Capacitive-coupled current sensing and Auto-ranging slope compensation for current mode SMPS with wide supply and frequency range

Author

Herzer, Stefan ; Kulkarni, Sumeet ; Jankowski, Maciej ; Neidhardt, Jochen ; Wicht, Bernhard

Author_Institution

Texas Instrum., Freising, Germany

fYear

2009

fDate

14-18 Sept. 2009

Firstpage

140

Lastpage

143

Abstract

Techniques for high impedance current sensing and slope compensation, common challenges for current mode switched mode power supplies (SMPS), are presented. DCR sensing, limited by conventional low impedance sensing techniques, is thus possible, enabling power efficiency gains. Auto-ranging slope compensation based on a multiplication of input voltage V_IN and switching frequency f_sw allows for truer current mode operation and superior line transient response for a wide range of V_IN and f_sw. The techniques are demonstrated in an automotive-class 60 V V_IN buck controller at 150-600 kHz in a 0.35 mum BiCMOS technology. Offset error <3 mV over 0-10 V and single-cycle stable current loop response are measured.

Keywords

BiCMOS integrated circuits; current-mode circuits; switched mode power supplies; BiCMOS; DCR sensing; auto-ranging slope compensation; buck controller; capacitive-coupled current sensing; current mode switched mode power supplies; frequency 150 kHz to 600 kHz; high impedance current sensing; size 0.35 mum; voltage 0 V to 10 V; voltage 60 V; Buck converters; Control systems; Impedance; Inductors; Instruments; Optical character recognition software; Switched-mode power supply; Switching frequency; Transient response; Voltage;

fLanguage

English

Publisher

ieee

Conference_Titel

ESSCIRC, 2009. ESSCIRC '09. Proceedings of

Conference_Location

Athens

ISSN

1930-8833

Print_ISBN

978-1-4244-4354-3

Type

conf

DOI

10.1109/ESSCIRC.2009.5326034

Filename

5326034