Abstract:
A tablet cover ( 100 ) and circuitry ( 400 ) provide for convenient connection of a tablet ( 105 ) or other personal electronic device to additional memory, functions, and features as provided by an internal device ( 215 ) and/or an external device ( 160 ). The circuitry selectively connects the tablet, the external device, and the additional memory together. The additional memory is internal to the case and is thereby protected from loss or damage due to accidental impact.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the priority of U.S. Provisional Patent Application No. 61/945,379, filed Feb. 27, 2014, and titled “Tablet Case With On-The-Go USB Port”, the entire disclosure and contents of which are hereby incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    A “tablet” is typically considered to be a general-purpose computing device, usually contained in a single panel, and using a touch screen as the input device and as the display device. The preceding sentence is to indicate the general nature of a tablet, is not a definition, and is not limiting, as other functions, features, and capabilities may be provided in, or for use with, a tablet. 
         [0003]    Some tablets have a micro-USB “on-the-go” or “OTG” port. The OTG port allows the tablet to switch back and forth between the roles of a host device or a client device. For example, if a memory card is plugged into the OTG port, the tablet acts as a host device to write to and/or read from the memory card, but the tablet then acts as a client device, such as a USB Mass Storage Device, when the tablet is connected to a host computer via the OTG port. If, however, some information in the tablet memory is to be transferred to both a memory card and a host computer, then multiple operations are required: the memory card must be plugged in, the information transferred, the memory card unplugged, the host computer plugged in, the information transferred, and then the host computer unplugged. Likewise if information from a memory card and other information from a host computer are to be transferred to the tablet memory, then multiple operations are required. 
         [0004]    The standard internal memory of many devices, including but not limited to tablets, may be somewhat limited, however, thus making additional memory desirable or even necessary. Buying a larger internal memory at the time of purchase is often an expensive proposition at the consumer end, adding more internal memory after purchase may be difficult, extremely expensive, or even practically impossible, especially by the consumer, and a manufacturer may be reluctant to even provide the option or capability to add more memory. Thus, the consumer may be faced with the choice of paying substantially more at the time of purchase for additional internal memory, or of being resigned to the internal memory size that the consumer can afford at the time of purchase. Or, if the manufacturer provides an OTG port, the consumer can plug a memory card into the OTG port. In this case the memory card will extend from the tablet, thus making the memory card susceptible to accidental impact, which can result in the memory card being unplugged and lost, the memory card being damaged, and/or the tablet being damaged. 
       SUMMARY 
       [0005]    A tablet cover and circuitry provide for convenient connection of a tablet or other personal electronic device to additional memory, functions, and features as provided by an internal device and/or an external device. The circuitry selectively connects the tablet, the external device, and the additional memory together. The additional memory is internal to the case and is thereby protected from loss or damage due to accidental impact. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]      FIG. 1  illustrates front and edge views of an exemplary tablet case surrounding an exemplary tablet. 
           [0007]      FIG. 2  illustrates an embodiment of the circuitry of the tablet case. 
           [0008]      FIG. 3  illustrates alternative circuitry which has only a single switch or 3-port hub. 
           [0009]      FIG. 4  is a block diagram of an exemplary circuit board showing the various components thereon. 
       
    
    
     DETAILED DESCRIPTION 
       [0010]      FIG. 1  illustrates front and edge views of an exemplary tablet case  100  surrounding an exemplary tablet  105 . The tablet case  100  preferably, but not necessarily, has a front cover  110  which is connected to a back cover  120  via a hinge  115 . The front cover  110 , hinge  115 , and back cover  120  are preferably, but not necessarily, formed and manufactured as a single piece of flexible material. The tablet  105  has an on-the-go micro-USB port  130 , and another port  135  for connecting, by way of example and not of limitation, a power supply, headphones, an accessory, etc. The case  100  has an external USB port  125  which is preferably, but not necessarily, offset from the micro-USB port  130 ; that is, the port  125  is not in-line with the port  130 . Although a micro-USB port is referenced herein, that is merely a current implementation of a USB port or USB standard so the term “micro-USB port” should be understood to include future iterations of, and modifications to, USB ports and standards. The port  125  is configured to accept a USB plug  150  at one end of a USB cable  155  so as to connect a device  160  to the tablet  105 . The device  160  may be a host device, such as a computing device, or may be a memory device, a battery pack, a power supply, or other device which provides a feature, function, or capability useful with the tablet  105 . It is expected that, for most occasions, the device  160  will be a computing device so, for convenience of discussion below, the device  160  may sometimes be referred to as a computing device  160 . The tablet cover  100  is slightly larger than is necessary to accommodate the tablet  105  so as to provide space  140  for the electronic circuitry  200  discussed below with respect to  FIGS. 2 and 3 . 
         [0011]    Future iterations of the standard for the USB interface are expected to eliminate the host/client device distinction or relationship so that the interface will be truly bi-directional. That change, and other changes in the standard, only slightly alter the environment, and do not impact the functionality of the apparatus and techniques disclosed herein. 
         [0012]    The tablet cover  100  and electronic circuitry  200  provide for additional memory which expands the memory capability of the tablet, additional memory which does not have to be plugged in and then unplugged, additional memory which does not extend from the tablet and therefore will not be lost or damaged by an accidental impact, additional memory which does not monopolize the use of the OTG USB port, and the addition of other types of devices to enhance the functionality and/or features of the tablet. 
         [0013]      FIG. 2  illustrates an embodiment of the circuitry  200  of the tablet case  100 . The electronic circuitry  200  includes an external USB port  125 , an internal micro-USB plug  205 , a switch  210 , a USB 2-port hub chip  220 , and a device  215 . The device  215  may be a memory device or any other very small device which provides a feature, function, or capability useful with the tablet  105 , such as, but not limited to, a temperature sensor or an electronic compass. It is expected that, for most occasions, the device  215  will be a memory device so, for convenience of discussion below, the device  215  may sometimes be referred to as a memory device  215 . The external USB port  125 , which may be a standard USB OTG port, a mini-USB OTG port, or a micro-USB OTG port, is configured to accept a correspondingly-sized USB plug which may be connected to the computing device  160 . The internal micro-USB plug  205  is configured to plug into the micro-USB port  130  of the tablet  105  when the tablet  105  is installed into the cover  100 . The memory device  215  may be, for example, a compatible memory such, but not limited to, a Micro SD card. Switch  210  and hub  220  provide for interconnection between the tablet  105 , the computing device  160 , and the memory device  215 . 
         [0014]    If the computing device  160  is not present, switch  210  connects the tablet  105  to the device  215 . Alternatively, switch  210  could connect the tablet to hub  220  which, in turn, connects the tablet  105  to the device  215 . In either configuration, the tablet  105  has access to additional memory, information, features and/or functions as provided by the device  215 . 
         [0015]    If the computing device  160  is present, then hub  220  connects the computing device  160  to device  215  and to switch  210  which, in turn, connects the computing device  160  to the tablet  105 . Also, the switch  210  allows the tablet  105  to connect to the device  215  and to hub  220  which, in turn, connects the computing device  160  to the tablet  105 . 
         [0016]      FIG. 3  illustrates alternative circuitry  200  which has only a single switch or 3-port hub  320 , which allows the tablet  105 , the computing device  160 , and the device  215  to communicate with each other. For example, if computing device  160  is not present, hub  320  connects the tablet  105  to the device  215  so that the tablet  105  has access to additional memory, information, features and/or functions as provided by device  215 . If computing device  160  is present, then hub  320  connects the computing device  160 , tablet  105 , and device  215 . 
         [0017]    Thus, in both  FIGS. 2 and 3 , the tablet  105  can communicate with both the computing device  160  and the device  215 , and the computing device  160  can communicate with both the tablet  105  and the device  215 . This permits the user to modify the contents of the computing device  160  or the memory device  215  such as, but not limited to, adding a movie file to memory device  215  or copying or transferring an audio or video file from the memory device  215  to the computing device  160 . When the computing device  160  data cable  155  is removed, the switching circuitry (components  210 ,  220 ,  320 ) restores the on-the-go function whereby the tablet  105  has sole control of the memory device  215 . 
         [0018]    Thus, the computing device  160  can write to, and/or read from, both the tablet  105  and the additional memory device  215  without having to connect or disconnect anything other than the computing device  160 . Further, the tablet  105  has continuous access to the additional memory device or other device  105 . 
         [0019]    The presence or absence of a computing device  160  on port  125  can be detected by the hub  220  or  320  by detecting the presence or absence of a voltage on a pin of the port  125 , such as but not limited to one of the data pins  225  of the port  125 . The presence or absence of computing device  160  on port  125  can therefore cause the tablet  105  to switch between a “client” mode and a “host” mode. Optionally, as shown in  FIG. 2 , a pull-up or pull-down resistor  230  may be used to force a pin  225  to a particular voltage (V) or state when a device is not connected to the port  125 . 
         [0020]    Also as shown in  FIGS. 1-3 , the circuitry  200  components (switch  210 , hubs  220  and  320 , and memory  215 ) are preferably enclosed in the space  140  in the case  100 . There is preferably, but not necessarily, a small circuit board  400  (as shown in  FIG. 4 ) on which those components are mounted, or which has a connector into which a component, such as the memory device  215 , may be installed. 
         [0021]    Thus, when the user is away from his/her computing device  160 , the tablet  105  has access to the expanded memory of device  215  or the features or functions of another type of device which the tablet  105  can recognize and use without the device  215  extending from the tablet  105 . Then, when the user attaches the computing device  160  to the tablet  105  through the circuitry  200  of the tablet case  100 , the computing device has access to the tablet  105  and the device  215 , and the tablet  105  has access to the computing device  160  and the device  215 . Therefore, the tablet case  100  and circuitry  200  provide for convenient and expanded use of the tablet  105 . 
         [0022]    The device  160  may also be a battery pack or an additional memory. If device  160  is a battery pack, a memory, or a battery pack with memory, then the circuit(s)  210 ,  220 ,  320  connect(s) the device  160  to the tablet  105  via the port  205 . 
         [0023]    The plug  150  and port  125  may be standard USB components, mini-USB components, micro-USB components, other size components, or another type of plug/port. 
         [0024]      FIG. 4  is a block diagram of an exemplary circuit board  400  showing the various components  125 ,  205 ,  210 ,  215 ,  220 , and  230  thereon. Although components  210 ,  215 ,  220  and  230  are shown as separate components, it will be appreciated that any two, any three, or all four of them could be implemented as a single component and similarly if component  320  is used instead of components  210  and  220 . Optionally, the circuit board  400  is not used, and the various components are secured to the case and/or to each other by using a glue, for example, epoxy. 
         [0025]    In one embodiment, the component  240  may simply be an opening which allows access to the port  135  so that a user can directly insert a plug into the port  135 . The opening may be a space between the case  100  and one face of the circuit board  400 , or the opening may be a space between the side of the case  100  and one end of the circuit board  400 . In another embodiment the component  240  may be a female-male straight-through connector, the male end of which plugs into the port  135 , and the female end of which appears at the surface of the case  100  so that it is conveniently accessible to the user. 
         [0026]    Although the above discussion has been directed to a tablet  105 , it will be appreciated that the tablet cover  100  and circuitry  200  may also be used with other personal electronic devices, such as but not limited to smartphones. Further, although the above discussion has been directed to a USB port, it will be appreciated that the above-described circuitry and technique may also be used with other types of ports which provide at least the same functionality of a USB port which is used as described herein. 
         [0027]    Based on the foregoing, it should be appreciated that a tablet cover and circuitry which provide for convenient connection of the tablet to additional memory, functions, and features as provided by an internal device  215  and/or an external device  160  have been disclosed herein. Although the subject matter presented herein has been described in language specific to tablets, it is to be understood that the invention disclosed herein is not necessarily limited to the specific features, configurations, or components described herein. Rather, the specific features, configurations and components are disclosed as example forms. Further, all of the various features, configurations, and components need not be embodied in a single item to gain the benefits of other features, configurations, and components. 
         [0028]    The subject matter described herein is provided by way of illustration for the purposes of teaching, suggesting, and describing, and not limiting. Alternatives to the illustrated embodiment are contemplated, described herein, and set forth in the claims. Various modifications and changes may be made to the subject matter described herein without following the example embodiments and applications illustrated and described, and without departing from the true spirit and scope of the present invention.