Semiconductor memory device and semiconductor memory device control method
View Patent ↗A cell core unit and its peripheral circuit are driven by a relatively low voltage power supply. A constant voltage that does not depend on the power supply voltage is provided as a boosted voltage (VBOOST) to be supplied to a control signal for a word line of the cell core unit. A sense amplifier amplifies a higher voltage level of a bit line to the power supply voltage. Then, a circuit for generating a signal for defining the transition timing and/or the pulse width of a control signal from the peripheral circuit to the cell core unit performs signal delay using a delay circuit having a characteristic in which a delay time thereof decreases with reduction of the provided power supply voltage.
1. A semiconductor memory device comprising:
a memory cell array having a plurality of memory cells arranged in an array form;
a voltage step down circuit that receives a power supply voltage and outputs a step down voltage that is lower than said power supply voltage;
a voltage step up circuit that receives said step down voltage and outputs a step up voltage;
a peripheral circuit outputting a word line voltage and receiving said step up voltage and said power supply voltage; and
a delay circuit being driven by said step down voltage, said delay circuit having a characteristic in which a delay time thereof decreases more when the voltage provided to the delay circuit is low than when the voltage provided to the delay circuit is high.
2. The semiconductor memory device according to claim 1 ,
wherein said peripheral circuit comprises;
a sense amplifier amplifying a high level voltage of a selected bit line to said power supply voltage; and
a word line driving circuit driving a selected word line by the step up voltage.