Abstract:
An embodiment of this invention provides a system and method for indicating the orientation of a packaged IC in a socket. An LED is physically mounted to a socket. One lead of the LED is electrically connected to a positive voltage through a socket hole on the socket. When the orientation of the IC package in the socket is correct, the other lead of the LED is connected to a ground path on the packaged IC. As a result, the LED is activated indicating the orientation of the packaged IC is correct.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application is a divisional of application Ser. No. 10/420,577 also entitled, “A Method and System for Sensing IC Package Orientation in Sockets,” filed on Apr. 21, 2003 hereby incorporated herein by reference. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    This invention relates generally to packaged integrated electronic circuits. More particularly, this invention relates to sensing the orientation of a packaged IC in a socket.  
         BACKGROUND OF THE INVENTION  
         [0003]    Very Large Scale Integrated (VLSI) chips may contain millions of transistors and electrical connections. Because VLSI chips may be so complex, a great deal of testing may be required to verify that a particular chip is fully functional. The time required to test an integrated circuit (IC) may increase the cost of an IC. As a result, it is desirable to reduce the time required to test an IC.  
           [0004]    ICs are typically manufactured on a silicon wafer. Each silicon wafer may contain dozens of individual ICs. These ICs may be microprocessors, DRAMs (Dynamic Random Access Memory), SRAMs (Static Random Access Memory), or other types of ICs. The individual ICs on a silicon wafer are usually tested before the wafer is cut into separate, individual ICs. After all the ICs on the wafer are tested, the wafer is cut into separate, individual ICs and the ICs that passed the tests during wafer test are packaged.  
           [0005]    Next, packaged ICs are tested. Packaged ICs are usually placed in a socket that is connected to external test equipment. The external test equipment applies power and signals to operate and test packaged ICs. The tests applied by test equipment can be very complex and as a result may require a relatively great deal of time to complete testing. Before applying the complete suite of tests found on external test equipment, it would be helpful to know if the packaged IC is correctly oriented in a test socket.  
           [0006]    The orientation of a packaged IC may be difficult to detect, for example, because the module may be symmetrical about both the X and Y axis. As a result the packaged IC may be incorrectly placed in a socket. If a packaged IC is incorrectly placed in a socket during testing of the packaged IC, the tests may fail and a great deal of time and effort may be used before it is discovered the packaged IC is incorrectly oriented in the socket.  
           [0007]    In addition, when a packaged IC is incorrectly oriented in a socket that is part of a system, for example, a computer, the system may not operate properly. Again, a great deal of time and effort may be used in this situation before the incorrect orientation is detected.  
           [0008]    There is a need in the art to communicate the orientation of a packaged IC in a socket. One embodiment of this invention communicates the orientation of a packaged IC in a socket by activating an LED mounted to the socket when the orientation of the packaged IC is incorrect. A detailed description of this embodiment of this invention is described later.  
         SUMMARY OF THE INVENTION  
         [0009]    An embodiment of this invention provides a system and method for indicating the orientation of a packaged IC in a socket. An LED is physically mounted to a socket. One lead of the LED is electrically connected to a positive voltage through a socket hole on the socket. When the orientation of the IC package in the socket is correct, the other lead of the LED is connected to a ground path on the packaged IC. As a result, the LED is activated indicating the orientation of the packaged IC is correct.  
           [0010]    Other aspects and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawing, illustrating by way of example the principles of the invention. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]    [0011]FIG. 1 is a mechanical drawing of a socket and light source viewed from the top.  
         [0012]    [0012]FIG. 2 is a mechanical drawing of a socket, a light source, and a packaged IC viewed from the side.  
         [0013]    [0013]FIG. 3 is a mechanical drawing of a socket, a light source, and a packaged IC viewed from the top.  
         [0014]    [0014]FIG. 4 is a mechanical drawing of a socket, a light source, and a packaged IC viewed from the top.  
         [0015]    [0015]FIG. 5 is a mechanical drawing of a socket, a light source, and a packaged IC viewed from the top.  
         [0016]    [0016]FIG. 6 is a mechanical drawing of a socket, a light source, and a packaged IC viewed from the top.  
         [0017]    [0017]FIG. 7 is a mechanical drawing of a socket, an audio source, and a packaged IC viewed from the side.  
         [0018]    [0018]FIG. 8 is a mechanical drawing of a socket, a resistor, and a packaged IC viewed from the side.  
         [0019]    [0019]FIG. 9 is a mechanical drawing of a socket, a light source, and a packaged IC viewed from the top.  
         [0020]    [0020]FIG. 10 is a mechanical drawing of a socket, a light source, and a packaged IC viewed from the top.  
         [0021]    [0021]FIG. 11 is a mechanical drawing of a socket, a light source and a packaged IC viewed from the top.  
         [0022]    [0022]FIG. 12 is a mechanical drawing of a socket, a light source, and a packaged IC viewed from the top. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0023]    [0023]FIG. 1 is a mechanical drawing of a socket,  100  and light source,  114 , viewed from the top. Socket holes, which provide connections for IC contacts (e.g. pins, BGA balls, or other electrical or optical contacts),  102 , are represented by small circles in FIG. 1. In this embodiment, the light source,  114  is physically mounted to the top of the socket,  100 . The light source is electrically connected to a positive voltage and to socket hole  112 . Socket hole  110  is connected to a ground. When a packaged IC is correctly oriented in the socket,  100 , the packaged IC provides a ground path from socket hole  112  to socket hole  110 . Providing a ground path from socket hole  112  to socket hole  110  allows current to be conducted through light source,  114 , activating the light source. An activated light source, in this example, indicates the packaged IC is oriented correctly. Socket holes,  106  and  108 , are not connected to a ground or any reference voltage.  
         [0024]    [0024]FIG. 2 is a mechanical drawing of a socket,  208 , a light source,  214 , and a packaged IC,  200 , viewed from the side. In this embodiment, the light source,  214 , is physically mounted to the top of the socket,  208 . The light source,  214 , is electrically connected,  216 , to a positive voltage,  220  and to socket hole  212 . Socket hole,  210 , provides a path to a ground,  218 .  
         [0025]    In this example, packaged IC,  200 , is correctly oriented in socket  208  when pin  202  is inserted in socket hole  210 , and pin  206  is inserted in socket hole  212 . When pin  202  is inserted in socket hole  210 , and pin  206  is inserted in socket hole  212 , a ground path,  204 , is provided by the packaged IC,  200 , from socket hole  212  to ground,  218 . Providing a ground path,  204 , from socket hole  212  to ground,  218 , allows current to be conducted through light source,  214 , activating the light source,  214 . An activated light source,  214 , in this example, indicates the packaged IC,  200 , is oriented correctly.  
         [0026]    [0026]FIG. 3 is a mechanical drawing of a socket,  308 , a light source,  314 , and a packaged IC,  300 , viewed from the top. In this embodiment, the light source,  314 , is physically mounted to the top of the socket,  308 . Socket hole  312  is electrically connected to one lead of light source  314  and a positive voltage is electrically connected to the other lead of light source  314 . Socket hole,  310 , is this example, is connected to an external ground. Socket holes  320  and  322  are not connected to a ground or a reference voltage.  
         [0027]    Pin  302  is electrically connected through ground path,  304 , to pin  306 . Pins  316  and  318  on packaged IC  300  are not connected to a ground or a voltage reference. To correctly insert packaged IC,  300 , into, socket  308 , pin  302  is inserted in to socket hole  310 , pin  306  is inserted into socket hole  312 , pin  316  is inserted into socket hole  320 , and pin  318  is inserted into socket hole  322 . When packaged IC  300  is correctly inserted into socket  308 , a ground path,  304 , is provided from socket hole  312  to socket hole  310 . In this example, socket hole  310  is connected to an external ground. Providing a ground path,  304 , from socket hole  312  to grounded socket hole,  310 , allows current to be conducted through light source,  314 , activating the light source,  314 . An activated light source,  314 , in this example, indicates the packaged IC,  300 , is oriented correctly.  
         [0028]    [0028]FIG. 4 is a mechanical drawing of a socket,  408 , a light source,  414 , and a packaged IC,  400 , viewed from the top. In this embodiment, the light source,  414 , is physically mounted to the top of the socket,  408 . Socket hole  412  is electrically connected to one lead of light source  414  and a positive voltage is electrically connected to the other lead of light source  414 . Socket hole,  410 , is this example, is connected to an external ground. Socket holes  420  and  422  are not connected to a ground or a reference voltage.  
         [0029]    Pin  402  is electrically connected through ground path  404  to pin  406 . Pins  416  and  418  on packaged IC  400  are not connected to a ground or a voltage reference. In this example, packaged IC,  400  is incorrectly inserted into socket  408 , when pin  402  is inserted in to socket hole  420 , pin  406  is inserted into socket hole  410 , pin  416  is inserted into socket hole  422 , and pin  418  is inserted into socket hole  412 . In this example, when packaged IC  400  is incorrectly inserted into socket  408 , no ground path is provided from socket hole  412  to socket hole  410 . An inactivated light source,  414 , in this example, indicates the packaged IC,  400 , is oriented incorrectly.  
         [0030]    [0030]FIG. 5 is a mechanical drawing of a socket,  508 , a light source,  514 , and a packaged IC,  500 , viewed from the top. In this embodiment, the light source,  514 , is physically mounted to the top of the socket,  508 . Socket hole  512  is electrically connected to one lead of light source  514  and a positive voltage is electrically connected to the other lead of light source  514 . Socket hole,  510 , is this example, is connected to an external ground. Socket holes  520  and  522  are not connected to a ground or a reference voltage.  
         [0031]    Pin  502  is electrically connected through ground path  504  to pin  506 . Pins  516  and  518  on packaged IC  500  are not connected to a ground or a voltage reference. In this example, packaged IC,  500  is incorrectly inserted into socket  508 , when pin  502  is inserted in to socket hole  522 , pin  506  is inserted into socket hole  520 , pin  516  is inserted into socket hole  512 , and pin  518  is inserted into socket hole  510 . In this example, when packaged IC  500  is incorrectly inserted into socket  508 , no ground path is provided from socket hole  512  to socket hole  510 . An inactivated light source,  514 , in this example, indicates the packaged IC,  500 , is oriented incorrectly.  
         [0032]    [0032]FIG. 6 is a mechanical drawing of a socket,  608 , a light source,  614 , and a packaged IC,  600 , viewed from the top. In this embodiment, the light source,  614 , is physically mounted to the top of the socket,  608 . Socket hole  612  is electrically connected to one lead of light source  614  and a positive voltage is electrically connected to the other lead of light source  614 . Socket hole,  610 , is this example, is connected to an external ground. Socket holes  620  and  622  are not connected to a ground or a reference voltage.  
         [0033]    Pin  602  is electrically connected through ground path  604  to pin  606 . Pins  616  and  618  on packaged IC  600  are not connected to a ground or a voltage reference. In this example, packaged IC,  600  is incorrectly inserted into socket  608 , when pin  602  is inserted in to socket hole  612 , pin  606  is inserted into socket hole  622 , pin  616  is inserted into socket hole  610 , and pin  618  is inserted into socket hole  620 . In this example, when packaged IC  600  is incorrectly inserted into socket  608 , no ground path is provided from socket hole  612  to socket hole  610 . An inactivated light source,  614 , in this example, indicates the packaged IC,  600 , is oriented incorrectly.  
         [0034]    [0034]FIG. 7 is a mechanical drawing of a socket,  708 , an audio source,  714 , and a packaged IC,  700 , viewed from the side. In this embodiment, the audio source,  714 , is physically mounted to the top of the socket,  708 . The audio source,  714 , is electrically connected,  716 , to a positive voltage,  720  and to socket hole  712 . Socket hole,  710 , provides a path to a ground,  718 .  
         [0035]    In this example, packaged IC,  700 , is correctly oriented in socket  708  when pin  702  is inserted in socket hole  710 , and pin  706  is inserted in socket hole  712 . When pin  702  is inserted in socket hole  710 , and pin  706  is inserted in socket hole  712 , a ground path,  704 , is provided by the packaged IC,  700 , from socket hole  712  to ground,  718 . Providing a ground path,  704 , from socket hole  712  to ground,  718 , allows current to be conducted through the audio source,  714 , activating the audio source,  714 . An activated audio source,  714 , in this example, indicates the packaged IC,  700 , is oriented correctly.  
         [0036]    [0036]FIG. 8 is a mechanical drawing of a socket,  808 , a resistor,  814 , and a packaged IC,  800 , viewed from the side. In this embodiment, the resistor,  814 , is physically mounted to the top of the socket,  808 . The resistor,  814 , is electrically connected,  816 , to a positive voltage,  820 , sense contact,  822 , and to socket hole  812 . Socket hole,  810 , provides a path to a ground,  818 .  
         [0037]    In this example, packaged IC,  800 , is correctly oriented in socket  808  when pin  802  is inserted in socket hole  810 , and pin  806  is inserted in socket hole  812 . When pin  802  is inserted in socket hole  810 , and pin  806  is inserted in socket hole  812 , a ground path,  804 , is provided by the packaged IC,  800 , from socket hole  812  to ground,  818 . Providing a ground path,  804 , from socket hole  812  to ground,  818 , allows current to be conducted through the resistor,  814 , which establishes a voltage on sense contact  822 . The voltage on the sense contact,  822 , may be used to drive external equipment. A voltage near ground on sense contact,  822 , indicates the packaged is oriented correctly.  
         [0038]    [0038]FIG. 9 is a mechanical drawing of a socket,  908 , a light source,  914 , and a packaged IC,  900 , viewed from the top. In this embodiment, the light source,  914 , is physically mounted to the top of the socket,  908 . Socket hole  912  is electrically connected to one lead of light source  914  and a positive voltage is electrically connected to the other lead of light source  914 . Socket holes,  910 ,  920 , and  922  in this example, are connected to an external ground.  
         [0039]    Pin  902  is electrically connected through ground path  904 , to pin  916  and pin  916  is electrically connected through ground path  924  to pin  918 . Pin  906  on packaged IC  900  is not connected to a ground or a voltage reference. To correctly insert packaged IC,  900 , into, socket  908 , pin  902  is inserted in to socket hole  910 , pin  906  is inserted into socket hole  912 , pin  916  is inserted into socket hole  920 , and pin  918  is inserted into socket hole  922 . When packaged IC  900  is correctly inserted into socket  908 , no ground path is provided from socket hole  912 . An inactivated light source,  914 , in this example, indicates the packaged IC,  900 , is oriented correctly.  
         [0040]    [0040]FIG. 10 is a mechanical drawing of a socket,  1008 , a light source,  1014 , and a packaged IC,  1000 , viewed from the top. In this embodiment, the light source,  1014 , is physically mounted to the top of the socket,  1008 . Socket hole  1012  is electrically connected to one lead of light source  1014  and a positive voltage is electrically connected to the other lead of light source  1014 . Socket holes,  1010 ,  1020 , and  1022  in this example, are connected to an external ground.  
         [0041]    Pin  1002  is electrically connected through ground path  1004  to pin  1016  and pin  1016  is electrically connected through ground path  1024  to pin  1018 . Pin  1006  on packaged IC  1000  is not connected to a ground or a voltage reference. When packaged IC  1000  is incorrectly inserted into socket  1008 , in this example, pin  1006  is inserted in to socket hole  1010 , pin  1018  is inserted into socket hole  1012 , pin  1002  is inserted into socket hole  1020 , and pin  1016  is inserted into socket hole  1022 . When packaged IC  1000  is incorrectly inserted into socket  1008 , in this example, a ground path is provided from socket hole  1012  to a ground. An activated light source,  1014 , in this example, indicates the packaged IC,  1000 , is oriented incorrectly.  
         [0042]    [0042]FIG. 11 is a mechanical drawing of a socket,  1108 , a light source,  1114 , and a packaged IC,  1100 , viewed from the top. In this embodiment, the light source,  1114 , is physically mounted to the top of the socket,  1108 . Socket hole  1112  is electrically connected to one lead of light source  1114  and a positive voltage is electrically connected to the other lead of light source  1114 . Socket holes,  1110 ,  1120 , and  1122 , in this example, are connected to an external ground.  
         [0043]    Pin  1102  is electrically connected through ground path  1104  to pin  1116  and pin  1116  is electrically connected through ground path  1124  to pin  1118 . Pin  1106  on packaged IC  1100  is not connected to a ground or a voltage reference. When packaged IC  1100  is incorrectly inserted into socket  1108 , in this example, pin  1118  is inserted in to socket hole  1110 , pin  1116  is inserted into socket hole  1112 , pin  1106  is inserted into socket hole  1120 , and pin  1102  is inserted into socket hole  1122 . When packaged IC  1100  is incorrectly inserted into socket  1108 , in this example, a ground path is provided from socket hole  1112  to a ground. An activated light source,  1114 , in this example, indicates the packaged IC,  1100 , is oriented incorrectly.  
         [0044]    [0044]FIG. 12 is a mechanical drawing of a socket,  1208 , a light source,  1214 , and a packaged IC,  1200 , viewed from the top. In this embodiment, the light source,  1214 , is physically mounted to the top of the socket,  1208 . Socket hole  1212  is electrically connected to one lead of light source  1214  and a positive voltage is electrically connected to the other lead of light source  1214 . Socket holes,  1210 ,  1220 , and  1222 , in this example, are connected to an external ground.  
         [0045]    Pin  1202  is electrically connected through ground path  1204  to pin  1216  and pin  1216  is electrically connected through ground path  1224  to pin  1218 . Pin  1206  on packaged IC  1200  is not connected to a ground or a voltage reference. When packaged IC  1200  is incorrectly inserted into socket  1208 , in this example, pin  1216  is inserted in to socket hole  1210 , pin  1202  is inserted into socket hole  1212 , pin  1218  is inserted into socket hole  1220 , and pin  1206  is inserted into socket hole  1222 . When packaged IC  1200  is incorrectly inserted into socket  1208 , in this example, a ground path is provided from socket hole  1212  to a ground. An activated light source,  1214 , in this example, indicates the packaged IC,  1200 , is oriented incorrectly.  
         [0046]    The foregoing description of the present invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed, and other modifications and variations may be possible in light of the above teachings. The embodiment was chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and various modifications as are suited to the particular use contemplated. It is intended that the appended claims be construed to include other alternative embodiments of the invention except insofar as limited by the prior art.