Charge transfer circuit and method

The disclosure relates to a charge transfer circuit and method. The charge transfer circuit comprises: a first capacitor; a second capacitor; a MOS (metal oxide semiconductor) transistor; and an operational amplifier, wherein the first capacitor is configured to couple to the second capacitor via the MOS transistor; the operational amplifier is configured to receive a voltage at the first capacitor and output a control voltage; and the MOS transistor is configured to be controlled by the control voltage.