Internal power supply voltage generating circuit of semiconductor memory device

摘要

A flexible internal power supply voltage generating circuit of a semiconductor memory device includes a step-down circuit and a selection circuit. The selection circuit selects the step-down circuit for use when the semiconductor device uses a high external power supply voltage but bypasses the step-down circuit for a low external power supply voltage. One such circuit additionally includes a power supply terminal and a control circuit. The power supply terminal receives an external power supply voltage. The control circuit compares a feedback internal power supply voltage with a reference voltage at the time of driving a word line and then generates a control voltage signal for controlling a DIP of an internal power supply voltage caused by driving the word line. A selection circuit selectively connects a high voltage node or a low voltage node to the power supply terminal according to the external power supply voltage. The step-down circuit connects to the high voltage node and reduces the external power supply voltage when the power supply terminal receives the high supply voltage. The driver is between a common connection point of the step-down circuit and the low voltage node and an internal circuit and drives the external power supply voltage in the internal circuit in response to the control signal. Accordingly, when a high voltage is applied, the high voltage is stepped down and provided to the driver, thereby controlling a reverse overshoot of the internal power supply voltage.