A multimode, switching-surface controlled dc-dc converter with improved light-load efficiency

Author

Ueno, Tomohiro ; Itakura, T.

fYear

2012

fDate

15-20 Sept. 2012

Firstpage

1078

Lastpage

1081

Abstract

This paper describes a switching-surface (SS) controlled dc-dc converter that operates in PFM (pulse-frequency modulation) mode. SS control in continuous-current mode (CCM) has, as an essential property, fast response to load transient. To realize the SS control, a simple circuit that generates a switching function by using only one operational amplifier is proposed. In addition to the CCM operation, PFM mode operation is implemented to enhance efficiency at light load. The proposed converter seamlessly switches between CCM and PFM modes depending on load current. Experimental results for a 1 A, 5 to 1.2 V buck converter are shown. The response to a load transient is nearly optimal, limited by only the power-stage components. By using the proposed PFM mode, efficiency is improved by 30% at an output of 10 mA.

Keywords

DC-DC power convertors; pulse frequency modulation; CCM operation; PFM mode operation; continuous-current mode; light-load efficiency; multimode switching-surface controlled dc-dc converter; pulse-frequency modulation; switching function; Capacitors; Integrated circuits; Semiconductor device measurement; Switches; Transient analysis; Voltage control;

fLanguage

English

Publisher

ieee

Conference_Titel

Energy Conversion Congress and Exposition (ECCE), 2012 IEEE

Conference_Location

Raleigh, NC

Print_ISBN

978-1-4673-0802-1

Electronic_ISBN

978-1-4673-0801-4

Type

conf

DOI

10.1109/ECCE.2012.6342699

Filename

6342699