Abstract:
A dual-interface computer interface card includes a circuit board. The circuit board includes an ExpressCard connector, a USB connector, a control circuit, a converter, two USB signal traces, two DC traces. The two USB traces are electrically connected with the ExpressCard connector and the USB connector respectively. The two DC traces are electrically connected with the converter and respectively with the ExpressCard and USB connectors. The control circuit, subject to the required DC operation voltage, is optionally connected with one of the two DC traces, while another DC trace is connected with the converter to convert its DC voltage level into the DC voltage level required by the control circuit. Accordingly, the computer interface card can be connected with the computer system optionally by one of the connectors thereof for transmission of USB signals therebetween.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates generally to computer peripherals and more particularly, to a dual-interface computer interface card capable of hot plug. 
         [0003]    2. Description of the Related Art 
         [0004]    As the information technology (IT) advances by leaps and bounds, the cybernetic devices need to meet diverse requirements not only by basic built-in hardware but also by a variety of peripheral devices. Particularly, the portable devices which are compatible with most of the computer systems and capable of hot plug, like wireless communication apparatuses, e.g. wireless network or Bluetooth devices, or mass storage memory devices, can fulfill compactness, convenience, practicality, and diversification required by the IT products. In addition, the desktop and laptop computers and the personal digital assistants (PDA) are more and more popular, such that the suppliers of the computer peripherals are led to ceaseless development and breakthrough of the portable devices compatible with each computer system. 
         [0005]    Currently, universal serial bus (USB) is the mainstream connection technology of peripheral interface, and the peripherals having USB interface keep developed one by one. Even the Personal Computer Memory Card International Association (PCMCIA), which first developed PCMCIA interface, also developed and proposed a new ExpressCard interface in 2003, which is the combination of USB and PCI (peripheral component interconnection) Express for enhancing transmission velocity and bandwidth, attaining connection convenience, and reducing the system cost, thus having characteristics of broadband transmission of USB and high-efficiency operation of PCI Express. In addition, the USB 2.0 interface technology which is downward compatible with USB 1.1 and USB 1.0 is combined in the ExpressCard. Accordingly, the ExpressCard is compatible with the general notebook and desktop computers to become the high-speed serial bus interface. 
         [0006]    For the desktop computer, however, the ExpressCard fails to directly plug into the USB port exposed outside the general computer but has to employ particular card readers for connection with the USB host controller of the computer system. One kind of the employed ExpressCard readers is a portable card reader having USB interface to make the interface conversion between the ExpressCard and the USB port of the computer system. Another kind of the employed ExpressCard readers is a built-in card reader in the computer system which accesses the peripheral interface compatible with the ExpressCard. However, the former is an additional portable device of the card reader and the latter needs extra hardware space inside the computer system for installation of the card reader, such they both fail to be casually and effectively applied to the current computer system. In addition, the ExpressCard interface defines direct current (DC) power requirement of 1.5/3.3V, that is different from the 5V DC power of standard USB interface. Therefore, the USB control chip in the ExpressCard could only be particularly designed with 3.3V DC operation, and the general control chips compatible with the standard USB interface fail to be applied to the ExpressCard, thus narrowing the scope of the application of the ExpressCard. 
       SUMMARY OF THE INVENTION 
       [0007]    The primary objective of the present invention is to provide a dual-interface computer interface card, which is characterized in the dual interfaces of ExpressCard and USB compatible with various computer systems. 
         [0008]    The foregoing objective of the present invention is attained by the dual-interface computer interface card is composed of a housing and a circuit board mounted in the housing. 
         [0009]    The circuit board includes an ExpressCard connector, a USB connector, a control circuit, a converter, two USB signal traces, a first DC trace, and a second DC trace. The ExpressCard connector is provided for plugging into a built-in ExpressCard slot of a notebook or general computer. The USB connector is provided for plugging into a USB port of the general computer system. The two USB traces are coupled with each other and electrically connected with the ExpressCard connector and the USB connector respectively. The first DC trace is electrically connected with the ExpressCard connector and the converter for transmitting 3.3V DC power supplied by the notebook or general computers via the ExpressCard interface. The second DC trace is electrically connected with the USB connector and the converter for transmitting 5V DC power supplied by the USB interface of the general computer system. The control circuit includes a USB signal terminal and a power terminal. The USB signal terminal is electrically connected with the two USB signal traces. The power terminal is selectively connected with one of the two DC traces according to the required DC operation voltage of the control circuit, while another DC trace is connected with the converter to convert its DC voltage level into the DC operation voltage required by the control circuit. 
         [0010]    In light of the above, the ExpressCard connector is designed as the standard structure of ExpressCard interface for compatibility with the ExpressCard slot in the computer, while the USB connector can be designed in various portable structures of USB interface for connection with various computer systems respectively. Therefore, either of the connectors of the dual-interface computer interface card is selectively for transmission of USB signals with the computer system. In addition, the control circuit can be optionally adopted with various application of DC operation voltage. When the control circuit requires 3.3V for the DC operation voltage, the power terminal is electrically connected with the first DC trace and the converter functions as converting the voltage level (5V) of the second DC trace into the voltage level (3.3V) of the first DC trace. When the control circuit requires 5V for DC operation voltage, the power terminal is electrically connected with the second DC trace and the converter functions as converting the voltage level (3.3V) of the first DC trace into the voltage level (5V) of the second DC trace. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1A  is a schematic view of a first preferred embodiment of the present invention, illustrating the appearance of the connector of the ExpressCard interface. 
           [0012]      FIG. 1B  is another schematic view of the first preferred embodiment of the present invention, illustrating the appearance of the connector of the USB interface. 
           [0013]      FIG. 2  is another schematic view of the first preferred embodiment of the present invention, illustrating that the circuit board is mounted in the housing. 
           [0014]      FIG. 3  is a circuit diagram of the circuit board of the first preferred embodiment of the present invention. 
           [0015]      FIG. 4  is a circuit diagram of the control circuit of the first preferred embodiment of the present invention. 
           [0016]      FIG. 5  is a circuit diagram of the circuit board of a second preferred embodiment of the present invention. 
           [0017]      FIG. 6  is a circuit diagram of the circuit board of the second preferred embodiment of the present invention. 
           [0018]      FIG. 7  is a schematic view of a third preferred embodiment of the present invention, illustrating the appearance of the connector of the mini USB interface. 
           [0019]      FIG. 8  is a schematic view of a fourth preferred embodiment of the present invention, illustrating the appearance of the signal wires disposed on the circuit board. 
           [0020]      FIG. 9  is a schematic view of a fifth preferred embodiment of the present invention, illustrating the appearance of the USB terminal in connection with the USB plug. 
           [0021]      FIG. 10  is another schematic view of the fifth preferred embodiment of the present invention, illustrating the appearance of the USB plug. 
           [0022]      FIG. 11  is another schematic view of the fifth preferred embodiment of the present invention, illustrating that the USB plug is received in the slot of the housing. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0023]    Referring to  FIGS. 1-3 , a dual-interface computer interface card  1  constructed according to a first preferred embodiment of the present invention is composed of a housing  10  and a circuit board  20  mounted in the housing  10 . The circuit board  20  includes an ExpressCard connector  201 , a USB connector  202 , a converter  21 , a control circuit  22 , two USB signal traces  23  and  24 , a first DC trace  25 , and a second DC trace  26 . 
         [0024]    The ExpressCard connector  201  is a standard structure of ExpressCard interface for plugging into an ExpressCard slot of a notebook computer (not shown) or a general computer system (not shown). As shown in  FIG. 3 , the ExpressCard connector  201  has a USB signal terminal  201   a  (D+, D−) and a power terminal  201   b  (3.3V, GND) which are electrically connected with the USB signal trace  23  and the first DC trace  25  respectively. 
         [0025]    The USB connector  202  is a standard USB plug in this embodiment for plugging into a USB port (not shown) of the general computer system. As shown in  FIG. 3 , the USB connector  202  has a USB signal terminal  202   a  (D+, D−) and a power terminal  202   b  (5V, GND), which are electrically connected with the USB signal trace  24  and the second DC trace  26  respectively. 
         [0026]    The converter  21  includes a first DC terminal  211  and a second DC terminal  212 , which are electrically connected with the first and second DC traces  25  and  26  respectively. The converter  21  functions as converting the voltage level (5V) of the second DC trace  26  into the voltage level (3.3V) of the first DC trace  25 . In this embodiment, the converter  21  is a chip (No. XC6204) produced by TOREX SEMICONDUCTOR LTD. located in Japan. 
         [0027]    The control circuit  22  includes a USB signal terminal  22   a  (D+, D−) and a power terminal  22   b  (V+, GND), which are electrically connected with the two USB signal traces  23  and  24  and the first DC trace  25  respectively. Referring to  FIG. 4 , the control circuit  22  is combined with a Bluetooth control chip having USB interface to have an antenna  221 , a band pass filter  222 , a TX balun  223 , a USB Bluetooth control chip  224 , a memory  225 , and an LED indicator  226  electrically connected with the USB Bluetooth control chip  224 , all of which are electrically interconnected. In this embodiment, the USB Bluetooth control chip  224  is an IC chip (No. BlueCore4) which is produced by CSR located in U.K. and whose required DC operation voltage is 3.3V. The antenna  221  is designed as a chip antenna for being conveniently received in the housing  10 . Once received with driving voltage of 3.3V and USB signals, the control circuit  22  can provide the function of Bluetooth communication for the computer system. 
         [0028]    To sum it up, when the computer interface card  1  is used in the notebook computer, i.e. the ExpressCard connector  201  is plugged into the ExpressCard slot of the notebook computer, the control circuit  22  can receive DC power supply of 3.3V from the notebook computer via the ExpressCard slot, the ExpressCard connector  201 , and the first DC trace  25 . Meanwhile, the control circuit  22  can communicate with USB host controller (not shown) of the computer system via the USB signal trace  23 , the ExpressCard connector  201 , and the ExpressCard slot of the notebook computer, thus enabling data exchange which is carried by USB signals between the control circuit  22  and a central processing unit (CPU; not shown) of the computer system. When the computer interface card  1  is used in the general computer system, i.e. the USB connector  202  is plugged into the USB port of the computer system, the DC power voltage of 5V provided by the USB port is transmitted to the converter  21  through the USB connector  202  and the second DC trace  26  to be converted into 3.3V and then provided for the control circuit  22  via the first DC trace  25 . In the meantime, data exchange between the control circuit  22  and a central processing unit (CPU; not shown) of the computer system is carried by USB signals transmitted via the USB signal trace  24 , the USB connector  202 , and the USB port of the computer system. Accordingly, the computer interface card  1  can be broadly used in the general computer system having USB interface without additional card reader externally plugged in or internally built in the general computer system. 
         [0029]    Referring to  FIG. 5 , a dual-interface computer interface card  2  constructed according to a second preferred embodiment of the present invention is similar to the first embodiment but different in the DC power application and connection of a circuit board  30  which is comprised of a converter  31  and a control circuit  32 . The converter  31  functions as converting the voltage level (3.3V) of the first DC trace  25  into the voltage level (5V) of the second DC trace  26 . In this embodiment, the converter  31  is a chip (No. LM2621) produced by National Semiconductor Corporation located in U.S.A. 
         [0030]    The control circuit  32  also includes a USB signal terminal  32   a  (D+, D−) and a power terminal  32   b  (V+, GND) which are electrically connected with the two USB signal traces  23  and  24  and the second DC trace  26  respectively. Referring to  FIG. 6 , the control circuit  32  is combined with a mass storage IC having USB interface to have a flash memory  321 , an LED indicator  322 , and a USB flash driver  323 , all of which are electrically interconnected. The USB flash driver  323  is an IC chip (No.UT161), which is produced by USBest Technology Inc. located in Taiwan and whose required DC operation voltage is 5V. The power source (not shown) of the flash memory  321  is supplied from the USB flash driver  323  and converted by a built-in voltage converter (not shown) of the USB flash driver  323 . When driving voltage of 5V and USB signals are provided for the control circuit  32 , the control circuit  32  can function as a USB mass storage device for the computer system. 
         [0031]    In light of the above, when the computer interface card  2  is used in the notebook computer, i.e. the ExpressCard connector  201  is plugged into the ExpressCard slot of the notebook computer, the 3.3V DC power supplied by the ExpressCard slot is transmitted to the converter  31  through the ExpressCard connector  201  and the first DC trace  25  to be converted into 5V and then provided for the control circuit  32  via the second DC trace  26 . In the meantime, the control circuit  32  can communicate with USB host controller (not shown) of the notebook computer through the USB signal trace  23 , the ExpressCard connector  201 , and the ExpressCard slot of the notebook computer, thus enabling data exchange which is carried by USB signals between the control circuit  32  and the CPU of the notebook computer. When the computer interface card  2  is used in the general computer system, i.e. the USB connector  202  is plugged into the USB port of the computer system, the control circuit  32  can receive 5V DC power provided by the USB port via the USB connector  202  and the second DC trace  26 , and meanwhile, data exchange between the control circuit  32  and the CPU of the computer system is carried by USB signals transmitted through the USB signal trace  24 , the USB connector  202 , and the USB port of the computer system. Therefore, the computer interface card  2  can be widely applied to the general computer system having the USB interface without the additional card reader externally plugged in or internally built in the general computer system. 
         [0032]    It is to be noted that the computer interface card of the present invention is not externally structurally limited to the housing with the connectors. When the computer interface card plugs into the ExpressCard slot of the notebook computer, referring to  FIG. 1 , the USB connector  202  of the computer interface card looks very protrusive. In this respect, referring to  FIG. 7 , a dual-interface computer interface card  3  constructed according to a third preferred embodiment of the present invention is similar to the aforementioned embodiments but different in that the computer interface card  3  includes a mini USB socket  301  instead of the USB connector  202 , such that when the computer interface card  3  plugs into the ExpressCard slot of the notebook computer, the computer interface card  3  does not look protrusive all the time but only when the mini USB socket  301  is connected with the USB connection port of the computer system through a USB cable (not shown). 
         [0033]    Referring to  FIG. 8 , a dual-interface computer interface card  4  constructed according to a fourth preferred embodiment of the present invention is similar to the first embodiment but different in that the computer interface card  4  includes a wiring connector  401 , which is composed of USB interface (VSUB, GND, D+, D−) and is disposed on a circuit board  40 , instead of the USB connector  202  of the first embodiment. The wiring connector  401  electrically functions the same as the USB connector  202  does. Accordingly, the module engineering for the USB plug or slot can be eliminated from the computer interface card  4  and the circuit space utilization of the circuit board can be more efficient. 
         [0034]    Referring to  FIGS. 9-11 , a dual-interface computer interface card  5  constructed according to a fifth preferred embodiment of the present invention is similar to the first embodiment but different in that the computer interface card  5  includes a USB terminal  501 , which is composed of USB interface (VSUB, GND, D+, D−), instead of the USB connector  202  of the first embodiment and the circuit board  20  is mounted in a housing  50 . The USB terminal  501  is mounted on the circuit board  20  and is electrically connected with a USB plug  52  through a cable  51 . The cable  51  and the USB plug  52  are exposed outside the housing  50 . The housing  50  further includes a reception  502  for receiving the USB plug  52 . 
         [0035]    When the computer interface card  5  is used in the notebook computer in such a way that the ExpressCard connector  201  plugs into the ExpressCard slot of the notebook computer, the USB plug  52  can be received into the reception  502  of the housing  50 . When the computer interface card  5  is used in the general computer system, the USB plug  52  can be drawn out of the reception  502  and then inserted into the USB port of the computer system. Accordingly, the computer interface card  5  still has equivalent circuit function to those of the aforementioned embodiments and further considers the aesthetic appearance and safety, i.e. it prevents the USB plug  52  from exposure outside the housing  50  and damage incurred by accidental crash. 
         [0036]    Although the present invention has been described with respect to specific preferred embodiments thereof, it is no way limited to the details of the illustrated structures but changes and modifications may be made within the scope of the appended claims.