Abstract:
A dual interface SIM card adaptor is described for use with an existing SIM card slot that provides a dual interface electronic information storage card. The dual interface SIM card carrier comprises a flexible printed circuit board, a mini-sized SIM card, a housing to house the mini-sized SIM card, and a cap to affix the mini-sized SIM card in place. The mini-sized SIM card has dimensions that are less than the dimensions for a typical SIM card. The mini-sized SIM card is separable from a carrier that holds the mini-sized SIM card and an antenna. The adaptor is inserted into the SIM card slot in a mobile handset for contact electronic communication, such as wireless telecom, and for contactless electronic communication, such as public transportation, payment and RFID. Contactless communication can be carried out by RFID, Near Field Communication or bar codes.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Background of the Invention 
         [0002]    The present invention relates generally to electronic circuit cards, and more specifically to an adaptor for a dual interface electronic information storage card for contact and contactless communications. 
         [0003]    2. Description of Related Art 
         [0004]    The use of electronic information storage cards such as smart cards has grown rapidly in recent years as mobile devices have increasingly replaced heavier, larger difficult to carry notebook computers, in the lives of people in both industrial and developing countries. This trend is particularly poignant in developing countries like China and India where new infrastructures are built based on the latest technologies in wireless networks instead of on land line systems. The use of mobile handsets in these developing countries has therefore grown by leaps and bounds as the economic growth in these countries has outpaced industrial countries. 
         [0005]    Smart cards can be used in a wide range of applications including Subscriber Identification Modules (SIMs) for mobile phones, credit or ATM cards, high-security identification and access-control cards, authorization cards for pay television, public transport and public phone payment cards. SIM cards are widely deployed and used around the world, particularly in countries that run Global System for Mobile Communications (GSM) cellular networks. A SIM card is an integrated circuit card about the size of a postage stamp with embedded integrated circuits. The embedded integrated circuits of the SIM card store information that includes the identification of a mobile phone service subscriber, subscription information, preferences, saved telephone numbers, text messages and other type of information depending on the design. 
         [0006]    Two common types of smart cards exist on the market today, “contact” and “contactless” smart cards. The first type of smart card is referred to a “contact smart card” which has a small gold chip for making electrical contacts and another for reading information from the gold chip and for writing information onto the gold chip. The contact smart card has a set of contacts, dimensions and locations that are defined by International Organization Standardization (ISO) 7816-2. 
         [0007]    The second type of smart card is referred to as a “contactless smart card” where an integrated circuit chip communicates with a card reader, such as through Radio Frequency Identification (RFID) induction technology. A popular use of the contactless smart card is to process a transaction quickly that is preferably hands-free, such as for use on mass transit systems. The contactless smart card requires close proximity to an antenna. The standard for the contactless smart card communications is defined in ISO 14443. 
         [0008]    One problem that has arisen is the presence of blockage on a backside of a mobile handset when communicating between the mobile handset and a contactless reader or writer. A component placed on the backside of the mobile handset, such as a battery, could potentially cause interference during a contactless communication. Accordingly, there is a need to design a dual interface SIM card adaptor for conducting contact and contactless communications. 
       SUMMARY OF THE INVENTION 
       [0009]    The present invention describes a dual interface SIM card adaptor (or carrier) for use with an existing SIM card slot that provides a dual interface electronic information storage card. The dual interface SIM card carrier comprises a flexible printed circuit board, a mini-sized SIM card, a housing to house the mini-sized SIM card, and a cap to affix the mini-sized SIM card in place. The mini-sized SIM card has dimensions that are less than the dimensions for a typical SIM card. The mini-sized SIM card is separable from a carrier that holds the mini-sized SIM card and an antenna. The adaptor is inserted into the SIM card slot in a mobile handset for contact electronic communication, such as wireless telecom, and for contactless electronic communication, such as for use on public transportation, payment and Radio Frequency Identification (RFID). Contactless communication can be carried out by RFID, Near Field Communication (NFC) or bar codes. 
         [0010]    The mini-sized SIM card includes eight contact pads C 1  through C 8 , where the contact pads C 4  and C 8  are typically not used. In the present invention, the contact pads C 4  and C 8  are connected to the RF input pads on an integrated circuit chip so as to facilitate contactless communication. In one embodiment, the mini-sized dual interface SIM card has dimensions of about 15 mm in length, about 12 mm in width, and less than 1 mm thickness. In addition, the thickness of the dual interface SIM card carrier is less than 1 mm so that the dual interface SIM card carrier can be inserted in the SIM slot on a mobile handset. 
         [0011]    The flexible printed circuit board has a first principal surface that is used to reroute the contact pads of the mini-sized SIM card to the six connecting pins in the SIM slot. The six contact pads on the first principal surface of the flexible printed circuit board for SIM slot connections are denoted as C 1 -C 3  and C 5 -C 7 . The flexible printed circuit board has a second principle surface that has eight contact pads, with the addition of contact pads C 4  and C 8  to the six contact pads, C 1 -C 3  and C 5 -C 7 . The contact pads C 4  and C 8  on the second principal surface of the mini-sized SIM card are used for connecting to the antenna. The flexible printed circuit board has a pair of wires, which connect to the contact pads C 4  and C 8 , for connecting to a connector of an antenna for contactless communication. 
         [0012]    The antenna includes a connector that is detachable from the pair of wires from the flexible printed circuit board. Embodiments of the antenna can be manufactured by a wide variety of methods including etched metal lines on a printed circuit board, a wiring coil, or printing conducting wires onto a plastic paper. 
         [0013]    Broadly stated, a dual interface card carrier comprises a circuit board having first and second principal surfaces, the first principal surface having a plurality of contacts operating as a first interface for contact communication, the second principal surface having a second plurality of contacts operating as a second interface for contactless communication; a chip card having an inwardly-facing surface with a plurality of contact pads for making electrical contacts with the second plurality of contacts in the second principal surfaces; and a chip housing that houses the chip card. 
         [0014]    Advantageously, the present invention describes a dual interface SIM card carrier that prevents a blockage, such as a battery attached on the backside of the handset, for placement between a dual interface card and a contactless reader/writer during contactless communication. 
         [0015]    The structures and methods of the present invention are disclosed in the detailed description below. This summary does not purport to define the invention. The invention is defined by the claims. These and other embodiments, features, aspects, and advantages of the technology can be understood with regard to the following description, appended claims and accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]    The invention will be described with respect to specific embodiments thereof, and reference will be made to the drawings, in which: 
           [0017]      FIG. 1A  illustrates a perspective view from the bottom of a dual interface SIM card carrier with various components including a chip card having first size dimensions in accordance with the present invention. 
           [0018]      FIG. 1B  illustrates a perspective view from the top of a dual interface SIM card carrier with various components including the chip card having first size dimensions in accordance with the present invention. 
           [0019]      FIG. 2A  illustrates top views of stacking the various components in the dual interface SIM card carrier where the dual interface SIM card carrier includes the circuit board, the chip card and the cap in accordance with the present invention. 
           [0020]      FIG. 2B  illustrates bottom views of stacking the various components in the dual interface SIM card carrier where the dual interface SIM card carrier includes the circuit board, the chip card and the cap in accordance with the present invention. 
           [0021]      FIG. 3  illustrates the installation of the dual interface SIM card carrier and accessories into a mobile handset in accordance with the present invention. 
           [0022]      FIG. 4  illustrates an alternative embodiment of the dual interface SIM card carrier with a liftable cap in accordance with the present invention. 
           [0023]      FIG. 5  illustrates a perspective view of the chip card which is fitted into the chip housing for insertion into the SIM card slot in the mobile handset in accordance with the present invention. 
           [0024]      FIG. 6  illustrates an alternative embodiment for connecting the antenna to a chip card via contact pads A 1  and A 2  in accordance with the present invention. 
           [0025]      FIG. 7  is a graphical diagram illustrating one embodiment of sample dimensions of the chip card in accordance with the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0026]    A description of structural embodiments and methods of the present invention is provided with reference to  FIGS. 1-5 . It is to be understood that there is no intention of limiting the invention to the specifically disclosed embodiments but that the invention may be practiced using other features, elements, methods and embodiments. Like elements in various embodiments are commonly referred to with like reference numerals. 
         [0027]      FIGS. 1A-1B  illustrate perspective views from the bottom (or bottom views) and perspective views from the top (or top views), respectively, of various components in a dual interface SIM card carrier  10  that includes a chip card  20  having first size dimensions. The dual interface SIM card carrier  10  comprises a circuit board  30 , such as a flexible printed circuit board, a housing or chip housing  40  for housing the chip card  10 , and a cap  50  that fits over the housing  40  to hold the chip card  20  in a stable position. An exemplary example of the chip card  20  having the first size is a mini-sized dual interface Subscriber Identity Module (SIM) card. 
         [0028]    A typical SIM card slot  62  is capable of holding a typical SIM card, which has second size dimensions with a plug-in size of about 25 mm long and 15 mm wide, and less than 1 mm thick. The carrier  10  has a plug-in SIM card size, for example less than 1 mm thick, for insertion into the SIM card slot  62  of a mobile handset  60 , as shown in  FIG. 3 . The chip card  20 , such as the mini-sized dual interface SIM card, has first size dimensions that are less than second size dimensions of the typical SIM card. The term “mini-sized” dual interface SIM card refers to the relatively smaller size dimensions of the chip card  20  compared to the typical SIM card. Embodiments of the chip card  20  include first size dimensions of 15 mm long, 12 mm wide, and less than 1 mm thick. 
         [0029]    The circuit board  30  has a first principal surface  31  from the bottom view and a second principal surface  32  from the top view. The first principal surface  31  of the circuit board  30  includes six contact pads  81 ,  82 ,  83 ,  85 ,  86 ,  87  for making connections in the SIM card slot  62 . The six contact pads on the first principal surface of the circuit board  30  correspond to contact pads C 1 -C 3  and C 5 -C 7  on the chip card  20  for making electrical connections. The second principal surface  32  of the circuit board  30  includes eight contact pads,  81 ,  82 ,  83 ,  84 ,  85 ,  86 ,  87 ,  88 , with the addition of contact pads C 4  and C 8  from the six contact pads, C 1 -C 3  and C 5 -C 7 . The contact pads C 4  and C 8  on the second principal surface of the chip card  20  are used for connecting to a connector or port of an antenna  74 , as shown in  FIG. 3 . The circuit board  30  further includes a pair of routing wires (C 4  and C 8 )  33 ,  34  that are sufficiently long to bypass a blockage, such as a battery on the back side of the handset, and are connected to the antenna  74  for contactless communication. 
         [0030]    The chip housing  40  has a first slot  41  for holding the chip card  20  and a second slot  42  for routing wires through the chip housing. The first slot  41  is provided for placing the chip card  20  in the chip housing  40 . A corner  23  of the first slot  41  is cut at an angle to ensure correct orientation when the chip card  20  is placed in the first slot  41 . The chip card  20  can be inserted in the first slot  41  with the angled corner  23  with the correct orientation. 
         [0031]    The chip card  20  has an inwardly-facing surface  21  with a plurality of contact pads  1 - 8  (C 1 -C 8 ) and an outwardly-facing surface  22 . The inwardly-facing surface  21  of the chip card  20  includes eight contact pads, C 1  through C 8 . The eight contact pads C 1  through C 8  are specified and defined in accordance with a smart card standard of the ISO 7816-2. The following table contains the contact pads definition according to ISO 7816-2. 
         [0000]    
       
         
               
               
               
             
           
               
                 TABLE 1 
               
               
                   
               
               
                 Contact Pad 
                 Designation 
                 Description 
               
               
                   
               
             
             
               
                 C1 
                 Vcc 
                 Power connection 
               
               
                 C2 
                 RST 
                 Reset line 
               
               
                 C3 
                 CLK 
                 Clock signal line 
               
               
                 C4 
                 RFU 
                 Reserved for future use 
               
               
                 C5 
                 GND 
                 Ground line 
               
               
                 C6 
                 Vpp 
                 Programming power connection 
               
               
                 C7 
                 I/O 
                 Input/output line that provides a 
               
               
                   
                   
                 half-duplex communication channel between 
               
               
                   
                   
                 the reader and the smart card 
               
               
                 C8 
                 RFU 
                 Reserved for future use 
               
               
                   
               
             
          
         
       
     
         [0032]    The contact pads C 1 , C 2 , C 3 , C 8 , C 6 , C 7  have been assigned as interface pins for use with the functions as described in Table 1. Two of the contact pads, C 4  and C 8 , are listed as reserved for future use. In the present invention, the contact pads C 4  and C 8  are used as RF input pads of the chip card  20 , which is an integrated circuit chip. The contact pads C 4  and C 8  are connected to the antenna  74 , as shown in  FIG. 3 , thereby providing contactless communication such as publication transportation, mobile payment, RFID and other types of contactless communication. 
         [0033]    The cap  50  includes a corner  51  that is cut at an angle for matching correct orientation with a corner of the chip housing  40  that is also cut when placing the cap over the chip housing  40 . The chip card  20  can be inserted in the first slot  41  with the angled corner  23  in the correct orientation. The cap  19  includes a through-hole  19  for passing a wire through the cap  50 . The cap  50  further includes a through hole  52  for passing through the pair of wires  33 ,  34  through the cap  50 . 
         [0034]      FIG. 2A  illustrates top views of stacking the various components in the dual interface SIM card carrier  10  where the dual interface SIM card carrier  20  includes the chip card  20 , the circuit board  30 , the chip housing  40  and the cap  50 . Each of the components, the circuit board  30 , the chip housing  40 , the chip card  20 , and the cap  50  are shown with the surfaces and dimensions as viewed from the top. The top view of the circuit board  30  shows the second principal surface  32  with eight contact pads,  81 ,  82 ,  83 ,  84 ,  85 ,  86 ,  87 ,  88 . The top view of the chip housing  40  shows the first slot  41  and the chip housing disposed over the circuit board  30 . The chip card  20  is placed in the first slot  41  of the chip housing  40  with correct orientation by matching the angled corner  23  of the chip card with the angled corner  43  of the chip housing. The cap has ledges  53 ,  54  that are placed over the side surfaces of the chip housing  40  to securely hold the chip card  20  in the housing  40 . The cap  50  also has the angled corner  51  that matches with the angled corner  43  of the housing  40  to ensure correct orientation. 
         [0035]      FIG. 2B  illustrates bottom views of stacking the various components in the dual interface SIM card carrier  10  where the dual interface SIM card carrier  10  includes the chip card, the circuit board  30 , the chip card  40  and the cap  50 . Each of the components, the circuit board  30 , the chip housing  40 , the chip card  20 , and the cap  50  are shown with the surfaces and dimensions as viewed from the bottom. When viewing from the bottom, the first component encountered is the circuit board  30 , the second component encountered is the chip housing  40 , the third component encountered is the chip card  20 , and the fourth component encountered is the cap  50 . The bottom view of the circuit board  30  shows the first principal surface  31  with six contact pads,  81 ,  82 ,  83 ,  85 ,  86 ,  87 . The bottom view of the chip housing  40  shows the first slot  41  and the chip housing disposed over the circuit board  30 . The chip card  20  is placed in the first slot  41  of the chip housing  40  with correct orientation by matching the angled corner  23  of the chip housing  40  with the angled corner  43  of the chip housing. The cap has ledges  53 ,  54  that are placed over the side surfaces of the chip housing  40  to securely hold the chip card  20  in the housing  40 . The cap also has the angled corner  51  that matches with the angled corner  43  of the housing  40  to ensure correct orientation. 
         [0036]      FIG. 3  illustrates the installation of the dual interface SIM card carrier and accessories into a mobile handset  60 . The mobile handset  60  includes the SIM card slot  62  with dimensions suitable for placement of a typical SIM card. The mobile handset  60  as used herein includes, but is not limited to, cell phones, personal digital assistants (PDA), mobile music players, and other types of mobile devices. The first principal surface  31  of the circuit board  30  has six pins facing the SIM card slot  62  and making electrical contacts in the SIM card slot  62 . The second principal surface  32  of the circuit board  30  has eight pins facing the chip card  20  and making electrical contacts with the eight contact pads, C 1 -C 8 , of the chip card  20 . The circuit board  30  and the chip housing  40  are inserted into the SIM card slot  62  of the mobile handset  60 . The chip card  20  is inserted into the first slot  41  of the housing  40 . The cap  50  is disposed over the chip housing  40  to hold the chip card  20  securely. A battery  70  is placed over the cap  50  and into the mobile handset  60 . The antenna  74  is attached to a back surface  71  of the battery  70 . 
         [0037]    The antenna  74  includes a connector  75  for connecting to the pair of routing wires  33 ,  34  extending from the circuit board  30 . The pair of routing wires  33 ,  34  are also referred to as an extended tail that is sufficiently long to extend in a circuitous manner as to bypass the blockage, such as the battery  72 , on the back side of the mobile handset  60 . The antenna  74  is detachable from the extended tail or the pair of wires  33 ,  34  that is extended from the circuit board  30 . Manufacture of the antenna  74  can be carried out using a wide variety of techniques, including etched metal lines on a printed circuit board or a wiring coil, or printing conducting wires on plastic paper. A cover  76  is placed over the antenna  74  and fitted into an open area  75  in the back of the mobile handset  60 . 
         [0038]      FIG. 4  illustrates an alternative embodiment of a dual interface SIM card carrier  90  with a liftable cap  91 . The dual interface SIM card carrier  90  includes a chip housing  92  that is attached to the liftable cap  91 . The liftable cap  91  allows the chip card  20  to be placed in a slot  93  of the chip housing  82 . The liftable cap  91  has a surface  94  with a through hole  95  for passing through the pair of wires  33 ,  34 . 
         [0039]      FIG. 5  illustrates a perspective view of the chip card  20  which is fitted into the chip housing  40  for insertion into the SIM card slot  62  in the mobile handset  60 . The chip card  20  comprises a mini-sized SIM card that is relatively smaller in size than a regular SIM card. The chip card  20  includes three dimensional values, a first dimensional value L of about 15 mm, a second dimensional value W of about 12 mm, and a third dimensional value T of less than 1 mm. These dimensional values are intended as one embodiment of the present invention. Other dimensions of greater than or less than each of the three dimensional values L, W, and T can be practiced without departing from the spirit of the present invention. 
         [0040]      FIG. 6  illustrates an alternative embodiment for connecting the antenna  74  to a chip card  100  via contact pads A 1  and A 2 . Embodiments of the chip card  20  can have configurations as shown in the chip card  20  in  FIG. 5  or in the chip card  100  in  FIG. 6 , which are applicable to  FIGS. 1 through 4 . The additional contact pads A 1   102  and A 2   104  provides two connecting sources on the chip card  100  for connecting to the antenna  74  through the pair of wires  33 ,  34 . Each of the contact pads A 1   102  and A 2   104  has a triangular roof top formed by lines  105 ,  106 , and formed by lines  107 ,  108 , respectively. The line  105  of the contact pad A 1   102  is an uninterrupted line, unlike a conventional SIM card that has a gap  109  along the line  105 . Therefore, the contact pad A 1   102  forms a first geometric shape with uninterrupted lines on the inwardly-facing surface  21  of the chip card  20 . Similarly, the line  108  of the contact pad A 2   104  is an uninterrupted line, unlike a conventional SIM card that has a gap  110  along the line  108 . Therefore, the contact pad A 2   104  forms a second geometric shape with uninterrupted lines the inwardly-facing surface  21  of the chip card  20 . The first and second geometric shapes can be designed with a wide variety of shapes. In this embodiment, the first and second geometric shapes resemble a rotated house with a large triangular roof top with short sides. 
         [0041]      FIG. 7  illustrates one embodiment of a graphical diagram  110  showing sample dimensions of the chip card  20  or  100 . The size of the chip card  20  or  100  as show in the graphical diagram  110  includes a length L of about 15 mm and a width W of about 12 mm. Measurements of the contact pads are also illustrated in  FIG. 7 . The distance between side walls of the chip card  20  or  100  from a left edge  112  and an upper edge  114  are also shown. These parameters provide a set of exemplary sizes of the chip card  20  or  100 . Other variations and modifications from the suggested dimensions can be practiced without departing from the spirits of the present invention. 
         [0042]    The invention has been described with reference to specific exemplary embodiments. Various modifications, adaptations, and changes may be made without departing from the spirit and scope of the invention. Accordingly, the specification and drawings are to be regarded as illustrative of the principles of this invention rather than restrictive, the invention is defined by the following appended claims.