Patent ID: 7538600

Claim:
A voltage generator comprising: a pumping voltage detecting section configured to detect a level of a pumping voltage in accordance with a reference voltage, activate a pumping enable signal when the detected level of the pumping voltage is higher than a first voltage, while activating a power source voltage drive signal when the detected level of the pumping voltage is lower than the first voltage; a pumping section configured to generate the pumping voltage through a pumping operation when the pumping enable signal is active; and a power source voltage driving section configured to generate the pumping voltage at a level of an external power source voltage when the power source voltage drive signal is active, wherein the pumping voltage detecting section comprises: a pumping voltage dividing section configured to divide the pumping voltage, generate a first divisional voltage and a second divisional voltage lower than the first divisional voltage; a power source voltage drive controlling section configured to compare the first divisional voltage with the reference voltage and drive a external power source voltage in accordance with a result of the comparison, and generate the power source voltage drive signal; a pumping enable signal generating section configured to compare the second divisional voltage with the reference voltage and drive the external power source voltage in accordance with a result of the comparison, and generate a first pumping enable signal; and a pumping voltage drive controlling section configured to generate a second pumping enable signal from a logical operation of the power source voltage drive signal and the first pumping enable signal.