A microchip (300) for driving a resonant circuit, wherein the resonant circuit is an inductance (L) capacitance (C) circuit (LC tank), an antenna or a piezoelectric transducer, and wherein the microchip (300) is a single unit which includes a plurality of interconnected embedded components and subsystems including at least an oscillator (315), a pulse width modulation (PWM) signal generator subsystem (329), an analogue to digital converter (ADC) subsystem (318) and a digital to analogue converter (DAC) subsystem (327).