Design of a Digital Controller for Multi-phase Voltage Regulator Applications

A digital controller for a two-phase interleaved voltage regulator is presented in this thesis. To begin, the small-signal model is derived using state-space averaging method. Based on the small-signal model, the design of the compensator is accomplished through the pole-zero cancellation method. The control scheme is set at voltage mode, and the inductor current is sensed to achieve Gain Scheduling function. A lookup table is established so the parameters of the compensator can be adjusted for different loading conditions— so that the dynamic response can be enhanced. In addition, as long as the auto phase shedding technique is used, the operating phase number can be determined according to the loading condition, and the light load efficiency will be improved finally.he function of the designed digital controller is simulated and confirmed by using Matlab®/Simulink®.A digital controller for a 12V-to-1.2V two-phase interleaved voltage regulator is implemented using an FPGA(Field Programmable Gateway Array) board and the experimental results demonstrate the proposed controller design.