Patent ID: 6177828
Filing Date: 2001-01-23
Classification: G05F,G11C,H02M

Abstract:
A charge pump for a charge pump circuit, comprises:a timing controller that generates a plurality of pulse signals having a predetermined pulse width in accordance with at least one externally applied first control signal;first through fourth capacitors for carrying out a pumping operation in accordance with corresponding pulse signals outputted from the timing controller to provide first through fourth potentials at first through fourth output nodes, respectively;a booster circuit for receiving a corresponding number of pulse signals generated from the timing controller, carrying out a boosting operation to obtain a required level thereof, and halting the boosting operation in response to a second control signal;a first transistor for maintaining the first output node of the first capacitor at a first potential when power is turned on;a clamping circuit to clamp the first output node between at least one of (1) the first and fourth potentials and (2) the first and third potentials;a clipping circuit for clipping the applied supply voltage to a predetermined voltage, and maintaining at least one of the first and fourth output nodes respectively to the predetermined voltage in accordance with the clipped voltage;a transistor, responsive to the first potential, for maintaining the second output node to the applied supply voltage during an initial pumping; anda switch for transmitting the second potential to an output node in response to at least one of the third and fourth potentials.