Abstract-This paper introduces the v 1 concept that explains how by only measuring the output voltage, designers have information about almost every signal of the power stage. Following the v 1 concept, it is explained how to design a traditional type-Ill voltage-mode control to behave like a current-mode control with near time-optimal response under load transients. This study is validated in simulations and experimentally on a 300-kHz buck converter.

Abstract-V2 I C 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 V 2 I C 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 V 2 I c control but it is applicable to most of controllers as it only acts on the modulator.Index Terms-Clock synchronization, dynamic voltage scaling, load transient, point of load, V 2 I C .

This study is related to the improvement of the output impedance of the buck converter by means of introducing an additional power path that virtually increases the output capacitance during transients. It is well known that in voltage regulation module applications, with wide load steps, voltage overshoots and undershoots may lead to undesired performance of the load. To solve this problem, high-bandwidth high-switchingfrequency power converters can be applied to reduce the transient time or a big output capacitor can be applied to reduce the output impedance. The first solution can degrade the efficiency by increasing switching losses of the MOSFETS, and the second solution is penalizing the cost and size of the output filter. The output impedance correction circuit, as presented here, is used to inject or extract a current n−1 times larger than the output capacitor current, thus virtually increasing n times the value of the output capacitance during the transients. This feature allows the usage of a low-frequency buck converter with smaller capacitor but satisfying the dynamic requirements.Index Terms-Additional energy path, output impedance, synchronous buck converter, virtual output capacitor.

Abstract-This paper proposes an optimization method to design the parameters of controls for power converters in order to achieve a very fast dynamic response while remaining stable and robust over the desired operation region. The proposed optimization algorithm is applied to different analog controls and is used to compare the dynamic response of the Voltage mode, V 2 and V 2 I C control for different cases in order to evaluate which control presents the best performance in terms of dynamic response and stability robustness to system tolerances.

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