Patent ID: 7755417

Claim:
A voltage generating circuit comprising: a pumping circuit configured to boost a power supply voltage in accordance with a charge transfer operation; a voltage detection circuit configured to detect the output voltage of the pumping circuit; a first pumping control circuit configured to control the pumping circuit in accordance with the output of the voltage detection circuit; and a second pumping control circuit configured to control the pumping circuit in place of the first pumping control circuit when the output voltage of the pumping circuit is in a certain range; wherein the pumping circuit comprises, a charge transfer circuit having multiple diodes connected in series between a power supply node and the voltage output node of the pumping circuit and capacitors, one ends thereof being coupled to the respective connection nodes of the diodes, for boosting the power supply voltage in accordance with one directional charge transferring, a first clock generating circuit selected by the first pumping control circuit to drive the other ends of the capacitors of the charge transfer circuit with a constant clock frequency, and a second clock generating circuit selected by the second pumping control circuit to drive the other ends of the capacitors of the charge transfer circuit with a variable clock frequency.