Push-Pull Read/Write Port Circuit for Multi-Port Array Cells
Original Publication Date: 1986-Apr-01
Included in the Prior Art Database: 2005-Mar-08
A single Read/Write port replaces two ports, one Read and one Write, in a multi-port array cell application by use of the disclosed push-pull Read/Write port circuit (PPRWPC). Three bit lines and one word line per read/write port are eliminated, thereby increasing the number of wiring channels available to such applications at a cost of three additional resistors and three SBDs (Schottky barrier diodes). Fig. 1 shows an array cell connected through a single PPRWPC to a Bit Line and a Word Line. It functions as follows: There are two Bit Line states, 'down' and 'up', and three Word Line states, 'down', 'standby' (intermediate), and 'up'. When the Word Line is 'down', the cell is being 'read' and the push-pull 'write' circuit is in its high impedance state.