SRAM device employing stable virtual rail scheme against process-voltage-temperature variations

摘要

The present invention is disclosed with respect to the SRAM device according to the virtual rail scheme stable against various PVT variations . The SRAM device has a higher virtual ground supply voltage by the threshold voltage of the transistor from the lower power supply voltage and the virtual ground voltage from the power source voltage by the threshold voltage of the transistor cell in SRAM. By the power supply voltage of the diode type and is connected between the virtual power supply voltage PMOS transistor and NMOS transistor , and a ground voltage and a diode type of the NMOS transistor and PMOS transistor connected between the virtual ground voltage , stable for the various PVT variations virtual power supply voltage and the virtual ground voltage to provide a stable, low leakage current characteristics .