Improved transient response of controllers by synchronizing the modulator with the load step: application to v2ic

Abstract

V2Ic is a ripple-based control with an excellent performance for load transients and reference voltage tracking because it exhibits a feedforward of the load current and the error of the output voltage. However, if V2Ic is modulated with constant frequency, constant on-time or constant off-time, its dynamic response is hindered by delays in the response. This paper proposes a technique that synchronizes the clock of the converter to initialize the duty cycle when a worst-case load transient occurs using the current through the output capacitor to detect load transients. It is exemplified on a V2Ic control but it is applicable to most of controllers as it only acts on the modulator.