A 400-to-12 V Fully Integrated Switched-Capacitor DC-DC Converter Achieving 119 mW/mm2 at 63.6 % Efficiency

High-voltage power sources, such as the mains (up to 240 VRMS) and high-voltage batteries in electric cars (e.g., 400 V), are omnipresent. In contrast, low-power applications like loT, smart homes, and control in electric vehicles need low supply voltages [1]. Bridging this voltage gap requires power converters with high input voltages and large conversion steps. Furthermore, complete integration of these converters enables significant cost reduction and makes the system more reliable and compact. Recent developments confirm this integration trend for large conversion steps, as bulky transformers in power modules are replaced by smaller and fewer external components [1], [2]. However, complete integration of their large off-chip inductors would suffer from a low quality factor, and for large conversions steps, these converters depend on very low duty cycles. The switched-capacitor converter (SCC) is a better candidate since it is easily integrated while operating at a 50 % duty cycle regardless of the conversion step. In addition, it is often used as the second stage in fully integrated AC-DC converters to improve performance [3]. However, state-of-the-art fully integrated SCCs only handle input voltages up to 42 V [3], [4]. In addition, they lack performance due to increased parasitics and component degradation at high voltages.