Monolithic 230-V RMS-to-12-VDC AC–DC Converter at 9 mW/mm 2 Enabled by a 31–325-V DC Input Range Capacitive Multi-Ratio DC–DC Converter Tuur

Abstract

This article introduces a fully integrated 230- Vrms-to-12-Vdc AC–DC converter implemented in a 180-nm high-voltage CMOS SOI technology. The primary block is a switched-capacitor dc–dc converter (SCC), which is reconfigured by parallelizing stages using low-voltage configuration switches. These configuration switches are connected between internally generated dc nodes that do not swing at the SCC switching frequency, thereby avoiding the periodic charging of the corre- sponding drain capacitances. An efficient pre-charging technique enables this SCC into the ac–dc converter without breaking down its low-voltage components. In addition to the SCC, a linear regulator is incorporated into the ac–dc converter, resulting in a 2× smaller capacitance to buffer the zero crossing. The design also features compact drivers and an efficient resettable capacitive voltage divider for input sensing. The measured power density is 9 mW/mm 2 at 55.1% efficiency, advancing the power density of fully integrated state-of-the-art ac–dc converters by >5000×.