Low-Power Cache Design Using 7T SRAM Cell

On-chip cache consumes a large percentage of the whole chip area and expected to increase in advanced technologies. Charging/discharging large bit lines capacitance represents a large portion of power consumption during a write operation. We propose a novel write mechanism which depends only on one of the two bit lines to perform a write operation. Therefore, the proposed 7T SRAM cell reduces the activity factor of discharging the bit line pair to perform a write operation. Experimental results using HSPICE simulation shows that the write power saving is at least 49%. Both read delay and static noise margin are maintained after carefully sizing the cell transistors