Open AccessFully integrated high‐efficiency high step‐down ratio DC–DC buck converter with predictive over‐current protection scheme
Author(s) -
Wang Langyuan,
Zhao Menglian,
Wu Xiaobo,
Gong Xiaohan,
Yang Liuqing
Publication year - 2017
Publication title -
iet power electronics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.637
H-Index - 77
eISSN - 1755-4543
pISSN - 1755-4535
DOI - 10.1049/iet-pel.2017.0087
Subject(s) - voltage , current (fluid) , buck converter , transistor , electronic engineering , electronic circuit , materials science , low voltage , electrical engineering , computer science , engineering
A high‐efficiency fully integrated 36 V–3 A stepping down DC–DC converter with high step‐down ratio and predictive over‐current protection scheme is introduced. To achieve high‐voltage conversion ratio, emulated current mode and dedicated current sensing circuits were involved. A novel predictive over‐current scheme is proposed to overcome inherent lack of emulated current‐mode control and provide fast response to over‐current events. In addition, due to N‐type field effect transistor (NFET) was adopted to improve efficiency, a floating rail regulator is presented to generate bootstrapped voltage for driver stage. The proposed converter was simulated and fabricated in 0.18 μm bipolar‐complementary metal–oxide–semiconductor (MOS)‐double‐diffused MOS process. Experimental results show the features work well, and with 35 ns minimum on‐time, this converter can convert up to 36 V input voltage to 1.8 V at 1 MHz switching frequency with single stage and compact solution. Measured peak efficiency is 89.5% and over 80% efficiency for 3 A output current is realised as well.