Charge pump circuit

Abstract

Provided is a charge pump circuit for which optimization based on used elements is sufficient from the viewpoints of current consumption and boosting efficiency. The charge pump circuit includes a plurality of pump cells connected in series, at least one stage number changing circuit, and a power supply voltage detection circuit. The plurality of pump cells include a first stage pump cell formed of a low-voltage element configured to receive an input voltage, and at least one remaining pump cell formed of a high-voltage element. The remaining pump cells include a final stage pump cell connected to an output terminal. The stage number changing circuits are connected in parallel to the remaining pump cells. The power supply voltage detection circuit is configured to control the remaining pump cells and the stage number changing circuit so as to selectively stop and bypass a corresponding pump cell of the remaining pump cells in accordance with a voltage range of the detected input voltage.

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