Abstract:
A Universal Serial Bus (USB) converter circuit includes: a High Definition Multimedia Interface (HDMI) transceiver circuit, a signal converting circuit and a USB receptacle, wherein the HDMI transceiver circuit arranged to transmit/receive a HDMI signal, wherein the HDMI transceiver circuit includes at least a video signal and a plurality of processing signals; the signal converting circuit coupled to the HDMI transceiver circuit is arranged to execute a converting operation to processing a conversion between the plurality of processing signals and A USB signal; and the USB receptacle coupled to the signal converting circuit includes a USB signal pin and a set of video signal pin, wherein the USB signal is transmitted/received with an electronic device through the USB pin, and the video signal is transmitted/received with the electronic device through the set of video signal pin.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a Universal Serial Bus (USB) converter circuit, and more particularly, to a USB C-type interface—High Definition Multimedia Interface (HDMI) converter circuit and a related method. 
         [0003]    2. Description of the Prior Art 
         [0004]    Video Electronic Standard Association (VESA) proposed an USB type C—DP Alt mode for the USB type C interface being capable of supporting a display interface standard DisplayPort (DP) signal. However, considering that video devices, e.g. TV, Set Top Box (STB), etc. mainly support HDMI signal, there are some issues need to be overcame in order to implement the USB type C-HDMI converter circuit. For example, a simple USB type C—HDMI converter is not able to supply power and needs an extra converter for converting the HDMI signal to DP signal first, in which the transmitted/received data is no longer the original HDMI data. In addition, if the function of supplying power is required, devices need to convert the HDMI data to DP first then acquire the USB Power Delivery 2.0 function by the USB type C—DP Alt mode. Such implement needs two DP—HDMI converters results in the greatly increased manufacturing cost. Comparing to DP, HDMI further has few more signals such like Consumer Electronic Control (CEC) signal, Hot Plug Detection (HPD) signal and 5 volts signal, etc. Therefore, these problems need to be solved so the USB type C interface—HDMI conversion can be achieved. 
       SUMMARY OF THE INVENTION 
       [0005]    The present invention discloses a USB type C interface—HDMI converter and a related converting method to solve the aforementioned problem. 
         [0006]    According to an embodiment of the present invention, a USB converter circuit is disclosed, wherein the USB converter circuit comprises: a HDMI transceiver circuit, a signal converting circuit and a USB receptacle. The HDMI transceiver circuit is arranged to transmit/receive a HDMI signal, wherein the HDMI signal comprises at least a video signal and a plurality of processing signal; the signal converting circuit coupled to the HDMI transceiver circuit is arranged to execute a converting operation to process a conversion between the plurality of processing signals and a USB signal; and the USB receptacle coupled to the signal converting circuit comprises a USB signal pin and a set of video signal pin, wherein the USB signal is transmitted/received with an electronic device through the USB signal pin, and the video signal is transmitted/received with the electronic device through the set of video signal pin. 
         [0007]    According to an embodiment of the present invention, a signal converting and transmitting method is disclosed, wherein the method comprises: transmitting/receiving a HDMI signal, wherein the HDMI signal comprises at least a video signal and a plurality of processing signals; executing a converting operation to process a conversion between the plurality of processing signals and a USB signal; and utilizing a USB receptacle which comprises a USB signal pin and a set of video signal pin, wherein the USB signal pin is transmitted/received with an electronic device through the USB signal pin, and the video signal is transmitted/received with the electronic device through the set of video signal pin. 
         [0008]    These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  is a diagram illustrating an electronic device which comprises a USB converter circuit according to an embodiment of the present invention. 
           [0010]      FIG. 2  is diagram illustrating a USB converter circuit according to an embodiment of the present invention. 
           [0011]      FIG. 3  is a diagram illustrating a first connecting way according to an embodiment of the present invention. 
           [0012]      FIG. 4  is a diagram illustrating a second connecting way according to an embodiment of the present invention. 
           [0013]      FIG. 5  is a diagram illustrating a switching unit operating in the first connecting way according to an embodiment of the present invention. 
           [0014]      FIG. 6  is a diagram illustrating a switching unit operating in the second connecting way according to an embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0015]    Certain terms are used throughout the description and following claims to refer to particular components. As one skilled in the art will appreciate, manufacturers may refer to a component by different names. This document does not intend to distinguish between components that differ in name but not function. In the following description and in the claims, the terms “include” and “comprise” are used in an open-ended fashion, and thus should not be interpreted as a close-ended term such as “consist of”. Also, the term “couple” is intended to mean either an indirect or direct electrical connection. Accordingly, if one device is coupled to another device, that connection may be through a direct electrical connection, or through an indirect electrical connection via other devices and connections. 
         [0016]      FIG. 1  is a diagram illustrating an electronic device  100  which comprises a USB converter circuit  110  according to an embodiment of the present invention. As shown in  FIG. 1 , the USB converter circuit  110  installed in the electronic device  100  comprises a receptacle  120 , wherein the receptacle  120  is a USB type C interface receptacle, and the electronic device  100  connects with an electronic device  101  via a USB type C interface cable  130  through the receptacle  120 . Similarly, the electronic device  101  comprises a receptacle  121 , wherein the receptacle  121  is also a USB type C interface receptacle. In this embodiment, the electronic device  100  can be a TV or a USB C-type interface—HDMI converter, and the electronic device  101  can be a Set Top Box (STB), an Over The Top Box (OTT Box), etc. As shown in  FIG. 1 , the USB converter circuit  110  of the present invention can transmit the HDMI signal only via one USB type C interface cable without a USB type C—DP convert as a medium. The detailed architecture of the USB converting circuit  110  will be explained in the following paragraphs. 
         [0017]      FIG. 2  is a diagram illustrating USB converter circuit  110  according to an embodiment of the present invention. As shown in  FIG. 2 , except the receptacle  120  shown in  FIG. 1 , the USB converter circuit  110  further comprises a HDMI transceiver circuit  210 , a signal converting circuit  220  and a switching unit  230 , wherein the HDMI transceiver circuit  210  is arranged to transmit/receive a HDMI signal S 1  which comprises a HDMI video signal VS and a plurality of processing signals. In this embodiment, the plurality of processing signals comprise at least a Display Data Channel (DDC) signal, a Hot Plug Detection (HPD) signal, and a 5 volts voltage signal. The signal converting circuit  220  is arranged to convert the plurality of processing signals (DDC, HPD and 5 volts voltage signal) to a signal S 2 , wherein the signal S 2  corresponds to the USB 2.0 standard and is transmitted/received through a set of USB 2.0 pin USBpin of the receptacle  120  while the video signal VS comprised in the HDMI signal S 1  is transmitted/received through a set of video pin VSpin. It should be noted that the transmission/reception of the video signal VS is conducted through two pairs of transceiver pins of a USB type C receptacle, that is, the video pin VSpin has four pairs of pins. In addition, the HDMI signal S 1  further comprises a Consumer Electronics Control (CEC) signal. In an embodiment, the CEC signal is transmitted/received through a SideBand Use (SBU) pin of the receptacle  120 . However, it should not be a limitation of the present invention. In another embodiment, the CEC signal, the DDC signal, the HPD signal and the 5 volts voltage signal can be converted to the signal S 2  by the signal converting circuit  220  together then be transmitted/received through the USB2.0 pin. It should be noted that the connection between the USB type C receptacle and the USB type C interface cable allows reversible plug orientation, which means that the connection can be implemented in a first connecting way (which is the non-reverse plug orientation in this embodiment) or a second connecting way (which is the reverse plug orientation in this embodiment). Therefore, the receptacle  120  further comprises a detecting pin CC to detect the current connection between the USB type C receptacle and the USB type C interface cable is either in the first connecting way (non-reverse plug orientation) or the second connecting way (reverse plug orientation). When the connection is in the second connecting way (reverse plug orientation), the signal converting circuit  220  transmits a control signal CS to the switching unit  230  to make sure the correctness of the video signal VS. The detailed description will be explained in the following paragraphs. 
         [0018]      FIG. 3  is a diagram illustrating a first connecting way (non-reverse plug orientation) according to an embodiment of the present invention, wherein the video pin VSpin of the receptacle  120  comprises pins Pair 1 , Pair 2 , Pair 3  and Pair 4 . It should be noted that the locations of the video pin VSpin, the USB 2.0 pin USBpin and SBU pin and the relative locations between each pin shown in  FIG. 3  are only for illustrative purpose, not a limitation of the present invention. Besides, the receptacle  120  comprises not only those pins shown in  FIG. 3 . The skilled person in the art should understand the number, the locations and the purposes of pins comprised in a USB type C receptacle. The USB type C interface cable  113  is attached by a connector  300  corresponding to the USB type C interface, wherein the number of slots of the connector  300  shown in  FIG. 3  is only for illustrative purpose, not a limitation of the present invention. In addition, the connector  300  comprises not only those slots shown in  FIG. 3 . The skilled person in the art should understand the number and the purposes of slots of a connector corresponding to the USB type C interface. When the receptacle  120  and the connector  300  are connected in the first connecting way (non-reverse plug orientation), the slot A is going to be coupled to the pin Pair 1 , the slot B is going to be coupled to the pin Pair 2 , the slot C is going to be coupled to the pin Pair 3  and the slot D is going to be coupled to the pin Pair 4 .  FIG. 4  is a diagram illustrating a second connecting way according to an embodiment of the present invention. When the receptacle  120  and the connector  300  are connected in the second connecting way (reverse plug orientation), the slot D is going to be coupled to the pin Pair 1 , the slot C is going to be coupled to the pin Pair 2 , the slot B is going to be coupled to the pin Pair 3  and the slot A is going to be coupled to the pin Pair 4 . 
         [0019]      FIG. 5  is a diagram illustrating a switching unit  230  operating in the first connecting way according to an embodiment of the present invention. As shown in  FIG. 5 , the HDMI transceiver circuit  210  comprises corresponding pins Pair 1 ′, Pair 2 ′, Pair 3 ′ and Pair 4 ′, wherein the corresponding pin Pair 1 ′ is arranged to receive a first part VS 1  of the video signal VS, the corresponding pin Pair 2 ′ is arranged to receive a second part VS 2  of the video signal VS, the corresponding pin Pair 3 ′ is arranged to receive a third part VS 3  of the video signal VS, and the corresponding pin Pair 4 ′ is arranged to receive a fourth part VS 4  of the video signal VS. When the detecting pin CC detects the connection between the connector  300  and the receptacle  120  is in the first connecting way (non-reverse plug orientation), according to the control CS sent by the signal converting circuit  220 , the switching unit  230  couples the pin Pair 1  of the video pin VSpin to the corresponding pin Pair 1 ′ of the HDMI transceiver circuit  210  to transmit/receive the first part VS 1  of the video signal VS, couples the pin Pair 2  of the video pin VSpin to the corresponding pin Pair 2 ′ of the HDMI transceiver circuit  210  to transmit/receive the first part VS 2  of the video signal VS, couples the pin Pair 3  of the video pin VSpin to the corresponding pin Pair 3 ′ of the HDMI transceiver circuit  210  to transmit/receive the first part VS 3  of the video signal VS, and couples the pin Pair 4  of the video pin VSpin to the corresponding pin Pair 4 ′ of the HDMI transceiver circuit  210  to transmit/receive the first part VS 4  of the video signal VS. It should be noted that the HDMI transceiver circuit  210  comprises not only the corresponding pins Pair 1 ′ to Pair 4 ′. It is only for illustrative purpose. The skilled person in the art should understand the other pins comprised in HDMI transceiver circuit  210  and its purposes.  FIG. 6  is a diagram illustrating a switching unit  230  operating in the second connecting way according to an embodiment of the present invention. When the detecting pin CC detects the connection between the connector  300  and the receptacle  120  is in the second connecting way, according to the control signal CS sent by the signal converting circuit  220 , the switching unit  230  couples the pin Pair 4  of the video pin VSpin to the corresponding pin Pair 1  ‘ of the HDMI transceiver circuit  210  to transmit/receive the first part VS 1  of the video signal VS, couples the pin Pair 3  of the video pin VSpin to the corresponding pin Pair 2 ’ of the HDMI transceiver circuit  210  to transmit/receive the second part VS 2  of the video signal VS, couples the pin Pair 2  of the video pin VSpin to the corresponding pin Pair 3 ′ of the HDMI transceiver circuit  210  to transmit/receive the third part VS 3  of the video signal VS, and couples the pin Pair 1  of the video pin VSpin to the corresponding pin Pair 4 ′ of the HDMI transceiver circuit  210  to transmit/receive the fourth part VS 4  of the video signal VS. In an embodiment, the switching unit  230  utilizes switches to switch the connecting path between pins Pair 1 -Pair 4  to corresponding pins Pair 1 ′-Pair 4 ′. However, it is only for illustrative purpose, not a limitation of the present invention. In other words, the present invention does not limit the implement of the switching unit  230 . In addition, in an embodiment, the switching  230  is implemented outside the HDMI transceiver circuit  210  and the receptacle  120 , that is, the switching unit  230  can be solely implemented in an integrated circuit. In another embodiment, the switching unit  230  can be implemented in the HDMI transceiver circuit  210  or the receptacle  120 . It shall fall within the scope of the present invention as long as the circuit is capable of switching the connecting path between the pins Pair 1 -Pair  4  to the corresponding pins Pair 1  ‘-Pair 4 ’. 
         [0020]    Briefly summarized, the present invention discloses a USB type C—HDMI converter circuit. By converting a plurality of processing signals (e.g. DDC, HPD, 5 volts voltage signal) to a signal corresponding to USB 2.0 standard, the HDMI signal can be transmitted with another electronic device only via a USB type C interface cable, and also the electronic device can be charged at the same time due to the characteristic of USB type C interface cable. 
         [0021]    Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.