A 14-ns 1-Mbit CMOS SRAM with variable bit organization

The authors describe a 14-ns 1-Mb CMOS SRAM (static random-access memory) with both 1M word×1-b and 256 K word×4-b organizations. The desired organization is selected by forcing the state of an external pin. The fast access time is achieved by the use of a shorter divided-word-line (DWL) structure, a highly sensitive sense amplifier, a gate-controlled data-bus driver, and a dual-level precharging technique. The 0.7-μm double-aluminum and triple-polysilicon process technology with trench isolation offers a memory cell size of 41.6 μm² and a chip size of 86.6 mm ². The variable bit-organization function reduces the testing time while keeping the measurement accuracy of the access times