interface to a home screen, navigate a user interface to a user-configurable application screen, activate a voice-recognition feature, provide volume control, and/or toggle between vibrate and ring modes. As depicted, the input structures  20  may be accessed through openings in the enclosure  32 . In some embodiments, the input structures  20  may include, for example, an audio jack to connect to external devices. 
     The electronic device  10  may also take the form of a tablet device  40 , as shown in  FIG. 3 . For illustrative purposes, the tablet device  40  may be any iPad® model available from Apple Inc. Depending on the size of the tablet device  40 , the tablet device  40  may serve as a handheld device such as a mobile phone. The tablet device  40  includes an enclosure  42  through which input structures  20  may protrude. In certain examples, the input structures  20  may include a hardware keypad (not shown). The enclosure  42  also holds the electronic display  18 . The input structures  20  may enable a user to interact with a GUI of the tablet device  40 . For example, the input structures  20  may enable a user to type a Rich Communication Service (RCS) text message, a Short Message Service (SMS) text message, or make a telephone call. A speaker  44  may output a received audio signal and a microphone  46  may capture the voice of the user. The tablet device  40  may also include a communication interface  16  to enable the tablet device  40  to connect via a wired connection to another electronic device. 
       FIG. 4  illustrates a computer  48 , which represents another form that the electronic device  10  may take. For illustrative purposes, the computer  48  may be any Macbook® or iMac® model available from Apple Inc. It should be appreciated that the electronic device  10  may also take the form of any other computer, including a desktop computer. The computer  48  shown in  FIG. 4  includes the electronic display  18  and input structures  20  that include a keyboard and a track pad. Communication interfaces  16  of the computer  48  may include, for example, a universal serial bus (USB) connection. 
     In any case, as described above, operating an electronic device  10  to communicate information by displaying images on its electronic display  18  generally consumes electrical power. Additionally, as described above, electronic devices  10  often store a finite amount of electrical energy. Thus, to facilitate improving power consumption efficiency, an electronic device  10 , in some embodiments, may include an electronic display  18  that implements memory-in-pixel as a way to reduce, or eliminate, use of an external frame buffer in displaying images, and thus reduces power consumed by use of the frame buffer in displaying images and/or reducing a bandwidth of image data being received into the electronic display  18 . In some cases, an internal framebuffer (e.g., located in the electronic display  18 , such as in a display driver integrated circuit of the electronic display  18 ) may be used in lieu of or in addition to memory-in-pixel techniques. By implementing memory-in-pixel or related techniques, an electronic display  18  may be programmed with smaller bandwidths of image data, further enabling power consumption savings. In addition, an electronic display  18  using memory in the pixel or in an onboard frame buffer may have a less complex design than an electronic display  18  without memory in the pixel or without an onboard framebuffer. These benefits may be realized because a pixel retains data transmitted to its memory until new image data is written to the memory. 
     Similarly, portions of image data may program a subset of pixels associated with the electronic display  18  at a time. An image to be displayed is typically converted into numerical data, or image data, so that the image is interpretable by components of the electronic display  18 . In this way, image data itself may be divided into small “pixel” portions, each of which may correspond to a pixel portion of the electronic display  18 , or of a display panel corresponding to the electronical display  18 . In some embodiments, image data is represented through combinations of red-green-blue light such that one pixel appearing to have a single color is really three sub-pixels respectively emitting a proportion of red, green, and blue light to create the single color. In this way, numerical values, or image data, that quantify the combinations of red-green-blue light may correspond to a digital luminance level, or a gray level, that associates a luminance intensity (e.g., a brightness) of a color of the image data for those particular sub-pixels. As will be appreciated, the number of gray levels in an image usually depends on a number of bits used to represent the gray levels in a particular electronic display  18 , which may be expressed as 2 N  gray levels where N corresponds to the number of bits used to represent the gray levels. By way of example, in an embodiment where an electronic display  18  uses 8 bits to represent gray levels, the gray level ranges from 0, for black or no light, to 255, for maximum light and/or full light, for a total of 256 potential gray levels. Similarly, an electronic display  18  using 6 bits may use 64 gray levels to represent a luminance intensity for each sub-pixel. 
     Having memory in the pixels of an electronic display  18  enables image data to transmit to sub-pixels associated with one color without image data having to transmit to additional sub-pixels associated with a second color at the same time. For the purposes of this disclosure, sub-pixels are discussed in terms of red-green-blue color channels, where a color channel is a layer of image data including gray levels for a single color where when combined with additional color channels creates an image of a true, or desired, color, and where the image data for a color channel corresponds to image data transmitted to a sub-pixel for the color channel. However, it should be understood that any combination of color channels and/or sub-pixels may be used, such as, blue-green-red, cyan-magenta-yellow, and/or cyan-magenta-yellow-black. 
     To help illustrate, a display system  50  associated with an electronic display  18  that does not implement memory-in-pixel and a display system  52  associated with an electronic display  18  that does implement memory-in-pixel, which may each respectively be implemented in an electronic device  10 , is shown in  FIG. 5 . The display system  50  includes a timing controller  54  to receive image data  56 , a frame buffer  58 , a row driver  60  and a column driver  62  communicatively coupled through communicative link  64  to the timing controller  54 , and a pixel array  66  that receives control signals from the column driver  62  and the row driver  60  to create an image on an electronic display  18 . Furthermore, the display system  52  includes a timing controller  54  to receive image data  56 , a row driver  60  and a column driver  62  communicatively coupled through a communicative link  68  to the timing controller  54 , and a pixel array  69  implementing memory-in-pixel techniques that receives control signals from the column driver  62  and the row driver  60  to create an image on an electronic display  18 . 
     In preparing to display an image, the display system  50  may receive the image data  56  at the timing controller  54 . The timing controller  54  may receive and use the image data  56  to determine clock signals and/or control signals to control a provision of the image data  56  to the pixel array  66  through the column driver  62  and the row driver  60 . Additionally or alternatively, in some embodiments, the image data  56  is received by the frame buffer  58 . 
     In either case, the frame buffer  58  may serve as external storage for the timing controller  54  to store the image data  56  prior to output to the column driver  62  and/or the row driver  60 . The timing controller  54  may transmit the image data  56  from the frame buffer  58  to the column driver  62  and/or the row driver  60  through the communicative link  64 . 
     The communicative link  64  is large enough (e.g., determined through transmission bandwidth of image data) to simultaneously transmit image data  56  associated with all the channels to the row driver  60  and/or the column driver  62 , for example, the image data  56  associated with a red channel, a green channel, and a blue channel. In this way, the communicative link  64  communicates image data  56  associated with a respective pixel of the pixel array  66  for the red channel, the green channel, and the blue channel at the same time. The column driver  62  and the row driver  60  may transmit control signals based on the image data  56  to the pixel array  66 . In response to the control signals, the pixel array  66  emits light at varying luminosities, or brightness indicated through gray levels ranging from, for example, 0 to 255, to communicate an image. 
     However, the display system  52  receives the image data  56  at the timing controller  54 . The timing controller  54  may use the image data  56  to determine clock signals used to provision the image data  56  to the memory-in-pixel pixel array  69 . The timing controller  54  transmits the image data  56  to the row driver  60  and/or the column driver  62  to program the memory of the pixel array  69  with digital data signals associated with the image data  56 , where the digital data signals indicate the emission brightness/gray level for the pixels of the pixel array  69 . 
     By implementing memory-in-pixel systems and methods, the display system  52  may reduce a bandwidth of signals communicated over communicative link  68 , for example, when compared to a bandwidth of signals communicated over the communicative link  64 . In some instances, a single channel of image data  56  may transmit through the communicative link  64  (e.g., red channel), as opposed to all channels being simultaneously transmitted to the pixel array  66  (e.g., red-green-blue channels). In this way, the communicative link  68  communicates image data  56  associated with a respective pixel of the pixel array  66  for the red channel, the green channel, and the blue channel at different times, causing a decrease in an overall bandwidth of signals used to communicate image data  56 . Decreasing an overall bandwidth of the communicative link  68  may lead to a decrease in power consumption of the electronic device  10  because processing less data (e.g., a single channel of image data) at a given time may consume fewer processing resources than processing more data (e.g., three channels of image data). 
     To elaborate on operating the pixel array  69  with memory-in-pixel to display images, an example of a display system  52 A implementing memory-in-pixel having a timing controller  54  linked through communicative link  68  to a row driver  60  and/or a column driver  62 , is shown in  FIG. 6 . The display system  52 A includes a pixel array  69  of L rows by M columns with one or more pixels  70  each having sub-pixels  72  corresponding to color channels of the electronic display  18 , for example, a red sub-pixel  72 R, a green sub-pixel  72 G, and a blue sub-pixel  72 B, where each of the sub-pixels  72  includes a memory  78  to store up to N bits and a driver (DRV)  80  to operate the sub-pixel  72  to emit light, is shown in  FIG. 6 . It should be appreciated that the depicted display system  52 A is merely intended to be illustrative and not limiting. For example, in some embodiments, the pixel array  69  may include sub-pixels  72  to emit various amounts of cyan, yellow, and magenta light corresponding to cyan-yellow-magenta color channels instead of, or in addition to, the red-green-blue color channels. 
     Explaining operation of the display system  52 A, the timing controller  54  receives image data  56  corresponding to a next image to be displayed on an electronic display having the pixel array  69 . The timing controller  54  generates control signals and/or clocking signals responsive to the image data  56  and transmits signals related to operating rows of pixels  70  to the row driver  60  and transmits signals related to operating columns of pixels  70  to column driver  62 . The row driver  60  is responsive to the signals associated with the image data  56  transmitted from the timing controller  54  and generates emit control signals  82  and write control signals  84  for each red-green-blue (RGB) channel. The column driver  62 , also being responsive to the signals associated with the image data  56  transmitted from the timing controller  54 , generates image data  86  to be transmitted to the memory  78  of each of the pixels  70 . The column driver  62  may generate image data  86  in response to the signals associated with the image data  56  and/or the image data  56 , in some embodiments, however, image data  56  transmits to each of the pixels  70  as image data  86 . The column driver  62  generates data of size N bits for each sub-pixel  72 , matching a size of the memory  78  which is also size N bits. 
     Generally, through transmission of the emit control signals  82 , the write control signals  84 , and the image data  86 , the pixels  70  are operated to emit light to create an image on an electronic display  18 . Each of the pixels  70  receives a respective emit control signal  88  of the emit control signals  82  transmitted from the row driver  60 , a respective three write control signals  90  of the write control signals  84 , and respective image data  92  for the channels of the pixel  70 , for example, N bits of image data for the red channel (image data—R)  92 R, N bits of image data for the green channel (image data—G)  92 G, and N bits of image data for the blue channel (image data—B)  92 B. The write control signals  84  may enable a memory  78  of the pixel  70  to be programmed by the image data  86  transmitted by the column driver  62 . In addition, a respective emit control signal  88  of the emit control signals  82  may control if the pixel  70  is able to emit light. The emit control signal  88  transmits to respective pixels  70  of a column. An enabled emit control signal  88  may activate a driver  80  causing digital image data  92  from a memory  78  to transmit to a light-emitting portion of the pixel  70 , for example, a light-emitting diode associated (LED) with a sub-pixel  72 , that uses analog data signals to cause light emitted from the pixel  70 . In the depicted embodiment, columns of pixels  70 , for example, pixels  70  R1C1, R2C1, R3C1, to RLC1 in a first column receive a same emit control signal  88 . Image data  92  transmitted to a pixel  70  causes the pixel  70  to emit light of an overall color and/or brightness. 
     A perceived color emitted from the pixel  70  changes based on the light emitted from each of the three channels of the pixel  70 , that is, the light emitted from each respective sub-pixel. For example, operating each sub-pixel to output a brightness of 0, causes the pixel  70  to appear to be off while operating a red sub-pixel  72 R to output a brightness of 100%, a green sub-pixel  72 G to output a brightness of 50%, and a blue sub-pixel  72 B to output a brightness of 0% may cause a pixel  70  to emit an overall color that is perceived as an orange color. Thus, data is rendered and transmitted to each sub-pixel  72  to correspond to individual color channels of a pixel  70 . 
     Implementing memory  78  in a pixel  70  enables image data  92  to be programmed into the pixel  70  prior to a desired presentation time of the image. In some embodiments, an enabled write control signal  90  causes the memory  78  to clear (or overwrite) stored image data  92 , where not enabling a write control signal  90  may cause the memory  78  to retain the programmed image data  92 . For example, to write new image data, a write control signal—R  90 R may cause a memory  78  of a red sub-pixel  72 R to clear, enabling the writing of new image data, image data—R  92 R to be loaded into the memory  78 . In this example, a write control signal—B  90 B was not enabled, thus the memory  78  of the blue sub-pixel  72 B does not clear and continues to retain its programmed image data, image data—B  92 B. Having memory  78  in pixels  70  is an improvement to display technologies and processing technologies because memory  78  enables portions of image data  86  to be written at a time instead of a whole frame of data, causing improved use of available bandwidth to communicate image data for display on an electronic display  18 , as well as improvements to power consumption used for processing image data, as explained earlier with reference to  FIG. 5 . 
     In the pixel array  69 , image data  86  is communicated from the column driver  62  to the sub-pixels  72  through a direct communicative coupling, for example, through a communicative coupling  94 . In some embodiments, a multiplexing circuit may be used to control transmission of image data  86  to sub-pixels  72  such that a multiplexing control signal is used by the column driver  62  to arbitrate transmission of image data  98  to a sub-pixel  72 , for example, where in such arbitration a red sub-pixel  72 R may not receive image data  98  at the same time as a blue sub-pixel  72 B or a green sub-pixel  72 G. 
     To elaborate, an example embodiment of a display system  52 B associated with an electronic display  18  implementing memory-in-pixel including a timing controller  54  linked through communicative link  68  to a row driver  60  and a column driver  62 , is shown in  FIG. 7 . The display system  52 B, similar to the display system  52 A depicted in  FIG. 6 , includes a pixel array  69  of L rows by M columns with one or more pixels  70  each having sub-pixels  72 , for example, a red sub-pixel  72 R, a green sub-pixel  72 G, and a blue sub-pixel  72 B, where each of the sub-pixels  72  includes a memory  78  to store up to N bits and a driver (DRV)  80  to operate the sub-pixel  72  to emit light, is shown in  FIG. 6 . It should be appreciated that the depicted display system  52 B is merely intended to be illustrative and not limiting. It is noted functions and/or descriptions of the display system  52  that are common to both  FIG. 6  and  FIG. 7  are relied upon herein. 
     In the example embodiment of the display system  52 B in  FIG. 7 , the pixel array  69  includes a multiplexing circuit  96  that receives image data  98  of size N bits from the column driver  62 . The multiplexing circuit  96  is responsive to a respective multiplexing control signal (MUX control signal)  100  of multiplexing control signals  101 . The MUX control signal  100  may cause the multiplexing circuit  96  to output data to a sub-pixel  72  of a pixel  70 . In this way, the column driver  62 , through emission of the MUX control signal  100 , may operate to program a sub-pixel  72  (e.g., one color channel) of a pixel  70  at a time via, for example, a communicative coupling  94 . For the pixel array  69 , various embodiments of sub-pixel  72  circuits may be used. 
     An example of an embodiment of a sub-pixel  72  implementing memory-in-pixel techniques includes a memory  78 , a driver  80 , a current source  102 , a LED  103 , a switch  104 , and a counter  105 , where the sub-pixel  72  receives a variety of signals including image data  98 , a bit-plane clock  106 , a reset signal  108 , a common voltage  110 , a first reference voltage  112 , a second reference voltage  114 , and a data clock  116 , is shown in  FIG. 8 . It should be appreciated that the depicted sub-pixel  72  is merely intended to be illustrative and not limiting. For example, memory  78  is depicted as a 12-bit register but may be any suitable memory circuit to store any suitable number of bits. 
     The depicted sub-pixel  72  may emit according to a binary pulse width modulation emission scheme. To explain operation of the sub-pixel  72 , image data  98  transmits to the memory  78  from, for example, a column driver  62 . Additionally or alternatively, image data  92 , image data  56 , or any suitable image data may be transmitted to the memory  78  for storage. Upon receiving the image data  98 , the memory  78  stores the image data  98  clocked in by the data clock  116 . The image data  98  may be represented by binary data such that any given bit may equal a zero, “0,” or a one, “1”, where a 0 corresponds to a logical low voltage value for the system and a 1 corresponds to a logical high voltage value for the system. The memory  78  may output the image data  98  to the switch  104 , for example, bit by bit in order from least significant bit to most significant bit, according to a clocking signal generated by a combination of the counter  105  and the bit-plane clock  106 . 
     As shown, a bit-plane clock  106  has clocking time periods that increase over time to correspond to a level of influence of a particular bit in the image data  98 . In this way, a least significant bit of the image data  98  may be associated with a smaller clocking time period than a most significant bit of the image data  98 . 
     When the memory  78  outputs the image data  98 , for example, at a rising edge of the bit-plane clock  106 , the image data  98  operates the switch  104  to open or close. A 0 bit causes the switch  104  to open, causing the LED  103  to not emit light while a 1 bit causes the switch  104  to close, causing the LED  103  to emit light. The operation of the switch  104  occurs at varying emission periods as a method to modulate emission of light from the LED  103 , causing the perceived brightness of the sub-pixel  72  to change as the modulation changes. Thus, through the relationship between the image data  98  output from memory  78  and the switch  104 , image data  98  equaling “000000000000” may cause the LED  103  to not emit light while image data  98  equaling “101011000111” may cause the LED  103  to be perceived as brighter. The image data  98  equaling “101011000111” may be perceived as brighter because the sub-pixel  72  operates to emit light in response to each logical high value, “1,” through the value causing the switch  104  to activate permitting light to emit. The more times the switch  104  activates during an emission period, the brighter a pixel is perceived because the more light is emitted over time (e.g., light emits in response to the “1” and does not emit in response to the “0”). In this way, image data  98  may be derived from a desired gray level for the sub-pixel  72  without being an exact binary representation of the gray level. However, it should be noted that there may be scenarios where the desired gray level for the sub-pixel  72  does indeed equal the binary representation transmitted via image data  98 . 
     When the switch  104  closes, an electrical connection is created between the common voltage  110  and the first reference voltage  112 . This causes current from current source  102  to transmit through the LED  103  enabling light to emit from the sub-pixel  72 . Thus, emission periods of the sub-pixel  72  may be varied to control a perceived light emitted from the sub-pixel  72 , where the emission periods correspond to a bit placement (e.g., most significant bit, least significant bit) of the image data  98  stored in the memory  78  such that the closer a bit of image data  98  is to the most significant bit position, the longer an emission period corresponding to that bit of image data  98 . Once the counter  105  counts up to 11, the counter  105  restarts and causes the bit-plane clock  106  to restart its clocking intervals, for example, to correspond to a next least significant bit after the last most significant bit emission period. Additionally or alternatively, in some embodiments, the second reference voltage  114  is included to alter an overall current value used to control light emitted from the LED  103 . For instance, the second reference voltage  114  may increase a sensitivity of the LED  103  to current changes such that a lower current value may be used to cause light to emit from the LED  103 , or used to enable the LED  103 . 
     This emission scheme is generally referred to as a binary pulse width modulation emission scheme for a sub-pixel  72  because the image data  98  is binary data selected to modulate light emission from the sub-pixel  72  in such a way as to change a perceived brightness of the sub-pixel  72 . Graph  118  depicts emission periods for a sub-pixel  72  caused by the binary pulse width modulation emission scheme. With the binary pulse width modulation emission scheme, the sub-pixel  72  is operated to change a perceived brightness of light emitted through varying emission periods of light. As depicted in the graph  118 , image data  98  received by the sub-pixel  72  is represented through five bits of binary data. Thus, when the image data  98  equals 01111, the sub-pixel  72  emits light corresponds to a first range  120  having emission periods  124 A for the least significant bit and emission periods  124 B,  124 C, and  124 D for subsequent bits. In this embodiment, the least significant bit of the image data  98  from memory  78  operates the switch  104  first, hence why the least significant bit corresponds to a first emission period  124 A in time. As such, in between transmission of bits to operate switch  104 , emission temporarily halts, as is seen with the no emission period between the first emission period  124 A and the emission period  124 B. In addition, when the image data  98  equals 11111, the emission period of the sub-pixel  72  corresponds to a second range  122  that is equal to the first range  120  plus a last emission period  124 E corresponding to the most significant bit (e.g., because the most significant bit is now enabled as a 1). 
     When following a binary pulse width modulation emission scheme, image data  98  having data of 01111 is perceived as less bright than image data  98  having data of 11111 due to how light is perceived by a viewer of the electronic display  18 . This is because the more emission periods that occur during a total emission cycle (e.g., as represented by all is in the image data  98 , 11111), the brighter a light emitted from a sub-pixel  72  is perceived. As such, if the sub-pixel  72  were to emit for the last emission period  124 E in addition to the first range  120  (e.g., if the most significant bit of the image data  98  was a 1), the sub-pixel  72  may be perceived as brighter on an electronic display  18  than a sub-pixel  72  emitting just for the first range  120 . 
     Another example of an embodiment of a sub-pixel  72  including a memory  78 , a driver  80 , a current source  102 , a LED  103 , a switch  104 , a counter  130 , and a comparator  132 , where the sub-pixel  72  receives a variety of signals including image data  98 , a gray level clock  134 , a common voltage  110 , a first reference voltage  112 , a second reference voltage  114 , and a data clock  116 , is shown in  FIG. 9 . It should be appreciated that the depicted sub-pixel  72  is merely intended to be illustrative and not limiting. For example, memory  78  is depicted as an 8-bit register but may be any suitable memory circuit to store any suitable number of bits. 
     The depicted sub-pixel  72 , having memory-in-pixel, may emit according to a single pulse width emission scheme. To explain operation of the sub-pixel  72 , image data  98  transmits to the memory  78 , for example, from a column driver  62 , for storage. Additionally or alternatively, image data  92 , image data  56 , or any suitable image data may be transmitted to the memory  78  for storage. In some embodiments, the image data  98  may be clocked into the memory  78  by the data clock  116 , for example, on a rising edge of the data clock  116 . The image data  98  communicated to the sub-pixel  72  may correspond to a desired gray level at which the sub-pixel  72  is to emit light. Using the image data  98  stored in the memory  78 , the comparator  132  determines if a current number represented by the counter  130  is less than or equal to the image data  98  in memory  78 . In other words, the counter  130  counts up to the number indicated by the image data  98  and in response to the number represented by the counter  130  meeting a condition, for example, being smaller than or equal to the number indicated by the image data  98 , the comparator  132  outputs a control signal to close the switch  104  when the condition is met. When the condition is not met, the comparator  132  does not output a control signal and opens the switch  104 . Additionally or alternatively, the comparator  132  may enable a deactivation control signal to cause the opening of the switch  104 . For instance, if the memory  78  stores a binary sequence of 10110101 corresponding to the number  181 , the comparator  132  will check if the counter  130  has counted to the number  181 , and upon the counter  130  exceeding the number  181 , the comparator  132  transmits a signal to open the switch  104  thus stopping emission. 
     When the switch  104  closes, an electrical connection is created between the common voltage  110  and the first reference voltage  112 . This causes current from current source  102  to transmit through the LED  103  causing light to emit from the sub-pixel  72 . Thus, emission periods of the sub-pixel  72  may be varied to control a perceived light emitted from the sub-pixel  72  through changing a number indicated by the image data  98 . Additionally or alternatively, in some embodiments, the second reference voltage  114  is included to alter an overall current value used to control light emitted from the LED  103 . For instance, the second reference voltage  114  may increase a sensitivity of the LED  103  to current changes such that a lower current value may be used to cause light to emit from the LED  103 , or used to enable the LED  103 . 
     The counter  130  counts from 0 to 255 and increments based on a gray level clock  134 , for example, a rising edge of the gray level clock  134 . Periods of the gray level clock  134  represent the time difference between increments of the gray level for an electronic display  18 , for example, a difference in emission between emitting a gray level of 100 and emitting a gray level of 101. In this way, the counter  130  counts up to the number represented by the image data  98  stored in memory  78  subsequently causing emission to occur for the time period corresponding to the desired gray level. The counter  130  may continue to count beyond the number represented by the image data  98  stored in memory  78  on to a maximum value, for example, 255, and may restart counting at a minimum value, for example, 0. Thus, in some embodiments, a counting range of the counter  130  may be defined through design of the counter  130 , for example, through a number of registers and/or logical components included in the counter  130 . By the time the counter  130  restarts counting at 0, additional image data  98  may be stored into memory  78  to begin comparison for a next emission period of a gray level associated with the additional image data  98 . 
     Through following this emission scheme, the sub-pixel  72  may follow a single pulse width modulation emission scheme. A representation of an emission of light from a sub-pixel  72  following a single pulse width modulation emission scheme is shown in graph  136 . The graph  136  includes an actual emission period  138  and a total emission period  140 . The total emission period  140  corresponds to a total length of emission represented by a maximum number transmitted as image data  98 , for example, 255, and may correspond to a maximum perceived brightness of light emitted from the sub-pixel  72 . The actual emission period  138  corresponds to a period of time a sub-pixel  72  emitted light for according to a number less than the maximum transmitted as the image data  98 , for example, from a counter  130 . A counter  130  increments from 0 to 255 taking the amount of time represented by the total emission period  140  while the comparator  132  enables light to emit for the amount of time represented by the actual emission period  138 . In this way, a sub-pixel  72  may emit light of varying perceived brightness. 
     Another example of an embodiment of a sub-pixel  72  including memory  78 , a driver  80 , a current source  102 , a LED  103 , a switch  104 , an accumulator  150 , and an adder  152 , where the sub-pixel  72  receives a variety of signals including an emission clock  154 , image data  98 , a common voltage  110 , a first reference voltage  112 , a second reference voltage  114 , and a data clock  116 , is shown in  FIG. 10 . It should be appreciated that the depicted sub-pixel  72  is merely intended to be illustrative and not limiting. For example, memory  78  is depicted as being able to store 8-bits of image data  98  but may be any suitable memory circuit to store any suitable number of bits. 
     The depicted sub-pixel  72 , having memory-in-pixel, may emit according to a pulse density modulation emission scheme. In a pulse density modulation emission scheme each pulse has a constant light emitted and a constant emission period but variable separating intervals between pulses—where a brighter light emitted from the sub-pixel  72  corresponds to a higher number of pulses during a same time period. To explain operation of the sub-pixel  72  for the pulse density modulation emission scheme, image data  98  transmits to the memory  78 , for example, from a column driver  62 , for storage. Additionally or alternatively, image data  92 , image data  56 , or any suitable image data may be transmitted to the memory  78  for storage. The image data  98  transmitted to the sub-pixel  72  is generated based at least on a desired gray level at which the sub-pixel  72  is to emit light. 
     Upon receiving the image data  98 , the memory  78  stores the image data  98  according to the data clock  116 , for example, loading bits of image data  98  bit by bit on each rising edge of the data clock  116 . The memory  78  outputs the image data  98  to be added to binary data stored in the accumulator  150 . While the accumulator  150  is shown as being an 8-bit accumulator, it should be understood that any suitable accumulator or register may be used to temporarily store data. The adder  152  may perform binary addition of the image data  98  and binary data of the accumulator  150  in response to an emission clock  154 , for example, a rising edge of the emission clock  154 . The sum from the adder  152  is transmitted for storage in the accumulator  150  for use with next image data  98  while a carry bit is used to open and/or close the switch  104 . 
     When the switch  104  closes, an electrical connection is created between the common voltage  110  and the first reference voltage  112 . This causes current from current source  102  to transmit through the LED  103  generally enabling light to emit from the sub-pixel  72 . In this way, variable separating intervals between pulses created by the emission clock  154  and the adder  152  transmitting the carry bit from the addition may contribute to change emission of light from the sub-pixel  72 . Thus, intervals separating emission pulses of the sub-pixel  72  may be varied to control light emitted from the sub-pixel  72 , where a brighter light may emit in response to smaller intervals separating the pulses (e.g., a higher density of pulses corresponds to a brighter perceived light emitted from LED  103 ). Additionally or alternatively, in some embodiments, the second reference voltage  114  is included to alter an overall current value used to control light emitted from the LED  103 . For instance, the second reference voltage  114  may increase a sensitivity of the LED  103  to current changes such that a lower current value may be used to cause light to emit from the LED  103 , or used to enable the LED  103 . 
     Graph  156  depicts emission pulses and variable separating intervals between pulses caused by the pulse density modulation emission scheme. With the pulse density modulation emission scheme, the sub-pixel  72  emits pulses separated by different length of no emission intervals to change an overall light emitted from the sub-pixel  72 . As depicted in graph  156 , image data  98  may cause the sub-pixel to emit an emission pulse  158  and to not emit for the time period of a no-emission interval  160 . For example, emission pulses  162  have a smaller no-emission interval separating respective emission pulses than the emission interval  160 , and thus the LED  103  of the sub-pixel  72  may emit light for the emission pulses  162  that is perceived as brighter than a light emitted from the LED  103  due to the emission pulse  158 . 
     Thus, to summarize, through using memory-in-pixels techniques, a timing controller  54  may program image data  98  into a display system  52  in smaller portions of image data  98  as opposed to programming image data for all sub-pixels  72  at a same time. To illustrate, a timing diagram of signal transmitted within a display system  52  to prepare to transmit image data for storage in one or more memories  78  illustrates a red image data transmission period  174 R, green image data transmission period  174 G, blue image data transmission period  174 B, one or more copy periods  176 , and one or more enable periods  178 , is shown in  FIG. 11 . 
     As depicted, a column driver  62  may receive a signal to initiate the copying of red data into one or more memories  78  of one or more red sub-pixels  72 R. Upon receiving the signal, the column driver  62  may enter a copy period  176  to prepare for transmitting red data to the red sub-pixels  72 R. During the copy period  176 , the column driver  62 , for example, via internal circuitry such as a row decoder, may prepare to enable multiplexing circuits  96  associated with pixels  70  of a display system  52 . The column driver  62 , or other suitable circuitry, may operate the multiplexing circuits  96  to permit the programming of memories  78  of red sub-pixels  72 R and may operate the multiplexing circuits  96  to not permit the programming of memories  78  of blue sub-pixels  72 B and green sub-pixels  72 G, for example, through enabling and/or disabling multiplexing control signals  101 . In this way, the red image data may be transmitted and stored in the memories  78  corresponding to red sub-pixels  72 R. At the end of the copy period  176 , the column driver  62  may transmit red image data to the red sub-pixels  72 R during the red image data transmission period  174 R. The transmitted red image data is transmitted into the respective memories  78  of the red sub-pixels  72 R to be programmed with new red image data. Upon transmitting the red image data to the red sub-pixels  72 R, the column driver  62  and the row decoder may repeat the described process for green image data and blue image data, enabling selective programming of the various color channels associated with each pixel  70 . 
     Generally, a sub-pixel  72  is operated to emit light through receiving one or more control signals, such as, from the column driver  62  and/or the row driver  60 . The row driver  60  and the column driver  62  may control operation of the sub-pixel  72  by using control signals to control components of the sub-pixel  72 , such as a current drive of the sub-pixel  72 . As described above, the column driver  62  may be responsible at least for the transmission of image data to the sub-pixel  72  while the row driver  60  may be responsible for one or more control signals to control emission that transmit to the sub-pixel  72 . The sub-pixel  72  may include any suitable controllable element responsive to these control signals and image data, such as a transistor, one example of which is a metal-oxide-semiconductor field-effect transistor (MOSFET). However, any other suitable type of controllable elements, including thin film transistors (TFTs), p-type and/or n-type MOSFETs, and other transistor types, may also be used. 
     In some embodiments, the row driver  60  and/or column driver  62  may perform an initialization process, a charging process, a programming process, and an emission process to the sub-pixel  72  to prepare to display an image on an electronic display  18 . Through performing these processes, a row driver  60  and/or a column driver  62  of the electronic display  18  may initialize the sub-pixel  72  to be programmed, may charge a capacitor for programming, may program the sub-pixel  72  with signals corresponding to a driving current designed to cause the sub-pixel  72  to emit light, and may enable image data to control emission of light from the sub-pixel  72 . In some embodiments, a current drive may be responsible for generating the driving current in the sub-pixel  72 . 
     To help elaborate on a sub-pixel circuit having a current drive, an embodiment of a sub-pixel  72  including an initialization transistor (MINI)  220 , a driving transistor (MDR)  222 , a selection transistor (MSEL)  224 , a switching transistor (MS)  226 , a reset transistor (MRST)  228 , a light-emitting portion such as a LED  230 , a capacitor  232 , and an auto-zero transistor (MAZ)  234  is shown in  FIG. 12 . It should be appreciated that the depicted sub-pixel  72  is intended to be illustrative and not limiting. For example, the row driver  60  and the column driver  62  are described herein as outputting image data and control signals relevant to displaying a next image on an electronic display  18 , however it should be understood that any suitable component may be used to emit control signals to perform described processes to display of the next image. Furthermore, the circuitry shown in  FIG. 12  is merely an example of circuitry implemented in a sub-pixel  72  and/or a pixel  70 , and should not be interpreted as limiting. For example, a voltage drive circuit (e.g., voltage drive) may be used with the sub-pixel  72  instead of a current drive circuit (e.g., current drive). 
     During an initialization process, a row driver  60  may enable a reset control (CSreset) signal  235  and disable an auto-zero control (CSauto.zero) signal  237 . The CSreset signal  235  may transmit to the MRST  228 . In response to receiving the CSreset signal  235 , the MRST  228  may activate and permit the draining of residual signals from the display of the first image from the sub-pixel  72 . These residual signals may drain through to a node coupled to a voltage reset (Vreset) signal  239  designed to encourage draining of the residual signals (e.g., 0 volts), such as a system ground or a system reference voltage. In addition, the row driver  60  may enable a selection control (CSselect) signal  241 . The CSselect signal  241  may transmit to the MSEL  224 . In response to receiving the CSselect signal  241 , the MSEL  224  may activate and permit transmission of voltage data (Vdata) signal  242  to a node of the capacitor  232 . To complete the initialization process, the row driver  60  may also enable an initialization control (CSinitialization) signal  243 . The CSinitialization signal  243  may transmit to the MINI  220 . In response to receiving the CSinitialization signal  243 , the MINI  220  may activate and permit initialization of the capacitor  232  to occur. In this state, the capacitor  232  may charge with a voltage corresponding to a voltage difference between the Vdata signal  242  and an initialization voltage (Vinitialization) signal  244 . As such, the voltage difference may be programmed through selecting different values for Vdata signal  242  and Vinitialization signal  244  based on a desired voltage level to initialize the capacitor  232  with, while protecting the sub-pixel  72  from receiving additional signals that may interfere with the initialization or that may cause unintentional emissions of light from the LED  230 . The row driver  60  may continue the initialization process until the row driver  60  disabled the CSinitialization signal  243  causing the MINI  220  to deactivate. 
     After the initialization process, the row driver  60  may perform the charging process while the MINI  220  and the MRST  228  are deactivated. During the charging process, the MAZ  234  and the MINI  220  remain deactivated, while the MSEL  224  remains activated. While the MSEL  224  is activated, the capacitor  232  charges based on the Vdata signal  242  and a reference voltage (Vreference) signal  246 . Charging the capacitor  232  may enable a driving current to transmit through the MDR  222  even while the MSEL  224  is deactivated. In some embodiment, the capacitor  232  stores the voltage value of the Vdata signal  242  such that the MDR  222  remains activated throughout the emission process—permitting the sub-pixel  72  to produce a constant driving current through the LED  230  for emission. In this way, the sub-pixel  72  has a current drive—since the driving current enables the emission of light from the LED  230  while the MS  226  is activated. 
     During the programming process, the row driver  60  may enable the CSauto.zero signal  237  causing the activation of the MAZ  234 . When the MAZ  234  activates, an electrical coupling is formed between the node of the capacitor  232  and a source node of the MS  226 , such that a voltage value of the source node of the MS  226  increases to equal the voltage value of a gate voltage (Vg)  245  of MDR  222 . After period of time sufficient for the voltage of source node of the MS  226  to increase to equal the voltage value of Vg  245 , the row driver  60  may disable the CSauto.zero signal  237  causing the MAZ  234  to deactivate. At this state, the sub-pixel  72  is programmed with electrical signals ready to transmit through to the LED  230  upon activation of the MS  226 . That is, at this state, the sub-pixel  72  is ready to transmit a driving current created through the programmed signals in response to CSimage.data signal  247  enabling the MS  226 . 
     Upon completion of the programming process, the row driver  60  may operate the sub-pixel  72  to perform the emission process. During the emission process, the sub-pixel  72  emits light according to image data control (CSimage.data) signal  247  transmitted to the MS  226 , for example, from the column driver  62 . The sub-pixel  72  may receive the CSimage.data signal  247  from any suitable component of an electronic device  10  that may create and/or generate image data for display via a sub-pixel  72 . The MS  226  activates in response to an enabled CSimage.data signal  247 , for example, a logical high bit of a voltage having sufficient value to switch the MS  226  (e.g., large enough to overcome the programmed voltage at the source node of the MS  226  and a threshold voltage of the MS  226 ). Upon activation of the MS  226 , the voltage stored at the source node of the MS  226  transmits as a driving current through the LED  230 . If the driving current exceeds a threshold voltage of the LED  230 , where the threshold voltage of an LED represents a voltage value at or above which light emits from the LED, thus the LED  230  may emit light based at least in part on a value of the driving current. 
     As will be appreciated, the CSimage.data signal  247  may be binary and/or digital data representative of image data used to operate the sub-pixel  72  to emit at a particular gray level to convey an image (e.g., the second image). As discussed earlier, the sub-pixel  72  may operate according to a variety of emission schemes, and as such, the CSimage.data signal  247  transmitted to the MS  226  may vary between embodiments. However, across the embodiments, the CSimage.data signal  247  is derived from an image to be displayed on the display. Furthermore, the enabling and/or disabling of the CSimage.data signal  247  at least in part causes the LED  230  to emit light or to not emit light, and thus enables the CSimage.data signal  247  to modulate the emission of light from the sub-pixel  72 . 
     Upon a completion of the emission process, the row driver  60  may disable the CSselect signal  241  and enable the CSreset signal  235 , causing the deactivation of the MSEL  224  and the activation of the MRST  228 . Upon the MSEL  224  deactivating, the sub-pixel  72  may no longer operate to emit light because the capacitor  232  is no longer receiving a charge and because residual signals from the emission process are drained permitted by the enabling of the MRST  228 . 
     The sub-pixel  72  described is considered a current drive pixel because the sub-pixel  72  has a primary current that drives the LED  230  to emit light or not emit light. The primary, or driving, current transmits through MS  226  in response to various control signals controlling the timing of the light emission from the sub-pixel  72 . The described sub-pixel  72  circuit may have particular advantages including how a digital output is able to control emission from the LED  230  without further conversion into an analog output. In addition, inclusion of a capacitor  232  may enable compensation for a change of threshold voltage associated with the sub-pixel  72  from a substrate bias effect, a side effect associated with applying a voltage to a gate of some transistors. 
     Further improvements to the sub-pixel  72  may occur if a voltage drive is included in addition to the current drive structure of sub-pixel  72  in  FIG. 12 . At the beginning of the emission process, the voltage drive is enabled for a period of time to provide a boost to the anode of the LED  230  to make initial emission of light easier, where a lower driving current may be used to enable light emission than without boosting the anode of the LED  230 . A smaller driving current value may be used to drive the LED  230  to emit light because the LED  230  may operate in a forward bias region, or an operating region of an LED  230  more sensitive to small changes in currents, because of the boost provided by the voltage drive. 
     To illustrate, a second embodiment of the sub-pixel  72  having a hybrid drive including a current drive  270  and a voltage drive  272  and having a memory  78  is shown in  FIG. 13 . It should be appreciated that the depicted sub-pixel  72  is intended to be illustrative and not limiting. For example, the current drive  270  and the voltage drive  272  are shown as separate elements in the sub-pixel  72  but one or both of the drives may be included in the driver  80  described earlier. 
     A row driver  60  and/or a column driver  62  may operate the sub-pixel  72  to emit light by enabling and/or disabling control signals. The row driver  60  and/or the column driver  62  may use the control signals to perform various processes to cause the sub-pixel  72  to emit light, including an initialization process, a charging process, a programming process, and an emission process for the sub-pixel  72  to enable display of the image data corresponding to an image to be displayed. 
     To help illustrate the interaction of control signals emitted by the row driver  60  and/or the column driver  62  and the sub-pixel  72  of  FIG. 13 , a timing diagram  279  corresponding to signals used to display including a Vdata signal  242 , a CSinitialization signal  243 , a CSselect signal  241 , a CSauto.zero signal  237 , an CSimage.data signal  247 , a CSselect signal  280 , and a CSreset signal  235 , is shown in  FIG. 14 . It should be appreciated that the timing diagram is intended to be illustrative and not limiting, for example, control signals shown in  FIG. 14  may represent more or less control signals than implemented in a sub-pixel  72 . 
     The initialization process described above corresponds to a time period  282 . During the time period  282 , a row driver  60  may provide a high voltage for the Vdata signal  242 , may enable the CSinitialization signal  243  for the duration of the initialization process, may enable the CSselect signal  241  for a time period  284 , may disable the CSauto.zero signal  237 , may disable the CSreset signal  235 , and may disable the CSselect signal  280 . 
     Referring back to  FIG. 13 , the control signals outputted by the row driver  60  to execute an initialization process cause activation and/or deactivation of various switching elements, as described earlier. Implementing the control signals of  FIG. 14  into the sub-pixel  72  causes a MINI  220  to activate in response to the enabled CSinitialization signal  243 , causes a MSEL  224  to activate in response to the enabled CSselect signal  241 , causes a MAZ  234  to deactivate in response to the disabled CSauto.zero signal  237 , causes a MRST  228  to deactivate in response to the disabled CSreset signal  235 , and causes a voltage drive switching element (MVD)  285  to deactivate in response to the disabled CSselect signal  280 . This arrangement enables a difference in voltage values between the Vdata signal  242  and the Vinitialization signal  244  to charge a capacitor  232 . The row driver  60  may continue the initialization process until the row driver  60  disables the CSinitialization signal  243  to cause the MINI  220  to deactivate, and thus end initialization. 
     Referring back to  FIG. 14 , the timing diagram  279  shows, after the initialization process, the row driver  60  disables the CSinitialization signal  243  to perform a charging process to the sub-pixel  72 . During the charging process, the Vdata signal  242 , the CSauto.zero signal  237 , the CSimage.data signal  247 , the CSselect signal  280 , and the CSreset signal  235  remain at their previous state. The timing diagram  279  shows the Vdata signal  242  at a high voltage level for the sub-pixel  72  circuit (DVDD), for example, corresponding to a logical high value in binary data for the sub-pixel  72  and/or the electronic device  10 . In some embodiments, DVDD is equal to a voltage value of the Vreference signal  246 . 
     Referring back to  FIG. 13 , the control signals outputted by the row driver  60  activate and/or deactivate various switching elements to execute a charging process. Upon the disabling of the CSinitialization signal  243  and the deactivation of the MINI  220 , the capacitor  232  charges based on the Vdata signal  242  and the Vreference signal  246 . Charging the capacitor  232  may enable the current drive  270  to remain in use during the emission process even while the MSEL  224  is deactivated. In some embodiments, the capacitor  232  holds the voltage value of the Vdata signal  242  after the charging process such that the MDR  222  may remain activated throughout the emission process—permitting the current drive  270  to produce a constant driving current through the LED  230  for emission. 
     After a set period of time suitable to charge the capacitor  232 , the row driver  60  may perform a programming process. Referring briefly to  FIG. 14 , to perform the programming process, the row driver  60  enables the CSauto.zero signal  237  for a time period  286  and holds CSinitialization signal  243 , the Vdata signal  242 , the CSimage.data signal  247 , the CSselect signal  280 , and the CSreset signal  235  at their previous state. As is shown, the row driver  60  also transmits a ground voltage (GND) as the Vdata signal  242  for a time period  288  during the programming process. The GND may equal zero volts or any suitable ground reference voltage associated with an electronic display  18 , an electronic device  10 , and/or a sub-pixel  72 . 
     Returning to  FIG. 13 , in response to the enabled CSauto.zero signal  237 , the MAZ  234  activates. When the MAZ  234  activates, an electrical coupling is formed between the node of the capacitor  232  and a source node of the MS  226 , such that a voltage value of the source node of the MS  226  increases to equal the voltage value of Vg  245 . After the time period  286 , the row driver  60  disables the CSauto.zero signal  237  and the MAZ  234  deactivates. At this state, the sub-pixel  72  is programmed with electrical signals ready to transmit to the LED  230  upon activation of the MS  226 . That is, at this state, the sub-pixel  72  is ready to transmit a driving current created through the programmed signals in response to CSimage.data signal  247  enabling the MS  226 . Once the source node of the MS  226  is programmed with the Vg  245  voltage, the row driver  60  transmits a Vdata signal  242  equal to GND and, at the end of the time period  284 , disables the CSselect signal  241  causing the MSEL  224  to deactivate. Upon the completion of the programming process, the row driver  60  may enable and/or disable control signals to perform an emission process. 
     Referring to  FIG. 14 , during an emission process, the row driver  60  may return a Vdata signal  242  to DVDD, may continue to disable the CSinitialization signal  243 , may continue to disable the CSselect signal  241 , may enable the CSimage.data signal  247  for a time period  290 , may enable the CSselect signal  280  for a time period  292 , and may continue to disable the CSreset signal  235 . As is illustrated, the CSselect signal  280  is enabled at the same time as the CSimage.data signal  247 , however is disabled earlier than the CSimage.data signal  247 . This is because the CSselect signal  280  acts to activate a switching element to provide the boost to an anode of an LED  230  of the sub-pixel  72 . 
     Returning to  FIG. 13  to illustrate, a voltage drive switching element (MVD)  285  of the sub-pixel  72  activates in response to the enabling of the CSselect signal  280  causing the voltage drive  272  to activate. In response to the MVD  285  activating, a reference voltage (Vreference) signal  300  transmits to the anode of the LED  230  upon the CSimage.data signal  247  enabling a switching transistor (MS)  302  and the MS  226  for a first transmitted CSimage.data signal  247 . This causes the Vreference signal  300  to transmit at the anode of the LED  230  enabling, or “boosting,” a smaller programmed value from the source of the MS  226  to cause emission of light from the LED  230 . The boosting may continue for the time period  292 , where upon the ending of the time period  292 , the row driver  60  disables the CSselect signal  280  causing the deactivating of the MVD  285  and of the MS  302 . 
     Generally, the emission process may continue for the time period  290  with the boost lasting for a shorter time period, for example, a time period  292 . During the emission process, the sub-pixel  72  is programmed to transmit the driving current through the LED  230  in response to the activation of the MS  226 . As described earlier, the memory  78  of the sub-pixel  72  stores digital data and outputs digital data. Through the described hybrid drive, stored digital data is transmitted from memory  78  as digital data turning into a control signal to control the emission of light from the sub-pixel  72  with little overhead and no increased consumption of power. At the conclusion of boosting, in some embodiments, the sub-pixel  72  may be reset via enabling of the CSreset signal  235 , for a duration such as time period  294 . Thus, light emitted from the LED  230  may follow a variety of emission schemes, as explained earlier with  FIG. 8 - FIG. 10 , to communicate gray levels associated with an image because the binary data outputted from the memory  78  acts to modulate the light emitted via the LED  230 . 
     To help illustrate effects of the “boost” to an anode voltage of a sub-pixel  72 , a graph  348  illustrating an example CSimage.data signal  350 , a voltage signal  352  corresponding to a voltage at an anode of a LED  230 , and a current signal  354  corresponding to a current through the LED  230  for a sub-pixel  72  not implementing a hybrid drive, is shown in  FIG. 15 . It should be appreciated that the timing diagram is intended to be illustrative and not limiting. 
     In this simulation, a binary pulse width modulation emission scheme was tested by providing an increasingly wider binary pulse as the CSimage.data signal  350 . The simulation results, shown in the graph  348 , generally has two portions. A first portion  356  may correspond to a slower emission response time and a second portion  358  may correspond to a normal emission response time, where an emission response time generally refers to a relative responsiveness of an LED  230  to voltages applied to it. It is also worth noting that an LED, like the LED  230 , operates to conduct based on the difference in voltages between an anode and a cathode of the LED. If the difference in voltage between the anode and the cathode is greater than a threshold voltage, the LED operates to emit light according to a value of the current transmitted through the LED. In the graph  348 , the current signal  354  may generally correspond to LED  230  emission, where the closer the current signal  354  values matches a state of the CSimage.data signal  350 , the better the emission response time of the LED  230 . In the graph  348 , the effects of a slow charge effect on the anode voltage of the LED  230  are clear. During the first portion  356 , the current signal  354  appears to be less responsive to state changes of the CSimage.data signal  350  than the second portion  358 , as indicated by the general matching of amplitudes of the current signal  354  and the CSimage.data signal  350  during the second portion  358  and the lack thereof during the first portion  356 . Boosting the anode at the beginning of an emission period may reduce, or eliminate, the slow charge effect of the anode voltage. 
     Proceeding onto  FIG. 16 , for comparison, a graph  370  illustrating an example CSimage.data signal  350 , a voltage signal  374  corresponding to a voltage at an anode of a LED  230 , and a current signal  376  corresponding to a current through the LED  230  for a sub-pixel  72  having a hybrid drive, is shown in  FIG. 16 . It should be appreciated that the timing diagram is intended to be illustrative and not limiting. For example, while the CSimage.data signal  350  is shown to follow binary pulse width modulation emission scheme, any suitable emission scheme may cause the same improvement to responsiveness as is described below. 
     In this simulation, similar to the graph  348 , a binary pulse width modulation emission scheme was tested by providing an increasingly wider binary pulse as the CSimage.data signal  350 . However, unlike the graph  348 , the graph  370  shows the current signal  376  to be responsive to changes in the CSimage.data signal  350 . This improved responsiveness is due at least in part to the addition of the voltage drive  272  to the sub-pixel  72 . Because the voltage drive  272  of the hybrid drive is “boosting” the anode of the LED  230 , smaller changes in voltages at the anode of the LED  230  may elicit the same and/or similar responsiveness of the second portion  358  of the graph  348 . Thus, the graph  370  shows the benefits and improvements to display technologies provided by at least implementing a hybrid drive in a sub-pixel  72 . 
     As described above, a display implementing memory-in-pixel techniques may implement a variety of pixel circuitry embodiments and a variety of memory circuitry embodiments to achieve benefits described earlier in this disclosure. An example embodiment is a memory circuit supporting a binary pulse width emission scheme, where digital data stored in the memory circuit is outputted to the driver circuit to control emission of light from a pixel. As a reminder, the binary pulse width emission scheme works in tandem with a clocking signal, for example, a bit-plane clock, to assign contribution weights to the different portions of digital data transmitted from the memory circuit. In some embodiments, the clocking signal is used to clock a register to output stored digital data from a memory circuit. However, in some embodiments, a system clock and/or a row driver  60  may control light emission duration through a length of time that an emission-enabling signal is enabled. 
     To help illustrate the memory circuit that facilitates in controlling emission via an emit-enable signal, a sub-pixel  72  including memory circuitry  400 A, analog driver circuitry  402 , and light-emitting circuitry  404  is shown in  FIG. 17 . It should be appreciated that the sub-pixel  72  is intended to be illustrative and not limiting. For example, while the memory circuitry  400 A is shown as storing twelve bits of digital data, any suitable memory circuit may be used, such as circuitry to store more than or less than twelve bits of digital data. 
     The memory circuitry  400 A may include write_enabling transistors (MWR)  406 , one or more inverter pairs  408 , and transmission selection transistors (MSEL)  410 . The memory circuitry  400 A receives and stores digital data (DATA)  412 , for example, from a column driver  62 . Prior to the memory circuitry  400 A storing the DATA  412 , a row driver  60  may enable a write_enabled control signal (write_en)  414  to activate the MWRs  406  to permit writing image data to memory (e.g., inverter pairs  408 ) so the memory may memorize the image data. Upon receiving the DATA  412 , the inverter pair  408  stores the DATA  412  value. It should be emphasized that using the memory circuitry  400 A permits parallel transmission of the DATA  412 , such that all bits of DATA  412  are stored in the respective inverter pairs  408  at the same time, or in the same write cycle (e.g., when the write_en signal  414  is enabled) in addition to bitwise transmission where each bit of DATA  412  is stored one bit at a time. The MSEL  410  activates in response to an enabled selection control signal (Sel)  415  transmitted by, for example, the row driver  60  which operates to activate the MSEL  410  of the bit of memory targeted to transmit to analog driver circuitry  402 . In this way, the MSEL  410 A may be activated at the same time that the MSEL  410 B is deactivated. Thus, the memory circuitry  400 A is loaded with one or more DATA  412  bits before an emission process begins, and the DATA  412  is read bit by bit facilitated by the activation of respective MSEL  410 . 
     At the beginning of an emission process, for example, the emission process as described in  FIG. 14 , the row driver  60  may enable a precharge control signal (Precharge)  416  as a way to initially enable light emission based at least in part on activation of an emission transistor (MEM)  419 . The MEM  419  may activate in response to the row driver  60  enabling of an emission control signal (Emit_en)  420 . In some embodiments, the row driver  60  may enable the Precharge signal  416  at the same time as the Emit_en signal  420  to permit the Vreference signal  246  to transmit to a MS  226  to precharge, or boost, the anode of the LED  230  prior to an activation of the MSEL  410 . After precharging completes and during the emission process, the Emit_en signal  420  may continue to be enabled by the row driver  60 . While row driver  60  disables the Precharge signal  416  after precharging to cause the stored DATA  412  to at least in part control activation of the MEM  419 . In this way, stored DATA  412  transmitting from the inverter pair  408  may cause the MEM  419  to activate in response to a logical value of the stored value (e.g., “1” or “0”). It is noted that in some embodiments, the logical high value is equal to the Vreference signal  246 , and the logical low value is equal to a Vreference signal  248 . 
     Upon the stored DATA  412  transmitting from the memory circuitry  400 A, the light-emitting circuitry  404  receives the stored DATA  412  at the gate of a MS  226 . The MS  226  activates in response to the stored DATA  412  value, enabling a current generated by the analog driver circuitry  402  to transmit through to the LED  230  to cause light emission. Emission may continue as long as the stored DATA  412  is applied as a CSimage.data signal  247 . In this way, light emits from the sub-pixel  72  following the initialization process, the charging process, the programming process, and the emission process generally described with  FIG. 12  through  FIG. 14 . 
     An additional embodiment of a sub-pixel  72  having memory circuitry  400 B and an analog driver circuitry  442  including light-emitting circuitry  404  is shown in  FIG. 18 . It should be appreciated that the sub-pixel  72  is intended to be illustrative and not limiting. For example, while the memory circuitry  400 B is shown as storing sixteen bits of digital data, any suitable memory may be used, such as circuitry to store more than or less than sixteen bits of digital data. In addition, while the sub-pixel  72  is depicted as having a LED  230  included in the light-emitting circuitry  404 , any suitable light-emitting circuitry  404  may be combined with described memory-in-pixel techniques. 
     The memory circuitry  400 B is depicted as including one or more write enabling transistors (MWRs)  406 , one or more inverter pairs  408 , and one or more selection transistors (MSELs)  410 . DATA  412  is received into the memory circuitry  400 B from, for example, a column driver  62 . To transmit DATA  412  into the memory circuitry  400 B, a row driver  60  may enable a write_en signal  406  and an inverse of the write_en signal (inverse write_en)  444  to enable bitwise memory storage of the DATA  412 . For example, the row driver  60  may enable storage of a last bit of DATA  412  in the inverter pair  408 B by activating MWR  406 D and/or MWR  406 C. Thus, the row driver  60  and the column driver  62  may operate to enable bitwise transmission and storage of DATA  412  into the memory circuitry  400 B. 
     Upon storage of the DATA  412  in the inverter pairs  408 , the memory circuitry  400 B stores the DATA  412  value until the row driver  60  selects a respective bit for transmission. Prior to selecting the respective bit for transmission, the row driver  60  precharges the sense amplifier  440  via enabling of a precharge (Precharge) signal  416 . By precharging the sense amplifier  440  and subsequent analog driver circuitry  442 , the sub-pixel&#39;s  72  responsiveness to transmitted electrical signals may improve when compared to a sub-pixel  72  not precharged. As described prior, precharging a sub-pixel  72  may make switching states easier and less demanding on circuitry (e.g., by increasing circuitry responsiveness). 
     Upon completion of precharging, the row driver  60  selects a bit for transmission to the analog driver circuitry  442  to cause emission according to stored DATA  412 . To transmit a bit to the analog driver circuitry  442 , the row driver may enable a Sel signal  415  to activate MSEL  410  corresponding to an inverter pair  408 . For example, the row driver  60  may enable a Sel signal  415 A to activate MSEL  410 A and MSEL  410 B to cause transmission of DATA  412  stored in inverter pair  408 A to transmit to the analog driver circuitry  442 . 
     In some embodiments, DATA  412  transmits through a sense amplifier  440  before transmitting to the analog driver circuitry  442 . The sense amplifier  440  acts to sense a logical state of the DATA  412  and may amplify the sensed logical state into an interpretable logical state (e.g., by increasing signal amplitude) for adjoining circuitry. The interpretable logical state may be based at least in part on a threshold voltage of MS  226  of the analog driver circuitry  442 . For example, a bit transmitted to node  446  outputs as having a larger voltage value at node  448 , caused by transmission through the sense amplifier  440  and based at least in part on a voltage difference between a Vreference signal  248  and a Vreference signal  246  representing any suitable voltage value common to a display system (e.g., display system  52 ). 
     After DATA  412  is amplified, the amplified DATA  412  transmits to the analog driver circuitry  442  as a CSimage.data signal  247  to activate or deactivate the MS  226 . For example, in some embodiments, the MS  226  deactivates in response to transmitted logical high DATA  412  (e.g., transmitted as the CSimage.data signal  247 ) and activates in response to transmitted logical low DATA  412 . In this way, the voltage value of the digital data transmitted as the CSimage.data signal  247  corresponds to a bias voltage of the MS  226 , or a voltage value that operates the MS  226  to change state. Upon activation of the MS  226 , a driving current, generated by analog driver circuitry  442  based at least in part on a voltage difference between a Vreference signal  450  and a Vreference signal  451 , transmits through the LED  230  enabling the sub-pixel  72  to emit light. Thus, in the way described, DATA  412  stored in the memory circuitry  400 B may drive light emission from pixel circuitry (e.g., sub-pixels, pixels). 
     To summarize operation of the sub-pixel  72  embodiment of  FIG. 18  and of  FIG. 17 , an example of a process  461  for controlling operation of a sub-pixel  72  coupled to memory circuitry  400  is described in  FIG. 19 . Generally, the process  461  includes loading memory with a current bit (block  462 ), determining if the current bit is the last bit to be loaded into memory (block  464 ), in response to the current bit not being the last bit, loading the memory with a next current bit (block  462 ), and in response to the current bit being the last bit, enabling selection signal to permit reading of a bit from the memory (block  466 ), waiting for the bit to cause emission in pixel circuitry (block  468 ), and determining if the bit is a last bit to be read from memory (block  471 ). In response to the bit being the last bit, completing the display cycle (block  472 ) and in response to the bit not being the last bit, enabling a next selection signal to permit reading of a next bit from the memory (block  466 ). In some embodiments, the process  461  may be implemented at least in part by executing instructions stored in a tangible, non-transitory, computer-readable medium, such as one or more storage devices  14 , using processing circuitry, such as the processing core complex  12 . Additionally or alternatively, the process  461  may be implemented at least in part based on circuit connections formed in display controlling circuitry, such as a row driver  60 , a column driver  62 , and/or a timing controller  54 . 
     Thus, in some embodiments, a row driver  60  may load memory circuitry  400  with a current bit (block  462 ). As is described above, the row driver  60  selectively enables a respective switching element, such as MWR  406 B or MWR  406 D, to enable bitwise loading of the current bit of DATA  412  into the memory circuitry  400 . Upon the enabling of MWR  406 , a bit corresponding to a current bit of DATA  412  transmits for storage, such as, in an inverter pair  408  where the value of the current bit is continually inverted until the bit is selected for transmission. 
     After loading the current bit into memory, the row driver  60  may determine if the current bit is a last bit (block  464 ). The last bit represents a final bit of DATA  412  (e.g., a last bit to be stored in memory circuitry  400 ). Thus, checking if the current bit is the last bit checks if all of the DATA  412  has transmitted from a column driver  62  for storage. A variety of techniques may be implemented to determine if a current bit is a last bit including, for example, maintaining a separate count to track a current bit position with respect to a final bit position. 
     In response to the current bit not being the last bit, the row driver  60  may load the memory circuitry  400  with a next current bit (block  462 ). As described above, the row driver  60  enables a next respective switching element to enable bitwise transmission of a next bit of DATA  412  into memory circuitry  400  as the next current bit. Thus, the process  461  repeats until the last bit of DATA  412  is stored into the memory circuitry  400 . 
     However, in response to the current bit being the last bit, the row driver  60  may enable a selection signal to transmit a bit from the memory (block  466 ). When the current bit is the last bit, the row driver  60  determines the target data to store in the memory circuitry  400  has completed loading into memory—thus, at this point, the row driver  60  transmits the stored DATA  412  bit-by-bit, or bitwise, to the analog driver circuitry  442  to cause light emission from the sub-pixel  72  at a level, or luminosity, corresponding gray to the DATA  412 . In some embodiments, the row driver  60  transmits stored bits in an order from least significant bit to most significant bit, however any suitable order for the memory circuitry  400  and the display system  52  may be used. To cause transmission, the row driver  60  enables a Sel signal  415  corresponding to the target bit from the memory circuitry  400  for reading. Upon the enabling of the Sel signal  415 , the target bit transmits to the sense amplifier  440  and/or to the analog driver circuitry  442  to cause light emission. 
     Next, the row driver  60  may wait a programmed time period for the transmitted bit from memory to cause light to emit from the sub-pixel  72  (block  468 ). While the row driver  60  waits, the bit stored in the inverter pair  408  transmits to the MS  226 . Upon activation of the MS  226 , analog driver circuitry  442  permits a driving current to transmit through a LED  230  causing light emission from the sub-pixel  72 . As previously described with  FIG. 8 , a bit-plane clock  106  may act to modulate widths of light emission to correspond to a significance of the bit from memory to the overall perceived gray level. The row driver  60  may use the bit-plane clock  106  to modulate light emission from the sub-pixel  72 , for example, through modulating overall emission of the sub-pixel  72  (e.g., via enabling the Emit_en signal  420 ) and/or through modulating the time period that a bit is selected to transmit from the memory circuitry  400  (e.g., via enabling for a time period corresponding to significance of bit the Sel signal  415  to activate MSEL  410 ). It is noted that in some embodiments the row driver  60  does not wait and continues to determine if the bit read from the memory circuitry  400  was the last bit of the stored DATA  412 . 
     After reading the bit, the row driver  60  may determine if the bit the last bit of the stored DATA  412  (block  471 ). The row driver  60  determines if the last bit has been read and/or transmitted to analog driver circuitry  442 . A row driver  60  may mange this determination through a variety of ways, for example, maintaining a counter that increments in tandem with enabling of Sel signal  415  to indicate when the row driver  60  has read an expected number of bits from the memory circuitry  400 . 
     If the bit is the last bit, the row driver  60  may complete the display cycle (block  427 ). The display cycle may include the whole process  461  such that upon reaching block  427 , the row driver  60  has emitted the gray level of light corresponding to the DATA  412 . Upon completing the display cycle, the row driver  60  may be ready to accept new DATA  412  corresponding to a same or different gray level for emission. 
     However, in response to the bit not being the last bit, the row driver  60  may enable a next selection signal to permit reading of a next current bit from the memory (block  466 ). The row driver  60  may manage the enabling of the next selection signal in a variety of ways, for example, maintaining a separate count to track a current transmitted bit position with respect to a final transmitted bit position. In any case, the row driver  60  determines the Sel signal  415  to enable (e.g., the Sel signal  415  corresponding to the bit to be transmitted next from the memory circuitry  400 ). When the row driver  60  determines which Sel signal  415  to enable, the row driver  60  enables the Sel signal  415  causing activation of a MSEL  410  corresponding to a target bit for transmission. The row driver  60  may repeat transmitting bits of the stored DATA  412  until a last bit is reached. Upon reaching the last bit, the row driver  60  completes the emission cycle and may prepare for a next emission cycle (block  427 ). 
     For  FIG. 18  and  FIG. 19 , the sub-pixel  72  embodiments described have analog driver circuitry  442  with a global anode. An additional embodiment of a sub-pixel  72  may have analog driver circuitry  442  with a global cathode. 
     A sub-pixel having a global cathode including memory circuitry  400 C, analog driver circuitry  442  having light-emitting circuitry  404  is shown in  FIG. 20 . It should be appreciated that the sub-pixel  72  is intended to be illustrative and not limiting. For example, while the memory circuitry  400 C is shown as storing sixteen bits of digital data through bitwise transmission of data, any suitable memory circuit may be used, such as circuitry to store more than or less than sixteen bits of digital data and/or circuitry to permit parallel transmission of data. 
     In the depicted embodiment, the cathode of a LED  230  is coupled to a reference voltage (Vreference) signal  470  and the anode of the LED  230  is coupled to a reference voltage (Vreference) signal  473  through MS  226 A, MS  226 B, MS  276 , and MS  278 . As explained earlier, after DATA  412  is stored in the memory circuitry  400 C and, in some embodiments, after precharging circuitry via Precharge signals  416 , the row driver  60  may enable Emit_en signal  420  to cause light emission. Upon activation of MEM  480  and MEM  482 , a stored DATA  412  bit transmits through the sense amplifier  440  and the amplified bit transmits to the MEM  480  while an inverted version of the stored DATA  412  bit transmits to MEM  482  without amplification. The inverted bit and the amplified bit are used as control signals to activate the MS  226 A and  226 B, effectively acting like the CSimage.data signal  247  from previous discussions. Upon activation of the MS  226 A and MS  226 B, analog driver circuitry  442  generates a driving current based at least in part on the voltage difference between Vreference signal  473  and Vreference signal  470  to transmit through a LED  230  to cause light emission. 
     In a similar fashion as the global anode embodiment, the global cathode sub-pixel  72  may create different gray levels through following a binary pulse width modulation scheme. The binary pulse width modulation scheme may use a bit-plane clock in part to control the control signals outputted from the row driver  60 . In this way, the Emit_en signal  420  may be enabled for shorter time periods for bits of lesser significance (e.g., least significant bit of DATA  412 ) on the perceived gray level and may be enabled for longer time periods for bits of greater significance (e.g., most significant bit of DATA  412 ) on the perceived gray level. In some embodiments, a Sel signal  415  may be modulated to cause light to emit from the sub-pixel  72  according to different gray levels. 
     As described in  FIG. 9 , using memory-in-pixel techniques and a comparator may enable a row driver to create a single pulse width modulation emission scheme. Accordingly, an embodiment of a sub-pixel  72  including a comparator  490 , memory circuitry  491 , and memory circuitry  492  is shown in  FIG. 21 . It should be appreciated that the sub-pixel  72  is intended to be illustrative and not limiting. For example, while the memory circuitry  492  is shown as being coupled to LED driver circuitry and to light-emitting circuitry of the sub-pixel  72 , the memory circuitry  492  may couple to any suitable light-emitting circuitry and/or driving circuitry. 
     In the depicted sub-pixel  72 , DATA  412  of size n bits is received into the memory circuitry  491  following a similar process as described earlier, that is, a row driver  60  operates to enable a write_en signal  494  to cause transmission of DATA  412  into the inverter pairs  496 . In some embodiments, the row driver  60  operates in tandem with a column driver  62  to cause parallel transmission of all bits associated with DATA  412  into the inverter pairs  496  by enabling write_en signals  494  at the same time. Additionally or alternatively, the row driver  60  may cause bitwise transmission of bits associated with DATA  412  through selectively enabling write_en signals  494 , for example, loading a bit into inverter pair  496 A by selectively enabling write_en signal  494 A to cause transmission of the first bit of DATA  412 . 
     Once DATA  412  is stored in the inverter pairs  496 , the comparator  490  uses stored DATA  412  bits and bits transmitted from counting circuitry (e.g., counter  130 ) to perform a comparison between the two sets of bits. As a reminder, in the single pulse width modulation emission scheme, counting circuitry, like the counter  130 , increments up to a maximum gray level on the rising edge of a clocking signal, like a gray level clock  134 , where light emission occurs from the sub-pixel  72  until the counting circuitry counts up to a number equaling and/or exceeding a number represented by stored DATA  412 . In this way, the comparator  490  performs a compression of all of the bits of DATA  412  into a single bit indicative of if the DATA  412  is the same as the count transmitted from counting circuitry. Thus, the comparator  490  performs a bitwise XNOR compression to a single bit having an embodiment of memory circuitry  491  and memory circuitry  492 , where an output from the comparator  490  is a logical low (e.g., “0”) value unless every bit matches. If every bit matches, the comparator  490  outputs a logical high value. The output from the comparator  490  is stored in memory circuitry  492 , where the value is retained in the inverter pair  498  until the row driver  60  enables an emit_en signal  420  to cause emission of the stored comparator  490  output to the LED driver and light-emitting circuitry to drive light emission as previously described. It is noted that CNT_b[n:0] corresponds to an inverse of the CNT[n:0] and is used to compare an inverted output from inverter pairs  496  to an inverted bit of CNT[n:0]. 
     It should be appreciated that in some embodiments counting circuitry may decrement, a comparator  490  may output a logical low value if every bit matches, or any combination thereof. In other words, a variety of valid embodiments may apply described memory-in-pixel techniques. Furthermore, an optional transistor  500  may be included in a sub-pixel  72  to provide power-saving benefits from precharging a common output (e.g., MTCH) node of the comparator  490  thereby making the circuitry more responsive to changes in the output from the comparator  490 . 
     To elaborate on operation of the sub-pixel  72  depicted in  FIG. 21 , a process  520  for operating a sub-pixel  72  having a comparator  490  and memory circuitry  491  is described in  FIG. 22 . Generally, the process  520  includes initializing memory circuitry (block  522 ), precharging common output from comparator (block  524 ), incrementing count of counting circuitry (block  526 ), causing emission based on automatic comparator determination stored in memory circuitry (block  528 ), determining if counting circuitry has reached a maximum count (block  530 ). In response to the counting circuitry reaching the maximum count, preparing for next image (block  532 ), and in response to the counting circuitry not reaching the maximum count, precharging the common output from the comparator (block  524 ). In some embodiments, the process  520  may be performed at least in part by executing instructions stored in a tangible, non-transitory, computer-readable medium, such as one or more storage devices  14 , using processing circuitry, such as processing core complex  12 . Additionally or alternatively, the process  461  may be implemented at least in part based on circuit connections formed in display controlling circuitry, such as a row driver  60 , a column driver  62 , and/or a timing controller  54 . 
     Thus, in some embodiments, a row driver  60  may initialize memory circuitry  492  (block  522 ). To initialize the memory circuitry  492 , the row driver  60  may enable a control signal to force a node of the memory circuitry  492  to a low voltage value. Taking  FIG. 21  for example, to initialize the memory circuitry  492 , a row driver may enable an S reset (S_rst) signal to reset a voltage value of a node (e.g., S node) of the memory circuitry  492 . Initializing the node of the memory circuitry  492  enables the light-emitting circuitry to emit until the comparator outputs a logical high to stop light emission from the sub-pixel  72  (e.g., in response to the gray level stored in memory being reached by the counting circuitry). In other words, for one or more sub-pixels  72  implementing a comparator  490 , sub-pixels  72  may start light emission together at the same time but stop light emission at different times—where the respective duration of light emission corresponds to a target gray level for the respective sub-pixel  72 . 
     The row driver  60  may precharge a comparator  490  after initializing the memory circuitry  492  (block  524 ). To precharge the comparator  490 , the row driver  60  may enable a precharge signal to cause a voltage to boost the circuitry, thus enabling the sub-pixel  72  to be more responsive to changes in output from the comparator  490 . To precharge the comparator  490 , the row driver  60  may enable a “Precharge” signal that works in conjunction with an inverse emit_en signal  420  to cause a voltage (e.g., DVDD) to transmit through to the comparator  490  (e.g., the MTCH node of the comparator  490 ) to boost the circuitry. Although specific circuitry is depicted that operates to precharge the comparator  490  in response to the Precharge signal, it should be appreciated that a variety of valid circuitry arrangements may be used to facilitate precharging the comparator  490 . 
     After precharging the comparator  490 , the row driver  60  may increment a count of counting circuitry (block  526 ). The row driver  60  may increment counting circuitry, for example, in response to a clocking signal timing the incrementing. After incrementing the counting circuitry, the sub-pixel  72  automatically determines if the count of the counting circuitry equals or exceeds a value represented by the stored DATA  412 . This occurs because the individual bits of the count and the individual bits of the DATA  412  are respectively transmitted to the comparator  490 , where the comparator  490  outputs a logical high value if all of the bits match or a logical low value if even one bit does not match. The comparator  490  output transmits for storage, or memorization, in inverter pair  498  of the memory circuitry  492 , where the value is stored until the row driver  60  enables emission via enabling of emit_en signal  420 . 
     After incrementing the count of counting circuitry, the row driver  60  causes emission based on the output from the comparator  490  determination stored in the memory circuitry  492  (block  528 ). The row driver  60  causes emission through enabling the emit_en signal  420 . As described earlier, upon the enabling of emit_en  420 , the value transmits from the inverter pair  498  to the LED driver and light-emitting circuitry of the sub-pixel to cause light emission, for example, from a LED  230  or any suitable light-emitting circuitry. The value transmitted from the memory circuitry  492  may activate or deactivate switching circuitry of the LED driver and light-emitting circuitry responsible for causing light emission. 
     Upon the row driver  60  causing emission based on the output from the comparator  490 , the row driver may determine if the count of the counting circuitry is a maximum count (block  530 ). Counting circuitry may count from a minimum to a maximum value, for example, from 0 to 255. Thus, when a maximum value, or a maximum count, is reached by counting circuitry, the row driver  60  may perform certain processing steps to restart the count. 
     In response to the maximum count not being reached, the row driver  60  restart the process  520  by precharging the common output from the comparator  490  (block  524 ). Thus, from there, the process  520  continues as described to cause the row driver  60  to transmit another output from the comparator  490  indicative of if the stored DATA  412  equals or exceeds a count represented by the counting circuitry. 
     However, in response to the maximum count being reached, the row driver  60  prepares for the next image (block  532 ). To do this, the row driver  60  prepares to receive new DATA  412  corresponding to the target gray level of the sub-pixel  72  used to communicate a next image. Different embodiments of sub-pixels  72  may prepare in varying ways. For example, the sub-pixel  72  from  FIG. 21 , may enable one or more write_en signals  494  to facilitate in loading of new DATA  412  into the memory circuitry  491 . In some embodiments, preparing for a next image includes restarting a count of the counting circuitry such that at block  526  the counting circuitry increments to zero and the counting may restart. It should be appreciated that in embodiments where counting circuitry is a series of flip-flops coupled together to form a counter, such as the counter  130 , restarting the counting circuitry to zero is unnecessary as the counting circuitry automatically restarts itself to zero based on the digital logic properties of the circuitry. 
     Several emission schemes, such as binary pulse width modulation and single pulse width modulation, have been described with respect to general theory of operation, specific example memory circuitry, and specific example pixel circuitry to enable use of the emission scheme to generate a perceived gray level of light emitted from a sub-pixel. An additional emission scheme may be performed by using memory-in-pixels techniques—a binary pulse width modulation reordering emission scheme. 
     To help illustrate, memory circuitry  560  having one or more MWRs  406 , one or more MSELs  410 , inverter pairs  408 , inverter pair  498 , and a switch/reset (SR) latch  562  is shown in  FIG. 23 . A row driver  60  may work in cooperation with a column driver  62  to provide DATA  412  to the memory circuitry  560  for storage prior to transmission to a light-emitting portion of a pixel as a CSimage.data signal  247 , for example, by enabling control signals to permit the column driver  62  to store DATA  412  in memory circuitry  560 . 
     Generally, a row driver  60  may operate the memory circuitry  560  to emit multiple bits of data from memory at the same time to the same node, for example, node BP_pre. In this way, the row driver  60  may modulate emission times to rearrange bit order represented by DATA  412 . For example, if DATA  412  equals 0010, the row driver  60  may operate the memory circuitry  560  to cause emission to follow 1-0-0-0 such that the emission time for the “1” occurs first and is not emitted after the time period corresponding to “00.” This rearranging may improve appearances of visual artifacts on an electronic display  18  while still causing the same gray level as “0010” to emit from the sub-pixel. 
     Elaborating further on the reordering associated with the binary pulse width modulation reordering emission scheme,  FIG. 24A  shows a bit-plane graph  580 ,  FIG. 24B  shows an error graph  588 ,  FIG. 24C  shows a bit-plane graph  582 ,  FIG. 24D  shows an error graph  590 ,  FIG. 24E  shows a bit-plane graph  584 ,  FIG. 24F  shows an error graph  592 ,  FIG. 24G  shows a bit-plane graph  586 , and  FIG. 24H  shows an error graph  594 , where  FIG. 24  as a whole illustrates the effects reordering on total error.  FIG. 24A - FIG. 24H  represent simulated performance of an electronic display  18  implementing the binary pulse width modulation emission scheme with and without reordering for a six-bit binary number representing a target gray level for a sub-pixel and/or a pixel. 
     The bit-plane graph  580  shows an original sequence of the binary pulse width modulation emission scheme without any reordering for gray levels represented by six bits, where for all the bit-plane graphs  580 ,  582 ,  584 , and  586  have a light portion  595  corresponding to light emission and a dark portion  596  corresponding to no light emission. The bit-plane graph  580  is caused by a row driver  60  operating a sub-pixel  72  to emit light via binary pulse width modulation (e.g., LED  230  is driven to emit light in response to binary representations of least to most significant bits without reordering, such that 0101 emits light following 1-0-1-0). Each square of a bit-plane graph shows a relative significance of a particular bit in a particular position shown in terms of a bit-plane used to cause a particular gray level ranging from a minimum gray level  598  (corresponding to an all dark portion  596  for all bit-plane values) to a maximum gray level  599  (corresponding to an all light portion  595  for all bit-plane values). For example, block  597 , representing a most significant bit of bit-plane graph  580 , is a logical high for gray levels from 32 to 64, and is a logical low for gray levels from 0 to 32. This is consistent with six-bit binary representations of those decimal values. Further, all bit planes are logical low and the gray level of 0 and all are logical high at the gray level of 64. These binary states correspond to the numerical representations of the gray level in binary, for example, to make a gray level of 0, one expects that all bit-planes are logical low, or 000000. Thus, bit-plane graphs may visually represent a relative importance of a bit to representing gray levels (e.g., in bit-plane graph  580 , the state of the sixth bit changes the gray level value in a more dramatic way than a first, or least significant, bit). 
     When sub-pixels  72  are operated to emit light following a binary pulse width modulation emission scheme without reordering, total error counts are high (e.g.,  322 ) as shown in bit-plane graph  580  and error graph  588 . It may be desired to lower the total error counts through reordering because errors manifest on an electronic screen of an electronic display  18  as, for example, dynamic false contouring, color breakup, and/or flickering of light emitted from one or more pixel. 
     As reordering occurs and as the most significant bits are reordered to emit first to cause gray levels of the bit-plane graphs, as seen with bit-plane graph  582  and bit-plane graph  584 , the bit-plane pattern trends towards looking like the ideal bit-plane shown in bit-plane graph  586 . In addition, error decreases as reordering occurs as shown with error graph  588 , error graph  590 , error graph  592 , and error graph  594 . Perceived image quality may improve from decreasing error counts via the reordering of the bit-planes. The ideal case (e.g., bit-plane graph  586 ) shows how the bit-plane graph  586  trends to a gradual bit-plane change as gray level increases and how the total error trends to a number of total states represented by the bit-plane (e.g., 6 bits corresponds to 64 total states, following the relationship: number of states=2 n , where n is the number of bits) through increasing a number of reorderings. 
     Referring back to  FIG. 23  to elaborate on how a row driver  60  operates memory circuitry  560  to perform a binary pulse width modulation reordering emission scheme, the row driver  60  enables and/or disables control signals to coordinate transmission of reordered DATA  412  from memory circuitry  560 . For example, the row driver  60  may selectively enable and/or disable Sel signals  415  to transmit respective bits from inverter pairs  408 . In some embodiments, the row driver  60  may selectively enable and/or disable the Sel signals  415  in response to a bit-plane clock  106  that defines emission periods for the bit positions of DATA  412 . 
     At a high level and for the case of ideal reordering, the row driver  60  may operate the memory circuitry  560  to transmit DATA  412  in an order of most significant bit to least significant bit as the CSimage.data signal  247  to cause light emission from the sub-pixel  72 , unless a bit of DATA  412  is a logical low. If a DATA  412  bit is a logical low, the row driver  60  effectively operates the memory circuitry  560  to skip the logical low emission period and to emit light according to a next logical high emission period. Upon transmission of all logical high bits represented in DATA  412 , the row driver  60  pauses for an equivalent duration to the total emission period of the logical lows, or in some embodiments, proceeds to process new DATA  412  for emission. For example, referring to emission reordering example  600 , if DATA  412  equals 1111, CSimage.data signal  247  transmits from memory circuitry  560  as “1111” having the same total emission period as “1111,” while if DATA  412  equals “0011,” transmitted CSimage.data signal  247  from memory circuitry  560  equals “1100” with respective bits having the same emission period as “0011,” and if DATA  412  equals “0100,” the data is recorded into “1000” for transmission as CSimage.data signal  247 . Ultimately, a single pulse width of light emission is created from data corresponding to a binary pulse width modulation emission scheme. 
     During reordering, the row driver  60  may operate the memory circuitry  560  to either emit a bit or to ignore a bit if the stored bit in memory is zero. The row driver  60  may operate in several different operational modes based on the number of reorderings the row driver  60  is to perform. For example, in the case of one reordering, the row driver  60  may have two operational modes while in the case of three reorderings, the row driver  60  may have eight operational modes. 
     The row driver  60  may determine which operational mode to operate in based at least in part on a comparison of a current emission time to a quadrant time. The row driver  60  may compare a current time to predefined time frames defining the operational mode (e.g., a first operational mode corresponds to a first length of emission). These different operational modes may define how the row driver  60  is to prioritize image data to cause emission. For example, for a one reordering example, a row driver  60  in a first operational mode may permit light emission according to the bit-plane (e.g., bit-plane meaning how a pixel is normally operated to emit light in response to binary states of image data used to operate the switch  104 ) if a first most significant bit equals the binary state “0,” however if the first most significant bit equals the binary state “1,” the row driver  60  may permit light emission regardless of the light emission defined by the bit-plane to cause reordering of the bit-plane to occur. 
     For each operational mode, regardless of the number of reorderings, the row driver  60  may perform similar control actions. The row driver  60  in each operational mode operates to iterate through each bit of DATA  412  starting with the least significant bit (e.g., DATA[0]  412 A) and proceeding to the bit prior to the most significant bit corresponding to the number of reorderings (e.g., DATA[n−1]  412  for one reordering, DATA[n−2]  412  for two reorderings). For each iteration, starting with DATA[0], the row driver  60  resets the S node, precharges the memory circuitry  560 , enables the Sel signal  415 B permitting transmission of the DATA[n]  412 B bit to SR latch  562 , and enables the Sel signal  415  corresponding to a current iteration of the least significant bit, such that either the most significant bit or the current iteration of the least significant bit transmits as CSimage.data signal  247 . 
     A row driver  60  may operate memory circuitry  560  differently based on the operational mode. For example, if the row driver  60  operates in the first operational mode, the row driver  60  additionally precharges the memory circuitry  560  between enabling of the Sel signal  415 B permitting transmission of the DATA[n]  412 B bit to SR latch  562 , and enables the Sel signal  415  corresponding to a current iteration of the least significant bit. Additionally or alternatively, for operational modes other than the first operational mode, the row driver enables the Sel signal  415 B, enables other Sel signals  415  corresponding to a number of most significant bits equal to the number of reorderings (e.g., Sel signals  415  for DATA[n]  412 B and for DATA[n−1]  412  for two reorderings, Sel signals  415  for DATA[n]  412 B, DATA[n−1]  412 , and DATA[n−2]  412  for three reorderings), and ends by enabling the Sel signal  415  corresponding to a current iteration of the least significant bit (e.g., DATA[0]  412 A for first iteration, DATA[1]  412  for second iteration, DATA[2]  412  for third iteration). 
     Thus, for an example of two reorderings, the row driver  60  may operate in four different operational modes for stored DATA  412  having six bits. For the first operational mode (e.g., corresponds to a first quarter of gray level values between zero and the gray level threshold, 16), the row driver  60  may reset the S node, precharge (e.g., enable Precharge signal  416 ), enable Sel[6]  415  and enable SET signal  602 , precharge, enable Sel[5]  415  and enable SET signal  602 , precharge, and enable the Sel[n]  415  (e.g., for a first iteration, n=0, Sel[0]  415 A is enabled) in addition to the SET signal for each bit of DATA  412 , incrementing the value of n from zero each iteration until reaching DATA[4]  412 . For the second operational mode (e.g., corresponds to a second quarter of gray level values between gray level threshold, 16, and two times the gray level threshold, 32), the row driver  60  may reset the S node, precharge, enable Sel[6]  415 B and enable SET signal  602 , precharge, enable Sel[5]  415 , and enable the Sel[n]  415  in addition to the SET signal for each bit of DATA  412 , incrementing the value of n from zero each iteration until reaching DATA[4]  412 . For the third operational mode (e.g., corresponds to a third quarter of gray level values between two times the gray level threshold, 32, and three times the gray level threshold, 48), the row driver  60  may reset the S node, precharge, enable Sel[6]  415 B, enable Sel[5]  415  and enable SET signal  602 , precharge, enable Sel[6]  415 B, and enable the Sel[n]  415  in addition to the SET signal for each bit of DATA  412 , incrementing the value of n from zero each iteration until reaching DATA[4]  412 . For the fourth operational mode (e.g., corresponds to a fourth quarter of gray level values between three times gray level threshold, 48, and four times the gray level threshold, 64), the row driver  60  may reset the S node, precharge, enable Sel[6]  415 B, enable Sel[5]  415 , and enable the Sel[n]  415  in addition to the SET signal for each bit of DATA  412 , incrementing the value of n from zero each iteration until reaching DATA[4]  412 . 
     To explain differently,  FIG. 25  includes a bit-plane graph  604  representative of a binary pulse width modulation emission scheme with two reorderings implemented with three color channels. As depicted, the bit-plane graph  582 , which corresponds to the two reoderings, is represented in the bit-plane graph  604  over time and with three color channels of one pixel  70 . The row driver  60  may time emissions in terms of quadrants, where, for a two-reordering case, one quadrant  606  may approximately correspond to one-fourth of emission time (e.g., ½ n , where n is equal to the number of reorderings). These quadrants  606  may parallel the previously described operational modes. As the time increases, the electronic display  18  may change emission priority—in other words, higher emission priority may be given to the two most significant bits of image data for a particular pixel  70  during emission than is given to the other bits. The electronic display  18 , in some embodiments, may manage emission based on a comparison of the most significant bits to a value represented by a counter, incrementing up from binary state “00” to binary state “11” on an edge (e.g., rising or falling edge) a clocking signal (e.g., where one period of the clocking signal corresponds to the duration of one quadrant). Thus, in these embodiments, in terms of the sub-pixels  72  of the pixel  70 , for the first quadrant  606 A, if the two most significant bits (MSBs) equal binary state “00,” the sub-pixel  72  may emit according to the bit-plane  608  (e.g., according to binary data as stored in memory  78  represented by the, but if the two most significant bits equal binary states “11,” “01,” and/or “10,” the sub-pixel emits light for the duration of the channel&#39;s emission period (e.g., a first color channel corresponds to time duration  609 ) of the first quadrant  606 , as generally summarized in output logic outline  610 . 
     To summarize the other three quadrants, the sub-pixel  72 , while operating in a second quadrant  606 B, emits light according to the bit-plane  608  if the two most significant bits equal binary state “01,” emits light if the two most significant bits equal binary state “10” and/or “11,” and does not emit light if the two most significant bits equal binary state “00.” While operating in a third quadrant  606 C, the sub-pixel  72  emits light according to the bit-plane  608  if the most significant bits equal binary state “10,” emits light if the two most significant bits equals “11,” and does not emit light if the two most significant bits equal “00,” and/or “01.” Additionally, while operating in a fourth quadrant  606 D, the sub-pixel  72  emits light according to the bit-plane  608  if the two most significant bits equal binary state “11,” and does not emit light if the two most significant bits equal “00,” “01,” and/or “10.” Thus, in this way, the sub-pixel  72  is operated to reorder light emission corresponding the two most significant bits such that the light emission of the two most significant bits occurs before light emission according to the bit-plane  608 . 
     To help provide content,  FIG. 26  depicts timing diagram of the binary pulse width modulation emission scheme with two reorderings implemented with the three color channels. This timing diagram shows the relationship between the loading of digital data into the memory  78  that occurs substantially simultaneously to other actions performed by the row driver  60 . For example, data loading of the green channel&#39;s most significant bits occurs at a time  612  of the emission of the red channel&#39;s least significant bit. Comparing  FIG. 26  to  FIG. 25 , just as was described for the fourth quadrant  606 D, the row driver  60  permits the sub-pixel  72  to emit light according to the bit-plane represented by data stored in and transmitted from the memory  78 . As is indicated on the timing diagram, the total emission period for all three color channels is approximately equal to three time times the channel-specific emission period. 
     An example embodiment of a pixel operated by a row driver  60  to follow a binary pulse width modulation reordering emission scheme including memory circuitry  560 , MWRs  406 , MSELs  410 , inverter pairs  408 , inverter pair  498 , a SR latch  562  coupled to analog driver circuitry  561  is shown in  FIG. 27 . This figure is meant to be example and not limiting, for example, a variety of pixel circuitry and analog driving circuitry may be used in conjunction with memory circuitry  560  and memory-in-pixel techniques.  FIG. 27  shows an example of memory circuitry  560  as applied to a digital mirror display (DMD). 
     Generally, the depicted memory circuitry  560  operates to receive DATA  412  corresponding to a target gray level for a color channel of the pixel  70  corresponding to the memory circuitry  560 . As illustrated, the memory circuitry  560  includes different color groups of memory for each color channel. In this embodiment, the pixel  70  has memory circuitry for each color channel instead of unique sub-pixels  72  for each color channel (e.g., R-G-B). A row driver  60  may operate the color channels via enabling a color group (CG) signal  564 . Upon activation of a CG transistor (MCG)  565 , stored DATA  412  transmits towards the analog driver circuitry  561 . The row driver  60  may permit one color channel to transmit at a time. Thus, the depicted memory circuitry  560  facilitates color sequential output from individual memory circuitry to shared output circuitry coupled to a DMD electrode. 
     A row driver  60  may operate the depicted memory circuitry  560  similar to memory circuitry  560  of  FIG. 23 . Thus, for an example of two reorderings, the row driver  60  may operate in four different operational modes, where the operational mode is selected based on the gray level value of DATA  412 . After writing DATA  412  to the inverting pairs  408 , the row driver  60  operates memory circuitry  560  to transmit stored DATA  412  to SR latch  562  a bit at a time to drive a DMD electrode through analog driver circuitry  561 . The row driver  60  may reorder DATA  412  to create a single pulse width modulated signal from a binary pulse width modulation emission data by selectively enabling and/or disabling CG signals  564  (e.g., enabling  564 B to transmit red data corresponding to bit-plane  7 ) by driving memory circuitry  560  with different operational modes. 
     For example, and as described above, for a first operational mode (e.g., corresponding to gray levels between zero and the gray level threshold), the row driver  60  may reset the S node, precharge, enable Sel[n]  415 B and enable SET signal  602 , precharge, enable Sel[n−1]  415  and enable SET signal  602 , precharge, and enable Sel[0]  415 A. The row driver may repeat the first operational mode for each bit of DATA  412 , incrementing from a first bit, DATA[0]  412 A until reaching DATA[n−2] (e.g., where 2 corresponds to a number of reordering). The row driver  60  may operate as described in discussions for  FIG. 23  while in the second, third, and fourth operational modes. 
     Similar to  FIG. 27 , an example embodiment of a pixel  650  operated by a row driver  60  to follow a single pulse width modulation emission scheme including memory circuitry  654 , color channel selection transistors  656 , inverter pair  498 , analog driver circuitry  561 , and a comparator  490  electrically coupled to light-emitting circuitry (not pictured) is shown in  FIG. 28 . This figure is meant to be example and not limiting, for example, any suitable pixel circuitry may be used in conjunction with memory circuitry and memory-in-pixel techniques, such as, any combination of additional and/or alternative embodiments of suitable switching elements (e.g., depicted MOSFETs).  FIG. 28  is included to show an example of a pixel  650  as applied to a liquid crystal display (LCD) and operation of the memory circuitry  654  and the comparator  490  may generally follow the process depicted and described with  FIG. 22 . 
     Generally, the pixel  650  receives DATA  412  during a data writing process managed by a row driver  60  enabling a write_en signal  414  to permit writing of DATA  412  bits into memory, for example, inverter pairs  408 . During the data writing process, the pixel  650  receives gray level digital data for the red color channel (DATA)  412 R, gray level digital data for the green color channel (DATA)  412 G, and receives gray level digital data for the blue color channel (DATA)  412 B, where the pixel  650  receives the DATA  412  in a series data transmission and/or in a parallel data transmission to each of the memory circuitry  654 . Upon DATA  412  being written into the memory of the pixel  650 , the comparator  490  performs an automatic comparison of DATA  412  from memory to a count transmitted from counting circuitry, such as, counter  130  and/or any suitable counting method. Using the same methods described with comparator  490  from  FIG. 21 , the comparator  490  transmits a “1” if the DATA  412  and the count  658  from counting circuitry are the same (e.g., matches all bits) or transmits a “0” if not equal (e.g., one or more bits do not match). The row driver  60  transmits a CG signal  564  to a respective transistor of the color channel selection transistors  656  to enable a color channel for color sequential emission, for example, either red, green, or blue color channel for emission via the shared output stage. Upon the row driver  60  enabling transmission from a color channel, the MTCH bit transmits through to memory circuitry  492  for storage. The row driver  60  may enable the EMIT signal to permit light emission according to the stored MTCH bit, as previously described. Additionally or alternatively, the row driver  60  may enable a GHOST signal that at least in part causes no emission to occur, regardless of the stored MTCH bit in memory circuitry  492 . To emit light, the row driver  60  enables the EMIT signal, causing the stored MTCH bit to transmit to analog driver circuitry  561  coupled to a high reference voltage and a low reference voltage. The stored MTCH bit transmits to the analog driver circuitry  561  either activating and/or deactivating MS  566  coupled to a LC electrode responsive to the reference voltages (e.g., MS  566 A, MS  566 B). The reference voltages, though depicted as 5[V] and VSS, may be any suitable voltage used to drive the LC electrode upon activation of MS  566 . 
     Following structure described above, the pixel  650  may be operated to emit according to a single pulse width modulation emission scheme. Different embodiments may be operated by a row driver  60  to emit according to the different emission schemes. For example, a color channel of the pixel  650  may be operated according to the binary pulse width modulation emission scheme generally if the digital data transmitted to the pixel  650  changes and the comparator  490  is removed. 
     As has been discussed throughout this disclosure, it should be understood that memory-in-pixel techniques are valid for a variety of embodiments and display technologies. It should also be understood that for each reference voltage discussed, or disclosed in the figures, additional or alternative reference voltages may be used. Additionally or alternatively, it is noted that although described as reducing or eliminating a reliance on using a frame buffer, memory-in-pixel techniques may be used in tandem with a frame buffer in some embodiments. Furthermore, although memory circuitry has been described as storing six bits, twelve bits, eight bits, and/or sixteen bits, it should be appreciated that any suitable memory structure may be used to store any suitable number of bits. 
     As briefly discussed in  FIG. 21 , slight adjustments to the memory-in-pixel techniques may be generally applied to permit moving the memory  78  into a smart buffer, as opposed to or in addition to including the memory  78  in the sub-pixel  72  itself.  FIG. 29  shows this generally with a memory-in-pixel architecture electronic display  700  and a smart buffer architecture electronic display  702 . The memory-in-pixel architecture electronic display  700  includes, as depicted, memory  78  in each sub-pixel  72  located in an active area  704  of the electronic display  18 , where the active area  704  includes all the light-emitting components of the electronic display and communicative couplings to support data transmission to the light-emitting components. In the memory-in-pixel architecture electronic display  700 , digital data is transmitted from memory  708  (e.g., DRAM or SRAM memory) to each respective sub-pixel  72  for localized buffering in the memory  78 . In some embodiments, the digital data transmits from the memory  708  to a source area  710  before transmission into the memory  78  for localized buffering (e.g., buffering within the sub-pixel  72 ). However, substantially similar memory as memory  78  may be included in a smart buffer  712  of the smart buffer architecture electronic display  702  to still eliminate, or at least reduce, a reliance upon a frame buffer but additionally remove the memory  78  from the active area  704 . By moving the memory  78  into a smart buffer  712 , the row driver  60  may use operate an input latch  714  and an output latch  716  to arbitrate light emission from each sub-pixel  72  via analog out circuitry, for example, the driver  80 . Here, the smart buffer  712  may represent any suitable buffer memory disposed in an integrated circuit of the electronic display  18  but outside of the active area of the electronic display  18 . 
       FIG. 30  shows an example of the smart buffer embodiment of the memory  78  circuitry including memory circuitry  750 , a comparator  752 , memory circuitry  754 , and an output inverter  756 . This circuit functions similarly to memory circuitry shown in  FIG. 21 , where the smart buffer of  FIG. 30  receives digital data in response to a write enabled (write_en) control signal  757  permitting the writing of the digital data to the memory circuitry  750  (e.g., inverter pair). Thus, the general operation of the memory circuitry  754  and the comparator  752  may generally follow the process depicted and described with  FIG. 22 . The smart buffer of  FIG. 30  may have a memory  78  circuit for each sub-pixel  72  of the active area  704 . The digital data value may be stored in the memory circuitry  750  until a new value of digital data is written into the smart buffer for the particular sub-pixel  72 . 
     When the digital data is transmitted into the memory circuitry  750 , the comparator  752  determines if all bits of the digital data match an output (CNT/CNT_b) from counting circuitry. Similar to previously described embodiments, the counting circuitry counts to permit light emission according to the grey level represented by the digital data. The comparator may output a logical zero, “0,” as the MTCH bit until the digital data matches the count—at which point, the comparator outputs a logical one, “1” as the MTCH bit. The MTCH bit generally transmits to the memory circuitry  754  to be stored while the value of the inverted MTCH bit transmits onto the output inverter  756  and ultimately onto a corresponding sub-pixel to cause and/or stop light emission. 
     Continuing on with the transmission path of the MTCH bit,  FIG. 31  depicts pixel circuitry  780  that may be used in conjunction with the smart buffer circuitry of  FIG. 30 . The pixel circuitry  780  includes an input latch  782  (e.g., inverter pair) and an output latch  784  (e.g., inverter pair) that are both operated to latch digital data transmitted from a smart buffer, for example the smart buffer  712 , in response to a write_enabled (write_en) control signal  786 . Upon latching, the digital data may be automatically transmitted to a gate of a driving transistor  788 . Similar to previously discussed, the driving transistor  788  is activated in response to the digital data, depending on the value of the digital data, and causes a driving current to transmit through light-emitting circuitry, for example, a light-emitting diode  790 , of the pixel circuitry  780 . 
     Accordingly, technical effects of the present disclosure include techniques for implementing memory in one or more pixels of an electronic display to improve processing techniques of image data for presentation. The techniques include systems and methods for receiving image data, storing the image data in memory in the pixel, and transmitting the image to a driver circuit to operate a light-emitting element of a pixel to emit light. Furthermore, any suitable pixel circuitry implementing memory-in-pixel techniques may be used to execute different emission schemes including a binary pulse width modulation emission scheme, binary pulse width modulation reordering emission scheme, a single pulse width modulation emission scheme, and a pulse density modulation emission scheme, while still benefitting from decreasing bandwidths used to communicate a same image as without using memory-in-pixel techniques. These pixel circuits enabling the emission schemes may couple to a pixel circuit having a hybrid drive to increase a responsiveness to electrical signals of an LED. 
     The techniques described herein may be applied and integrated with a variety of display technologies and should not be limited to the specific embodiments depicted and/or described herein. For example, pixels with memory are shown as having a light-emitting diode as a light-modulating device, however, the memory-in-pixels techniques may be generally applied to different pixel circuitry to support a variety of display technologies that use a variety of light-modulating devices. In this way, suitable pixel circuitry supporting light emission via a light-emitting diode, a digital mirror display, an organic light-emitting diode, or circuitry supporting a liquid crystal display, a plasma display, or a dot-matrix display may each have memory in the pixel to achieve at least improvements to data transmission bandwidths and ease of programming the pixels. 
     The specific embodiments described above have been shown by way of example, and it should be understood that these embodiments may be susceptible to various modifications and alternative forms. It should be further understood that the claims are not intended to be limited to the particular forms disclosed, but rather to cover all modifications, equivalents, and alternatives falling within the spirit and scope of this disclosure. 
     The techniques presented and claimed herein are referenced and applied to material objects and concrete examples of a practical nature that demonstrably improve the present technical field and, as such, are not abstract, intangible or purely theoretical. Further, if any claims appended to the end of this specification contain one or more elements designated as “means for [perform]ing [a function] . . . ” or “step for [perform]ing [a function] . . . ”, it is intended that such elements are to be interpreted under 35 U.S.C. 112(f). However, for any claims containing elements designated in any other manner, it is intended that such elements are not to be interpreted under 35 U.S.C. 112(f).