New input/output designs for high speed static CMOS RAM

New input and output schematics and optimum design for cell and array are proposed, and applied to a 256×4 bit CMOS static RAM. Simplified decoder circuit with effective decoder control circuit has a high speed and a wide timing margin. Simple sense amplifier and compact output circuit bring higher speed and reduction in pattern area. Using p-channel transfer gate for memory cell and array, the switching speed and operational stability are much improved. The device is fabricated by 5 μm layout rule Si-gate CMOS technology. An 80 ns access time and 100 ns minimum cycle time are acquired at 5 V supply. Power dissipation is less than 7.5 mW at 1 MHz operation.