Integrated MOS Bootstrap Circuit Based on 600V High-Voltage BCD Process

This paper presents an in-depth investigation of the bootstrap circuit for high-voltage gate driver chips, based on a $600 \mathrm{~V} 3 \mu \mathrm{~m}$ BCD process, with the objective of enhancing the overall performance of high-voltage integrated circuits (HVIC). Conventional bootstrap circuits suffer from issues such as poor reliability, low integration, and high costs. In response to these challenges, this work designs an integrated MOS bootstrap circuit to replace the conventional bootstrap diode scheme. Through the first HVIC chip tape-out, it was observed that the bootstrap voltage only reached 12 V, falling short of the expected 15V. To address this issue, the paper proposes a charge-pump boosted control MOS bootstrap circuit, which successfully resolves the insufficient charging problem in traditional bootstrap circuits.