A charge pump circuit comprises:
- a charge pump (CP) with an input voltage (V R ) and an output voltage (V CP ) which is a multiple N of the input voltage (V R ), the charge pump (CP) having a clock input (CLK),
- an input stage (10) with a reference terminal for receiving a reference voltage (V REF ) and an output terminal coupled to the charge pump (CP) for applying the input voltage (V R ) to the charge pump (CP), and
- at least one output capacitance (C OUT ) coupled (14, 16) to the charge pump (CP) and chargeable to an output voltage (V OUT ) of the circuit.
The circuit comprises:
- a feedback network (14, 16) comprising a first feedback loop (14) for feeding back the output voltage (V CP ) of the charge pump (CP) towards the input of the input stage (10) and a second feedback loop (16a, 16b, 16c) for maintaining a fixed offset between the output voltage (V CP ) of the charge pump (CP) and the output voltage (V OUT ) of the circuit, and/or
- the output capacitance (C OUT ) being divided between two output capacitors (α.C OUT ; (1-α).C OUT ) with a switch (S1) set between the two capacitors and driven by a driver unit (20) coupled to the clock input (CLK) of the charge pump (CP), with the switch (S1) which is opened at switching edges of the clock signal (CLK) at the clock input (CLK) of the charge pump (CP).