Signal amplifier

A method of amplifying an input signal, the method comprising:

• providing a network of switches between an input port, an output port and a ground port, the network of switches being arranged to form a power converter coupled to a H-bridge circuit, wherein the power converter comprises a flying capacitor and an inductor;
• the power converter being adapted to receive an input voltage from an input voltage supply and to provide a converted voltage, and the H-bridge circuit being adapted to receive the converted voltage and to apply an output modulated voltage to a load;
• providing a driver to operate the H-bridge circuit in a plurality of states for providing the output modulated voltage, the driver being adapted to drive the network of switches in a neutral state, a first state and a second state;
• wherein in the neutral state no voltage is applied to the load;
• wherein in the first state, the input voltage supply and the inductor are serially coupled and wherein the flying capacitor is coupled in parallel with the serially coupled input voltage supply and inductor;
• and
• wherein in the second state, the flying capacitor is coupled in series with at least one of the input voltage supply and the inductor.