Stacked Integrated Circuit Module

Abstract

The present invention provides an improvement on the use of flexible circuit connectors for electrically coupling IC devices to one another in a stacked configuration by use of the flexible circuit to provide the connection of the stacked IC module to other circuits. Use of the flexible circuit as the connection of the IC module allows the flexible circuit to provide strain relief and allows stacked IC modules to be assembled with a lower profile than with previous methods. The IC module can be connected to external circuits through the flexible circuit connectors by a variety of means, including solder pads, edge connector pads, and socket connectors. This allows for IC devices to occupy less space then with previous methods, which is beneficial in modules such as memory modules with multiple, stacked memory devices.

1 . A method for devising a circuit module comprising the steps of:
 providing first and second leaded packaged integrated circuits each with upper and lower major surfaces and leads emergent from first and second peripheral sides of the respective packages;   providing a flex circuit along the first surface of which are disposed first and second pluralities of connective sites and along the second major surface of which are disposed first and second pluralities of connective sites; and   reconfiguring the leads of the first and second leaded packaged integrated circuits so as to confine the leads to a space defined by first and second planes defined by the upper and lower major surfaces of the respective packages;   attaching the leads emergent from the first peripheral side of the first leaded packaged integrated circuit to the first plurality of connective sites of the first major surface of the flex circuit and attaching the leads emergent from the second peripheral side of the first leaded packaged integrated circuit to the second plurality of connective sites of the first major surface of the flex circuit so as to realize contact between the lower major surface of the first leaded packaged integrated circuit and the first major surface of the flex circuit and connecting the second leaded packaged integrated circuit to the first and second pluralities of connective sites of the second major surface of the flex circuit.   
   
   
       2 . The method of  claim 1  in which the flex circuit provided exhibits a third plurality of connective sites for connection of the circuit module to an application environment. 
   
   
       3 . The method of  claim 1  in which an adhesive is disposed between the lower major surface of the first leaded packaged memory circuit and the first major surface of the flex circuit. 
   
   
       4 . The method of  claim 2  in which the third plurality of connective sites is configured as a socket connector. 
   
   
       5 . The method of  claim 2  in which the third plurality of connective sites is configured for connection to an edge connector. 
   
   
       6 . The method of  claims 1  in which the first and second leaded packaged integrated circuits are flash memory circuits.