Patent ID: 8207785

Claim:
A charge pump circuit with improved reliability which generates an output voltage though amplifying an input voltage, the charge pump circuit comprising: a first charging capacitor which is charged by the input voltage or outputs its stored charges according to a voltage level of a first node; a pumping capacitor coupled between an input end and an output end of the charge pump circuit, wherein the pumping capacitor receives the charges from the first charging capacitor and provide the output voltage; a first constant voltage device coupled to the first charging capacitor and configured to provide a first bias voltage at the first node; a second constant voltage device coupled to the pumping capacitor and configured to maintain a voltage across the pumping capacitor at a second bias voltage; a first switch coupled to the first node and configured to control a signal transmission path between the first node and a third bias voltage according to a first clock signal, wherein the third bias voltage has a lower level than the first bias voltage; a first path-control device configured to control a signal transmission path between the input end of the charge pump circuit and the first charging capacitor; and a second path-control device configured to control a signal transmission path between the first charging capacitor and the pumping capacitor.