Patent ID: 8427126

Claim:
A digital pulse-width modulation (DPWM) control system comprising: a power stage for converting voltage comprising: an input voltage port; an output voltage port; and an input control port for receiving a DPWM control waveform; an error sampling block operatively coupled to the output voltage port of the power stage and comprising: an analog-to-digital converter; and an error comparison circuit; wherein the error sampling block is adapted to output a digitized error signal representing a voltage difference between the output voltage of the power stage and a reference voltage; a gain scheduling block adapted to apply a non-linear gain to the digitized error signal from the error comparison circuit to produce a gain-scheduled error signal; a compensator filter for filtering the gain-scheduled error signal; and a digital PWM module configured to receive the filtered gain-scheduled error signal and to output a DPWM control waveform that is operatively coupled to the input control port of the power stage; wherein the gain scheduling block is further adapted to apply a non-linear gain having a profile that: increases slowly with input amplitude for small input amplitudes; increases quickly with input amplitude for medium input amplitudes; and increases slowly with input amplitude for large input amplitudes.