A High-Voltage Dual-Input Buck Converter With Bidirectional Inductor Current for Triboelectric Energy-Harvesting Applications

This article presents a high-voltage (HV) dual-input buck converter with a bidirectional inductor current (IL) and a fully integrated maximum power point tracking circuit for triboelectric (TE) energy-harvesting applications. The proposed converter regulates HV inputs through a single shared inductor, and HV inputs can be isolated without using an additional HV protection circuit. In addition, the proposed diode-based HV sampling circuit can accomplish high ac voltage sampling and peak detection to perform the fractional open-circuit voltage method without any external components. Fabricated using a 180-nm bipolar-CMOS-DMOS (BCD) process, the proposed system with a self-manufactured polytetrafluroethylene (PTFE)based TE nanogenerator can regulate two HV inputs up to 70 V and achieve a power conversion efficiency of 84.7% and an endto-end efficiency of 75.6%, which are 30.2% and 22.7% better than prior work, respectively.