Patent ID: 8326255

Claim:
An electronic apparatus having an input device connected by wires, and a biasing arrangement, wherein the biasing arrangement comprises a bias signal generator arranged to provide a bias voltage and a reference voltage; a flying capacitor circuitry having a first set of switches connected to said bias signal generator to selectively connecting and disconnecting the bias voltage and reference voltage, respectively, over a capacitor of the flying capacitor circuitry, and the flying capacitor circuitry further having a second set of switches to selectively connecting and disconnecting the voltage over the capacitor to output terminals of the flying capacitor circuitry, wherein the first and second sets of switches are not both in a connecting state at any time; and a wired connection between the output terminals of the flying capacitor circuitry and terminals of the input device of the apparatus, wherein the input device comprises a biasing resistor; an analog input arrangement; and a signal output, wherein the biasing resistor and the analog input arrangement are connected in series between the terminals of the input device, and the signal output is connected such that the alternating voltage over the biasing resistor is provided as an output signal.