POWER UP CIRCUIT FOR SEMICONDUCTOR MEMORY DEVICE

摘要

PURPOSE: A power-up apparatus of semiconductor memory is provided to reduce the power consumption and to minimize influences of noise by ensuring an initial value when a power-up signal is set and enabling a normal power-up signal when the electric power is extremely fluctuated by the noise. CONSTITUTION: A power-up detecting unit(10) enables a power-up signal(PWRUP) by detecting the state of power-on. A power-up low ensuring unit(20) receives the power-up signal(PWRUP) and an output signal from the power-up detecting unit(10). The power-up low ensuring unit(20) is connected to between a power source(Vcc) and a first node(N1) to ensure an initial value of the power-up signal(PWRUP). A capacitor(30) is coupled to between the first node(N1) and the ground(Vss) to make the initial value of the power-up signal(PWRUP) to low state. A latch(40) is connected to between the first node(N1) and a second node(N2) to eliminate noise. A power-up driver(50) is coupled to the second node(N2) to drive the power-up signal(PWRUP).