Static power is the main source of power consumption in SRAMs. The conventional 6T-SRAM cell is shown in Figure 1b. The cell consists of two back-to-back inverters (M1-M4) and two access transistors (M5, M6). This cell uses the same path for both read and write operations, and most of the cell failures occur due to the read mode issues. A 5T-SRAM cell is an asymmetric type of SRAM cell (see Figure 1c). This cell leaves out one of the pull-up PMOS transistors in order to decrease the strength of back-to-back inverter, which lowers the static power. The correct functionality of this cell over a wide range of supply voltages has been verified in previous work. We observe that this cell provides a novel opportunity to save static power when storing ‘one’ in Q node. During this operation, the single pull-up PMOS transistor is in OFF mode and disconnects the Vdd from storage nodes. This reduces the energy consumption of writing ‘one’ on 5T cells.
M1