Charge pump circuit

Abstract

This disclosure provides a charge pump circuit. The charge pump circuit for boosting positive voltage according to this disclosure includes one or more cascaded boost units and output units having the same structure. Each boost unit has a dual-branch structure with symmetrical upper and lower branches but reversed clock phases. By transmitting the high level stored in the secondary capacitor or the low level output from the previous stage to the gate of the current stage's transfer transistor to control its full conduction or complete turn-off, the problems of gate voltage drop and threshold voltage loss of the transfer transistor caused by charging from the previous stage node to the subsequent stage node in existing charge pump circuit structures are avoided. This effectively improves the charge transfer efficiency and boost capability of the charge pump circuit, reduces the operating power consumption of the charge pump circuit, and makes it suitable for lower power supply voltages. By reversing the charge pump circuit for boosting positive voltage according to this disclosure, a charge pump circuit for stepping down ground voltage or negative voltage can also be provided.

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