Patent ID: 7986180

Claim:
A method for driving a semiconductor memory device, comprising: generating a first reference signal having a first voltage level and a compensating signal having a second voltage level lower than the first voltage level by a predetermined level; generating an internal voltage in response to the first reference signal; comparing the compensating signal with a voltage derived from the internal voltage; compensating the internal voltage based on the comparison result; and comparing the compensating signal with a comparing voltage to generate a supply voltage detection signal and changing a state of a transistor coupled between a power supply voltage and the internal voltage from a switched-off state to a switched-on state in response to the supply voltage detection signal to further compensate the internal voltage when the power supply voltage becomes lower than a first threshold level, wherein the comparing voltage is generated from the power supply voltage and the generating of the first reference signal and the compensating signal includes generating the first reference signal by dividing the power supply voltage and generating the compensating signal by dividing the first reference signal.