A novel DPWM structure with high time resolution and low clock frequency

Abstract

This paper presents a novel digital pulse width modulator (DPWM) structure with higher time resolution and lower input clock frequency, which is especially suitable for high frequency digitally controlled DC-DC switching converters. For the proposed DPWM, two multi-phase clock arrays are generated which have relatively close frequencies, and the time-inserting method is also utilized. The FPGA based simulation results show that, the proposed DPWM can achieve the time resolution of around 30ps and the equivalent 12-bits precision when the input dual-clock frequencies are 100MHz and 105MHz at 5MHz switching frequency.