Patent Document

BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The invention relates in general to a memory card, wherein the memory card is integrated with a communication serial interface and a standard card interface; wherein the memory card can be used for a device that is compatible to the standard card interface or used for a device that is compatible to the communication serial interface; wherein a shape, a size and a electrical contacts of the memory card are compatible to a specification of a present standard memory card. 
         [0003]    2. Description of the Related Art 
         [0004]    With the rapid development of technology, many electrical devices and portable devices are designed to provide more and more functions to facilitate users to use. For example conventional memory cards such as CF™ card or SD Memory Card provide more storage spaces and faster storage speed than before. Moreover, Secure Digital Association (SDA) further provides Mini-SD™ Card and Micro-SD™ Card with much smaller size, so as to reduce the size and also to facilitate users to carry. 
         [0005]    However, there are plenty of interfaces with different specifications of electronic devices in the market. For example, the USB interface is popularly used for computers and peripherals in recent years. In addition, conventional portable storage devices for a digital camera or MP3 can be of various different kinds of memory cards. Hence an adapting device is required to transmit data. Therefore a dual interface memory card is brought to the market, which provides the memory card with the standard interface and a second interface to facilitate users to use. 
         [0006]    With reference to  FIG. 5 , a perspective view of a conventional standard SD memory card is shown. A body  80  includes a plurality of electrical contacts  81  on one side. The electrical contacts  81  form a memory card standard interface  82  for the memory card to be used for a card reader with a compatible interface. 
         [0007]    With reference to  FIG. 6 , a circuit block diagram of the conventional standard memory card shows functionality of a standard SD memory card. The body  80  as shown in  FIG. 5  includes at least a memory card control circuit  83  and a memory module  84 . The memory card control circuit  83  is connected with a card reader device having a compatible interface through the memory card standard interface  82 . 
         [0008]    With reference to  FIG. 7 , a conventional dual interface SD memory card mainly includes a housing  91  and a cap  92 . The cap  92  is combined with the housing  91  to form a standard size of a SD memory card. The dual interface memory card includes a memory card standard interface  93  and a communication serial interface  94  at two ends of the housing  91  respectively. The memory card standard interface  93  allows the dual interface memory card to be used for a card reader with the compatible interface. The communication serial interface  94  can be connected to an USB port of electronic devices. 
         [0009]    With reference to  FIG. 8 , an block circuit diagram of the conventional dual interface memory card includes a memory card control circuit  71 , a reader control circuit  72 , a logic control circuit  73  and a memory module  74  inside the hosing  91  as shown in  FIG. 7 . The memory card control circuit  71 , the reader control circuit  72  and the logic control circuit  73  can be further integrated as a dual interface control circuit  70 . The memory card control circuit  71  is connected to the memory card standard interface  93  through the logic control circuit  73 . The reader control circuit  72  and the memory card control circuit  71  are coupled together via the logic control circuit  73  for storing data of the memory module  74 . The reader control circuit  72  makes the dual interface memory card able to be directly used for an USB interface or for an IEEE 1394 interface of electronic devices with the communication serial interface  94 . The communication serial interface  94  shown in the diagram is an USB interface. 
         [0010]    The aforesaid conventional dual interface memory card can be used for the memory standard interface or the communication serial interface. However, the cap  92  and the electrical contacts of the communication serial interface  94  are not of the standard specification defined in the Secure Digital Association. Furthermore, mechanical structure designs of the reader devices of different brands are different. Therefore a mechanical structure compatible problem still needs to be improved. 
       SUMMARY OF THE INVENTION 
       [0011]    The present invention provides a memory card integrated with a communication serial interface and a standard card interface. The memory card can be used for a device that is compatible to the standard card interface or the communication serial interface. A shape, a size and electrical contacts of the memory card are compatible to a specification of a standard memory card. 
         [0012]    The memory card includes a body and a communication serial interface. 
         [0013]    The body with a shape and size compatible to a standard memory card has electrical contacts as the memory card standard interface that allows the memory card to be used by devices that support the memory card standard interface. 
         [0014]    The communication serial interface is formed inside the body for the memory card to be used to electrical devices that support the communication serial interface. The memory card standard interface and the communication serial interface shares the same electrical contacts of the memory card body. 
         [0015]    The memory card of the present invention uses the communication serial interface and its own memory card standard interface, so as to provide more flexibility and convenience than before for users to choose the memory card standard interface or the communication serial interface to be coupled to an electronic device. Most importantly, the communication serial interface and the memory card standard interface share the same electrical contacts without changing the electrical contacts of the conventional specification of the memory card. With this design feature, the memory card of the present invention not only can be used for conventional reader devices that support the communication serial interface and the memory card standard interface, but also can be compatible to the future reader devices that the single electrical contact supports both the communication serial interface and the memory card standard interface. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]      FIG. 1  is a perspective view of a first preferred embodiment of the present invention. 
           [0017]      FIG. 2  is a circuit block diagram of the first preferred embodiment of the present invention. 
           [0018]      FIG. 3A  to  FIG. 3D  are detailed circuit diagrams of the first preferred embodiment of the present invention. 
           [0019]      FIG. 4  is a circuit block diagram of the second preferred embodiment of the present invention. 
           [0020]      FIG. 5  is a perspective view of a conventional standard memory card. 
           [0021]      FIG. 6  is a circuit block diagram of a conventional standard memory card. 
           [0022]      FIG. 7  is a perspective exploded view of a conventional dual interface memory card with a cap opened. 
           [0023]      FIG. 8  is a circuit block diagram of a conventional dual interface memory card. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0024]    With reference to  FIG. 1  and  FIG. 2 , a first preferred embodiment of the present invention includes a memory card body  10  and a circuit board inside the body  10 . The shape and the size of the memory card body  10  are of the same specification as a standard memory card. The circuit board includes at least a dual interface control circuit  20 , a memory module  30 , a switch circuit  12  and a power control circuit  13 . One end of the circuit is configured with multiple electrical contacts  11 . 
         [0025]    In this preferred embodiment of the present invention, the dual interface control circuit  20  is made up by a memory card control circuit  21 , a communication serial interface control circuit  22  and a logic control circuit  23 . The memory card control circuit  21  and the communication serial interface control circuit  22  are respectively coupled to the memory module  30  and an oscillator  14 . Moreover, the memory card control circuit  21  and the communication serial interface control circuit  22  are both coupled to the logic control unit  23 . The dual interface control circuit  20  further has a memory card standard interface  24  and a communication serial interface  25  respectively provided from the memory card control circuit  21  and the communication serial interface control circuit  22 . 
         [0026]    Further, the electrical contacts  11  form a communication port of the memory card. The communication port accomplishes an integration of the memory card standard interface  24  and the communication serial interface  25 . The foregoing integration of the communication port means that the memory card standard interface  24  and the communication serial interface  25  share the same electrical contacts  11 . A feasible technology is to make the switch circuit  12  switch the memory card standard interface  24  and the communication serial interface  25 , so as to make the electrical contacts  11  switch from external connection signals to a respective control circuit of the dual interface control circuit  20 . Moreover, a design of the switch circuit  12  can further comprises static electricity protection for the memory card. 
         [0027]    Power for the memory card standard interface  24  and the communication serial interface  25  are common coupled to the same electrical contacts  11  via the switch circuit  12  and the power control circuit  13 . The power control circuit  13  not only provides the power to the dual interface control circuit  20  and the memory module  30 , but also depends on a predetermined voltage detection and definition range to control the switch circuit  12  to determine which control circuit of the dual interface control circuit  20  that the shared electrical contacts  11  will be coupled with. 
         [0028]    With reference to  FIG. 3A  to  FIG. 3D , the first preferred embodiment of the present invention includes the dual interface control circuit  20 , the memory module  30 , the electrical contacts  11 , the switch circuit  12 , the power control circuit  13  and the oscillator  14 . 
         [0029]    The memory card standard interface  24  that the dual interface control circuit  20  supports is of SD memory card standard interface having corresponding signal pins of SD 0  to SD 3 , SDCLK, SDCMD, and the like. The communication serial interface  25  that the dual interface control circuit  20  supports is of an USB interface having corresponding signal pins of DP and DM. The dual interface control circuit  20  is coupled to the memory module  30  by multiple pins. 
         [0030]    Further, the pins of SD 0  to SD 3  of the memory card standard interface  24  are coupled to the electrical contacts  11 , and the pins SDCLK and SDCMD are coupled to the switch circuit  12 . 
         [0031]    The pins of DP and DM of the communication serial interface  25  are coupled to the switch circuit  12 . The power pins VCC 33  of the dual interface control circuit  20  and the memory module  30  are coupled to power contacts VDD of the electrical contacts  11  via the power control circuit  13 . 
         [0032]    A power terminal VCC of the switch circuit  12  is coupled to the power contacts VDD of the electrical contacts  11 . 
         [0033]    The power control circuit  13  includes an electrical switch circuit, a voltage regulator circuit U 3  and a voltage detection circuit U 4 . In this preferred embodiment, the electrical switch circuit is a field effect transistor (FET) Q 1  having a source and a drain respectively coupled to the power contact VDD of the electrical contacts  11  and the power pin VCC 33  of the memory card standard interface  24 . A gate of the field effect transistor Q 1  is coupled to the voltage detection circuit U 4 . An input terminal of the voltage detection circuit U 4  is coupled to the power contact VDD, and an output terminal of the voltage detection circuit U 4  is coupled to a control pin USB_ACTV of the dual interface control circuit  20 . Moreover, an input terminal and an output terminal of the voltage regulator circuit U 3  are respectively coupled to the power contact VDD of the electrical contacts  11  and the power pin VCC 33  of the dual interface control circuit  20  and the memory module  30 . 
         [0034]    Operations of the aforesaid circuit are as follows. 
         [0035]    A standard operating voltage of the SD memory standard interface is defined as 3.3 volts, and a standard operating voltage of the USB interface is defined as 5 volts. When the memory card of the present invention is plugged in an electronic device that supports the SD memory card, the electronic device provides power to the memory card. The power control circuit  13  of the memory card can detect that the power voltage of the electronic device is 3.3 volts with the power detection circuit U 4 . Then a corresponding control signal S, such as a low voltage level signal or a logic zero is generated. The control signal S will be sent to a pin  1  of the switch circuit  12  and the gate of the field effect transistor Q 1  of the power control circuit  13 . At this moment, the switch circuit  12  makes C 0  and C 1  of the electrical contacts  11  coupled to the pins SDCLK and SDCMD of the memory card standard interface  24  of the dual interface control circuit  20 . The control signal S of the power control circuit  13  makes the field effect transistor Q 1  conductive with a resistor R 5 , so as to make the power contacts VCC 33  and VDD electrically connected to be 3.3 volts. Hence the dual interface control circuit  20  and the memory module  30  can operate with normal voltage supply. 
         [0036]    On the other hand, when the memory card of the present invention is plugged in an interface connector of an electronic device that supports the USB interface, VDD is 5 volts. The control signal S output from the power detection circuit U 4  of the power control circuit  13  changes to a high electric potential or a logic one. The switch circuit  12  then makes C 0  and C 1  of the electrical contacts  11  coupled to the pins DP and DM of the communication serial interface  25  of the dual interface control circuit  20 . Then control signal S also turns off the field effect transistor Q 1  of the power control circuit  13 . The VDD with 5 volts voltage is then coupled to the power contact VCC 33  via the voltage regulator circuit U 3 . The power contact VCC 33  still acquires 3.3 volts to make the dual interface control circuit  20  and the memory module  30  operate with normal voltage supply. 
         [0037]    Further, the control signal S generated by the power control circuit  13  can be coupled to the dual interface control circuit  20  to make the dual interface control circuit  20  control peripheral signal flow. The signal flow includes the control signal of the switch circuit  12 . 
         [0038]    With reference to  FIG. 4 , the memory card of the present invention can further integrate the dual interface control circuit  20 , the switch circuit  12  or the power control circuit  13  as an integration control module  40 . When the memory card of the present invention is plugged to the electronic device, the power control circuit  13  can directly or indirectly control the switch circuit  12 . The integration control module  40  is of a new design circuit module controlled by an interface drive circuit  41 . An operating mode of the electrical contacts  11  of the memory card is then defined in a powered state that is when the integration control module  40  and the electronic device are in a handshake state. 
         [0039]    When the memory card of the present invention is plugged to the electronic device which supports the USB interface, an USB interface specification is defined as follows: when an electronic device is coupled to a product such as a memory card of the present invention, the electronic device detects the product and then makes the voltage level of pins DP and DM of the communication serial interface of USB to a low level for 10 milliseconds. 
         [0040]    When the memory card of the present invention is plugged to the electronic device which supports the SD memory card standard interface, an SD memory card standard interface specification is defined as follows: when an electronic device detects a product such as a memory card of the present invention, the electronic device should wait for a response of the product with a poll interval for 50 milliseconds after electrical contacts send out a clock signal CLK and also the electrical contacts send out an instruction CMD. 
         [0041]    The integration control module  40  can make the communication port compatible to the interface that the plugged device supports in the device handshake status according to the USB interface specification and the memory card standard interface specification. The design of the present invention also can be used for a low voltage USB device. 
         [0042]    It can be clearly understood from the above description that the present invention provides a memory card having the communication serial interface integrated with the standard card interface. The memory card can be used for the device that is compatible to the standard card interface of the memory card or used for the device that is compatible to the communication serial interface. The shape, size and the electrical contacts are also compatible to the specification of a conventional memory card. Therefore the integrated communication serial interface memory card includes more additional values and features of good utility than the conventional standard memory card, which provides better mechanical compatibility than the conventional dual interface memory card. 
         [0043]    The memory card can be CF™ card, SD Memory Card, miniSD™ Card, microSD™ Card, MMC Card, MMCplus™ Card, MMCmobile™ Card, MMCmicro™ Card, Memory Stick, Memory Stick PRO, Memory Stick Duo, Memory Stick PRO Duo, Memory Stick Micro, xD-Picture Cards™ or T-Flash. 
         [0044]    While the invention has been described by way of example and in terms of a preferred embodiment, it is to be understood that the invention is not limited thereto. On the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures.

Technology Category: g