Buffer device for switched capacitance circuit

An integrated electric circuit comprising:

• at least one source of an input voltage;
• a switched capacitance user circuit to receive the input voltage;
• and
• a buffer device coupled between the source and the user circuit, wherein the buffer device comprises:
• a buffer having an output for an output voltage dependent upon an input voltage that can be supplied by a source to the buffer device;
• a capacitive switching component that can be switched between a first and second condition in which it is connected, respectively, to the source to take on the input voltage and to the buffer to transfer onto the output the input voltage;
• the capacitive switching component provided with a terminal having an associated stray capacitance;
• and
• a charging and discharging device connected to the terminal and configured to pre-charge the stray capacitance on the capacitive switching component at a reference voltage before taking on the second condition, and to discharge the stray capacitance before taking on the first condition, keeping an electrical charge of the capacitive discharge component substantially constant in the first and second conditions.