Open AccessFast‐response full‐wave inductor current sensor for 10 MHz buck converter
Author(s) -
Zhou Yong,
Zheng Yanqi,
Leung Ka Nang
Publication year - 2018
Publication title -
electronics letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.375
H-Index - 146
ISSN - 1350-911X
DOI - 10.1049/el.2017.4492
Subject(s) - inductor , bandwidth (computing) , buck converter , current sensor , voltage , current (fluid) , amplifier , settling time , electrical engineering , electronic engineering , materials science , engineering , telecommunications , step response , control engineering
A sense‐FET‐based inductor current sensor for a buck converter operating in 10 MHz switching frequency is reported in this Letter. The proposed sensor utilises an adaptive g m ‐boosting amplifier to maintain stable current sensing loop gain and bandwidth over a wide range of load current. Moreover, a mirrored source‐degeneration output stage is introduced to further eliminate the bandwidth variation by loading change and achieves full‐wave current sensing with smooth transition between the sensed peak and valley currents as the inductor is energised and de‐energised. Simulation results show high sensing accuracy better than 96.8% with inductor current varying from 200 mA to 2 A. Furthermore, the settling time is <6 ns during the state transition between peak and valley current sensing with low‐voltage spikes.