Abstract:
A through socket includes a socket body, which can load the plurality of memory modules, and a plurality of internally connected socket conductors arranged to electrically connect the memory modules when loaded. A turn around socket includes a socket body for loading at least one memory module and connecting a contact of one surface of a loaded memory module to a contact of the other surface. Using at least one through socket and at least one turn around socket, the memory system can extend a plurality of memory modules on a printed circuit board (PCB). A memory module adapted for use in the memory system has four contacts arranged at both ends and on both surfaces.

Description:
This application claims priority from Korean Patent Application No. 00-60705, filed Oct. 16, 2000 in the name of Samsung Electronics Co., Ltd., which is herein incorporated by reference. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a wiring connection apparatus of an electronic device, and more particularly, to a socket, occupying a small area of a printed circuit board (PCB), enabling a plurality of modules to be easily extended, and a memory system using the socket. 
   2. Description of the Related Art 
   Computer systems often require graphics of high quality, requiring that the integration density and speed of a semiconductor memory device must be increased and the size of a semiconductor memory device must be reduced. A memory module changes corresponding to the changes in the semiconductor memory device. In particular, since a greater amount of memory than the amount used in conventional technology is required for real time processing of three dimensional data, a greater number of memory module boards must be loaded on a main board. 
     FIG. 1  shows a first example of conventional sockets loaded on a printed circuit board (PCB) and memory modules connected to the sockets. A PCB  10  includes two conventional sockets  11  and  12  installed to be parallel with each other and two conventional memory modules  13  and  14  loaded on the sockets  11  and  12 . 
   The memory modules  13  and  14  connected to the two conventional sockets  11  and  12  are connected to a central processing unit (not shown) in parallel through a plurality of data bus lines  15  and a plurality of signal lines  16 . 
     FIG. 2  shows a second example of conventional sockets loaded on a PCB and memory modules connected to the sockets. The PCB  10  includes two conventional sockets  11  and  12  installed to be parallel with each other on the PCB  10  and two memory modules  23  and  24  connected to the conventional sockets  11  and  12 . 
   The memory modules  23  and  24  connected to the sockets  11  and  12  are serially connected to the CPU (not shown) through the plurality of data bus lines  15  and the plurality of signal lines  16 . In this example, the memory modules  23  and  24  are formed so that the data bus lines  15  and signal lines  16  run up along on one side and down the opposite side via a path (indicated by the solid-and-dotted lines). 
     FIGS. 3A and 3B  are sectional views showing base sockets for loading memory modules used in a conventional PCB.  FIG. 3A  shows a base socket where the memory module is loaded parallel to the PCB.  FIG. 3B  shows a base socket where the memory module is loaded perpendicular to the PCB. 
   Referring to  FIGS. 3A and 3B , the base sockets are attached to a PCB  34  by soldering socket fixing means  32  included in the base sockets. 
   The base sockets include socket bodies  30   a  and  30   b  and two socket conductors  33  for connecting the contacts of both surfaces of a memory module board  31 . The two socket conductors  33  pass through the insides of the socket bodies  30   a  and  30   b  and are connected to corresponding printed circuit patterns (not shown) of the PCB  34 . 
   Referring to  FIGS. 1 through 3B , the number of memory modules used in a conventional system board is restricted by the number of sockets loaded on the system board (that is, the PCB) and installed so as to connect to the memory modules. When four sockets are loaded, the number of memory modules that can be loaded is restricted to four. The number of memory modules cannot be increased or decreased. When a user needs to use only two memory modules, the remaining two sockets are wasted. 
   Therefore, when a significantly large number of sockets for the memory modules are installed, the size of the PCB is large. When a small number of sockets for the memory modules are installed, it is difficult to extend memory capacity. 
   SUMMARY OF THE INVENTION 
   The present disclosure provides a through socket and a turn around socket, designed to extend a plurality of memory modules without increasing the size of a printed circuit board (PCB). The disclosure further provides a memory system for extending a plurality of memory modules using the sockets. 
   A through socket includes a socket body, arranged to load first and second memory modules, and a first conductor, arranged to connect a contact on one surface of the first memory module to a contact on one surface of the second memory module. The through socket further comprises a second conductor arranged to connect a contact on the other surface of the first memory module to a contact on the other surface of the second memory module. 
   A turn around socket comprises a socket body arranged to load a first memory module, and a first conductor arranged to connect a contact on one surface of the first memory module to a contact on the other surface of the first memory module. 
   A memory system according to the present disclosure includes a plurality of memory modules. At least one through socket is provided for electrically connecting at least two memory modules of the plurality of memory modules. As well, the memory system further includes at least one turn around socket for electrically connecting at least one surface of one of the plurality of memory modules to the other surface of the same memory module. 
   A memory module adapted for use in the present memory system comprises a printed circuit board having first and second surfaces and first and second ends. A plurality of memory devices are loaded on the first and second surfaces of the memory module. Four contacts are arranged at the first and second ends of the first and second surfaces of the memory module, the contacts being operative as electrical paths. 
   The present invention will become more apparent by describing in detail preferred embodiments thereof with reference to the attached drawings, in which the same reference numerals in different drawings represent the same element. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  shows a first example of conventional sockets loaded on a printed circuit board (PCB) and memory modules connected to the sockets; 
       FIG. 2  shows a second example of conventional sockets loaded on a PCB and memory modules connected to the sockets; 
       FIGS. 3A and 3B  are sectional views of conventional sockets for loading memory modules used in the PCB; 
       FIG. 4  is a sectional view of a through socket according to a first embodiment of the present invention; 
       FIG. 5  is a sectional view of a through socket according to a second embodiment of the present invention; 
       FIG. 6  is a sectional view of a through socket according to a third embodiment of the present invention; 
       FIG. 7  is a sectional view of a turn around socket according to a first embodiment of the present invention; 
       FIG. 8  is a sectional view of a turn around socket according to a second embodiment of the present invention; 
       FIGS. 9A ,  9 B, and  9 C show a first applied example of the first embodiment of the through socket and the first embodiment of the turn around socket, the electrical connection of the first applied example, and a three dimensional perspective of a real PCB, respectively; 
       FIGS. 10A and 10B  show a second applied example of the first embodiment of the through socket and the first embodiment of the turn around socket and the electrical connection of the second applied example, respectively; 
       FIGS. 11A and 11B  show a third applied example of the second embodiment of the through socket and the first embodiment of the turn around socket and the electrical connection of the third applied example, respectively; 
       FIGS. 12A and 12B  show a fourth applied example of the first embodiment of two through sockets and the first embodiment of the turn around socket and the electrical connection of the fourth applied example, respectively; 
       FIGS. 13A and 13B  show a fifth applied example of the first embodiment of two through sockets and the first embodiment of the turn around socket and the electrical connection of the fifth applied example, respectively; 
       FIGS. 14A and 14B  show a sixth applied example of the second embodiment of two through sockets and the first embodiment of the turn around socket and the electrical connection of the sixth applied example, respectively; 
       FIG. 15A  shows a seventh applied example of the second embodiment of the through socket, the third embodiment of the through socket and the second embodiment of the turn around socket; and 
       FIG. 15B  shows the electrical connection of the seventh applied example. 
   

   DETAILED DESCRIPTION OF THE EMBODIMENTS 
   A through socket according to one embodiment of the present invention is shown in sectional side view in  FIG. 4 . The through socket includes a socket body  400  for loading a first memory module  41  and a second memory module  42  in opposite directions. A first socket conductor  401  electrically connects a contact located on one surface of the first memory module  41  to a contact located on one surface of the second memory module  42  by passing through the socket body  400 . A second socket conductor  402  electrically connects a contact located on the other surface of the first memory module  41  to a contact located on the other surface of the second memory module  42  by passing through the socket body  400 . 
   Referring to  FIG. 5 , another embodiment of the through socket includes a socket body  500  for loading a first memory module  51  and a second memory module  52  in the same direction. A first socket conductor  501  electrically connects a contact located on one surface of the first memory module  51  to a contact located on one surface of the second memory module  52  by passing through the socket body  500 . A second socket conductor  502  electrically connects a contact located on the other surface of the first memory module  51  to a contact located on the other surface of the second memory module  52  by passing through the socket body  500 . 
   A third through socket embodiment is shown in sectional view in  FIG. 6 . The through socket includes a socket body  600  for loading a first memory module  61 , a second memory module  62 , and a third memory module  63  in the same direction. A first socket conductor  601  electrically connects a contact located on one surface of the first memory module  61  to a contact located on one surface of the third memory module  63  by passing through the socket body  600 . A second socket conductor  602  electrically connects a contact located on the other surface of the first memory module  61  to a contact located on one surface of the second memory module  62  by passing through the socket body  600 . A third socket conductor  603  electrically connects a contact located on the other surface of the second memory module  62  to a contact located on the other surface of the third memory module  63 . The advantage of the daisy-chain configuration of the electrical connections, as exemplified in  FIG. 6 , is discussed in the several applied examples, below. 
   A turn around socket according to one embodiment of the present invention is shown in  FIG. 7 . The turn around socket includes a socket body  700  for loading a memory module  71  and a first socket conductor  701  for electrically connecting the contacts ( 93 ,  FIG. 9C ) of both sides of the memory module  71  by passing through the socket body  700 . 
   Referring to a second embodiment turn around socket ( FIG. 8 ), the turn around socket similarly includes a socket body  800  for loading a first memory module  81  and a second memory module  82  in the same direction, a first socket conductor  801  for electrically connecting the contacts of both surfaces of the first memory module  81  by passing through the socket body  800 , and a second socket conductor  802  for electrically self-connecting the contacts of both surfaces of the second memory modules  82  by passing through the socket body  800 . 
     FIG. 9A  is a sectional side view showing a first applied example of the first embodiment of the through socket and the first embodiment of the turn around socket.  FIG. 9B  diagrams the electrical connection of the first applied example shown in  FIG. 9A .  FIG. 9C  is a perspective view showing the first applied example on a printed circuit board (PCB). 
   Turning now to  FIG. 9A , the first applied example comprises a first memory module  91  loaded in a base socket  30   a  installed on a PCB  34 . The first memory module  91  is connected to a second memory module  92  by a through socket  400 . A turn around socket  700  is loaded on the upper portion of the second memory module  92 . 
   In the first applied example ( FIG. 9A ), memory groups MG 1  through MG 4  are electrically and serially connected to each other in the following order: MG 1 , MG 3 , MG 4 , and MG 2  ( FIG. 9B ). An electrical connection in the reverse order is also possible. Memory groups MG 1  through MG 4  refer to the set of a plurality of memories loaded on both surfaces of the memory modules. 
   In use, a first memory module  91  is loaded in a base socket loaded on a PCB  10  ( FIG. 9C ). The through socket  400  is installed between the first memory module  91  and the second memory module  92 . The turn around socket  700  is loaded on the upper portion of the second memory module  92 . 
   In a second applied example ( FIG. 10A ), the first memory module  91  is loaded in a base socket  30   b  installed on a PCB  34 . The first memory module  91  is connected to the second memory module  92  by the through socket  400 . The turn around socket  700  is loaded at one end of the second memory module  92 . 
   In the first embodiment shown in  FIG. 10A , the memory groups MG 1  through MG 4  are electrically and serially connected to each other in the following order: MG 2 , MG 4 , MG 3 , and MG 1  ( FIG. 10B ). An electrical connection in the reverse order is also possible. 
     FIG. 11A  shows a third applied example of the second embodiment of the through socket and the first embodiment of the turn around socket. In this applied  5  example, the first memory module  91  is loaded in a base socket  30   b  installed on the PCB  34 . The first memory module  91  is connected to the second memory module  92  by a through socket  500 . The turn around socket  700  is loaded at one end of the second memory module  92 . 
     FIG. 11B  shows the electrical connection of the third applied example shown in  FIG. 11A . The memory groups MG 1  through MG 4  are electrically and serially connected to each other in the following order: MG 1 , MG 4 , MG 3 , and MG 2 . An electrical connection in the reverse order is also possible. 
   The first, second and third applied examples disclose various methods for loading two memory modules on a PCB in a vertical direction, horizontal direction, and horizontal and vertical directions, respectively. 
   The present sockets and memory system can also be utilized to load three memory modules, as shown in a fourth applied example of the first embodiment of two through sockets and the first embodiment of the turn around socket ( FIG. 12A ). In the fourth applied example, a first memory module  121  is loaded in the base socket  30   a  installed on the PCB  34 . The first memory module  121  is connected to a second memory module  122  by a through socket  400 - 1 , and the second memory module  122  is connected to a third memory module  123  by a connection socket  400 - 2 . The turn around socket  700  is loaded at one end of the third memory module  123 . 
   The electrical connection of the fourth applied example, above, is shown in  FIG. 12B . Memory groups MG 5  through MG 10  are electrically and serially connected in the following order: MG 5 , MG 7 , MG 9 , MG 10 , MG 8 , and MG 6 . An electrical connection in the reverse order is also possible. 
   Similarly,  FIG. 13A  shows a fifth applied example of the first embodiment of two through sockets and the first embodiment of the turn around socket.  FIG. 13B  diagrams the electrical connection of the fifth applied example shown in  FIG. 13A . 
   Referring to  FIG. 13A , in the fifth applied example, the first memory module  121  is loaded in the base socket  30   b  installed on the PCB  34 . The first memory module  121  is connected to the second memory module  122  by the through socket  400 - 1 , and the second memory module  122  is connected to the third memory module  123  by the through socket  400 - 2 . The turn around socket  700  is loaded at one end of the third memory module  123 . 
   In the fifth applied example, memory groups MG 5  through MG 10  are electrically and serially connected in the following order: MG 6 , MG 8 , MG 10 , MG 9 , MG 7 , and MG 5  ( FIG. 13B ). An electrical connection in the reverse order is also possible. 
   As shown in  FIG. 14A , in the sixth applied example, the first memory module  121  is loaded in the base socket  30   b  installed on the PCB  34 . The first memory module  121  is connected to the second memory module  122  by a through socket  500 - 1 , and the second memory module  122  is connected to the third memory module  123  by a through socket  500 - 2 . The turn around socket  700  is loaded at one end of the third memory module  123 . The contacts of the memory modules loaded in sockets  500 - 1  and  500 - 2  are connected in a daisy-chain configuration. 
     FIG. 14B  shows the electrical connection of the sixth applied example shown in  FIG. 14A . In the sixth applied example shown in  FIG. 14A , memory groups MG 5  through MG 10  are electrically and serially connected to each other in the following order: MG 5 , MG 8 , MG 9 , MG 10 , MG 7 , and MG 6 . It should be apparent that an electrical connection in the reverse order is also possible. 
   Referring to  FIG. 12A  through  FIG. 14B , the fourth through sixth applied examples disclose various methods of loading three memory modules on the PCB in the vertical direction, the horizontal direction, and the horizontal and vertical directions, respectively. 
   As shown in  FIGS. 12A and 12B , since the plurality of through sockets and memory modules are serially connected, it is theoretically possible to infinitely extend the memory modules. 
   A seventh applied example of the second embodiment of the through socket, the third embodiment of the through socket, and the second embodiment of the turn around socket is shown in  FIG. 15A . In the seventh applied example, a first memory module  151  is loaded in the base socket  30   b  installed on the PCB  34 . The first memory module  151  is connected to a second memory module  152  by a through socket  500 . The second memory module  152  is loaded in the lower stage of a through socket  600 . A third memory module  153  is loaded in the middle stage of the through socket  600  and in the lower stage of the turn around socket  800 . The fourth memory module  154  is loaded in the other stage of the turn around socket  800  and the upper stage of the third through socket  600 . The contacts of the memory modules loaded in sockets  500  and  600  are connected in a daisy-chain configuration. 
     FIG. 15B  shows the electrical connection of the seventh applied example shown in  FIG. 15A . Memory groups MG 11  through MG 18  are electrically and serially connected to each other in the following order: MG 11 , MG 14 , MG 15 , MG 16 , MG 17 , MG 18 , MG 13 , and MG 12 . As with other applied examples described above, an electrical connection in the reverse order is likewise possible. 
   Having described and illustrated the principles of the invention in a preferred embodiment thereof, it should be apparent that the invention can be modified in arrangement and detail without departing from such principles. Accordingly, such changes and modifications are considered to fall within the scope of the following claims.