Power efficient SRAM design with integrated bit line charge pump

Abstract

Bit line toggling of SRAM systems in write operations leads to the largest portion of power dissipation. To reduce this amount of power loss and achieve power efficient memory, we propose a new SRAM design that integrates charge pump circuits to harvest and reuse bit line charge. In this work, a power-efficient charge recycling SRAM is designed and implemented in 180nm CMOS technology. Post-layout simulation demonstrates an 11% of power saving and 3.8% of area overhead, if the bit width of SRAM is chosen as 8. Alternatively, 22% of power reduction is obtained if the bit width of SRAM is extended to 64. Compared with existing charge recycling SRAM schemes, this proposed SRAM is robust to process variation, demonstrates good read/write stability, and illustrates better trade-off between design complexity and power reduction.