A mixed-signal control for VRM applications

This paper proposes a mixed-signal control for Voltage Regulated Modules (VRMs), which is based on a digital voltage loop and a peak-modulator digitally controlled by a low-resolution digital-to-analog converter (DAC). Improvement in the dynamic response and elimination of static quantization effects are obtained performing the peak-modulation on a weighted sum of output voltage and inductor current. The control features good dynamic performance, fixed switching frequency, small quantization effects, and low-complexity. Simulation and experimental results on a three-phase interleaved synchronous buck VRM confirm the performance of the proposed solution