Multi-stage dual replica bit-line delay technique for process-variation-robust timing of low voltage SRAM sense amplifier

A multi-stage dual replica bit-line delay （MDRBD） technique is proposed for reducing access time by suppressing the sense-amplifier enable （SAE） timing variation of low voltage static randomaccess memory （SRAM） applications. Compared with the traditional technique, this strategy, using statistical theory, reduces the timing variation by using multi-stage ideas, meanwhile doubling the replica bit-fine （RBL） capacitance and discharge path simultaneously in each stage. At a supply voltage of 0.6 V, the simulation results show that the standard deviations of the SAE timing and cycle time with the proposed technique are 69.2% and 47.2%, respectively, smaller than that with a conventional RBL delay technique in TSMC 65 nm CMOS technology （Taiwan Semiconductor Manufacturing Company, Taiwan）.