A High-Speed Synchronous Rectifier With Improved Dead Time Compensation and Suitable for High-Voltage Applications

• Published in: IEEE transactions on power electronics 2024-01, Vol.39 (1), p.25-29
• Main Authors: Chen, Minggang, Li, Yongjia, Shi, Jiawei, Ding, Song, Fang, Zhongyuan, Xu, Shen, Qian, Qinsong, Sun, Weifeng
• Format: Article
• Language: English
• Subjects: <named-content xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" content-type="math" xlink:type="simple"> <inline-formula> <tex-math notation="LaTeX"> V_DS</tex-math> </inline-formula> </named-content>-sensing; Buck converters; Compensation; Delay; Delays; Double clamp zero voltage switching (DCZVS) buck–boost converter; High speed; High voltages; high-voltage blocking; High-voltage techniques; Inductance; Integrated circuits; Parasitics (electronics); Power supplies; Power supply circuits; Propagation delay; Rectifiers; Switching; Synchronous machines; synchronous rectifier (SR); Voltage; Zero voltage switching
• ISSN: 0885-8993; 1941-0107
• DOI: 10.1109/TPEL.2023.3312132

V DS (drain-source voltage)-based synchronous rectifiers (SRs) are widely used due to their simplicity and low cost. However, there are still three obvious issues. 1) The premature turn- off caused by parasitic inductance under high frequency. 2) The turn- on propagation delay is typically tens of nanoseconds. 3) Commercial SRs usually have a limited V DS rating of about 200 V. To solve the above problems, a high-speed SR (including a customized SR IC and a peripheral circuit) is proposed. A high-speed comparator together with a slope detection circuit is proposed to reduce the turn- on delay, and the proposed fully integrated SR IC is implemented in a 1- μ m bipolar process with a die area of 1.47 × 1.98 mm 2 . The peripheral circuit contains the improved dead time compensation circuit, the self-driven high-voltage isolation circuit, and the power supply circuit for SR IC, and the component count is reduced by device reuse. In a 200-W Double clamp zero voltage switching (DCZVS) buck-boost converter prototype, the proposed SR can achieve a switching frequency of more than 700 kHz with minimal dead time, the turn- on propagation delay including peripheral circuits and SR IC is reduced to 8.1 ns, the isolated drain-source voltage is limited to within 10 V, and the peak efficiency is 93.6%.