DC-DC conversion techniques for low-voltage power supplies

Abstract

This paper describes two DC-DC conversion techniques suitable for low-voltage mobile applications. Converters using the first technique realize high efficiency under light-load conditions by having an architecture with a simple common-source amplifier and a low-power differential amplifier. The measured efficiency of the first type of converter is 67% at an output current of 23 μA. A one-shot technique in the second type of converter reduces output-voltage fluctuation. A predetermined current is injected into the output capacitor when a load transient is detected by observing the capacitor current. This technique reduces overshoot voltage by 68% at a high-to-low load transient.