Novel digital multi-phase duty cycle modulation methods for voltage regulators

For digitally controlled Voltage Regulator (VR), high resolution, high switching frequency digital pulse-width modulator (DPWM) is required. With conventional constant frequency modulation method, ultra high clock frequency is needed, which will consume unaffordable power. This paper proposes a pseudo-dither method based on digital constant on-time modulation to achieve high duty cycle resolution in multi-phase application without adding too much hardware cost. About 10 times higher improvement on resolution can be gained in VR application. Experiment results verify the proposed method.