Integrated lossless load current sensing method for buck–boost DC–DC converters

Author

Yanzhao Ma

Author_Institution

Sch. of Software & Microelectron., Northwestern Polytech. Univ., Xi´an, China

Volume

51

Issue

1

fYear

2015

fDate

1 8 2015

Firstpage

88

Lastpage

90

Abstract

An integrated lossless load current sensing method for buck-boost DC-DC converters is presented. The load current is detected by sensing the average current flowing through the power transistor connected between the inductor and the output capacitor. The circuit is almost independent of voltage and temperature by using a sense resistor method. A second-order on-chip lowpass filter is adopted to average the sensed voltage. The buck-boost converter could automatically switch between heavy and light load modes with a fixed switching current for different input and output voltages.

Keywords

DC-DC power convertors; electric current measurement; low-pass filters; resistors; buck-boost DC-DC converters; fixed switching current; heavy load modes; inductor; input voltages; integrated lossless load current sensing method; light load modes; load current detection; output capacitor; output voltages; power transistor; second-order on-chip low-pass filter; sense resistor method;

fLanguage

English

Journal_Title

Electronics Letters

Publisher

iet

ISSN

0013-5194

Type

jour

DOI

10.1049/el.2014.3439

Filename

7006833