LOCAL CHARGE PUMP CIRCUIT OF NONVOLATILE SEMICONDUCTOR MEMORY DEVICE

摘要

PROBLEM TO BE SOLVED: To secure a sufficient program voltage margin irrespective of a source voltage, by setting a switching voltage stabilization circuit. SOLUTION: A switching voltage stabilization circuit is composed of an inverter 112 and a capacitor 113, discharging a node 111 while a clock pulse signal OP output from an oscillator 101 maintains a source voltage level. The stabilization circuit charges the node 111 while the clock pulse signal OP maintains a ground voltage level so that a switching voltage on the mode 111 is kept in a constant size. A sufficient high voltage necessary for programming is obtained irrespective of a change of a source voltage, and therefore a sufficient program voltage margin is secured.