INTERNAL BOOSTER CIRCUIT IN SEMICONDUCTOR INTEGRATED CIRCUIT

摘要

PROBLEM TO BE SOLVED: To obtain a stabilized step-up voltage having sufficient level by suppressing the body effect of an output transistor. SOLUTION: Output from an oscillator 8 is applied to step-up capacitors 2, 4 in order to step-up the voltages at step-up nodes A, B, and the gate of an output transistor 6 is controlled by the step-up node B so as to output a step-up voltage VPP from the step-up node A through the output transistor 6. In such an internal voltage step-up circuit, the internal voltage level of an oscillator 8 is converted through a voltage converter 30 into a power supply voltage level and applied to the step-up capacitor 4 and/or 2. Since the step-up nodes A, B can be stepped up to at least 2VCC level, body effects of the output transistor 6 can be avoided.