2099 - A Bootstrapless KY-S-Hybrid Buck-Boost Converter with Full Range iLs Reduction and 400% Line Transient Response Acceleration for AI-Mobile Application

Wednesday, March 19, 2025

8:30 AM – 8:50 AM ET

Location: Level Three, A311

Technical Lecture Presenter(s)

Chuan-En Chang (he/him/his)

National Taiwan University

Presentation Paper

Co-Author(s)

Hao-Ran Huang

National Taiwan University
Cheng-Ta Chuang (he/him/his)

National Taiwan University
CT

Chieh-Ju Tsai (he/him/his)

National Taiwan University NTU
CC

Ching-Jan Chen

National Taiwan University NTU

This digest introduces a hybrid buck-boost converter that combines KY-boost converter with S-hybrid converter for AI mobile application. The proposed converter reduces inductor current by over 23% relative to the output load current across the entire conversion range, thereby optimizing efficiency. It also utilizes a bootstrapless driving strategy, eliminating the need for additional off-chip capacitors and enhancing power density. By reducing the inductor current, a compact 0805 SMD inductor with a 57 mOhm DCR is sufficient, which substantially minimizes the converter board area. Furthermore, a generalized VIN-feedforward control method is implemented to reduce line transient output voltage deviation by 400% compared to conventional control schemes. The converter has been fabricated using 180 nm BCD process, achieving a simulated peak efficiency of 95.5%.