A 1500mA, 10MHz on-time controlled buck converter with ripple compensation and efficiency optimization

Author

Lu, Danzhu ; Yu, Jiale ; Hong, Zhiliang ; Mao, Jingwen ; Zhao, Hui

Author_Institution

State Key Lab. of ASIC & Syst., Fudan Univ., Shanghai, China

fYear

2012

fDate

5-9 Feb. 2012

Firstpage

1232

Lastpage

1237

Abstract

A 10MHz self-adaptive on-time controlled buck DC-DC converter with optimized efficiency over full load range is presented. A low-cost passive ripple compensation scheme (PRC) and a self-adaptive on-time generator (SAOTG) are proposed to solve the system stability and frequency variation problem. Meanwhile automatic power transistor sizing (APTS) technique is used to improve the overall efficiency especially in heavy load. The converter has been implemented in 2P4M 0.35μm CMOS process. The measurement results show that the output ripple is smaller than 10mV and the overshoot of load transient response is realized as small as 8mV @ 200mA step. With APTS technique in ultra heavy load and PFM control in light load, the efficiency keeps over 81% for load range from 20mA to 1500mA and the peak efficiency reaches 88.43%.

Keywords

CMOS integrated circuits; DC-AC power convertors; circuit optimisation; 2P4M 0.35μm CMOS process; PFM control; automatic power transistor sizing technique; current 1500 mA; efficiency optimization; frequency 10 MHz; load transient response; low-cost passive ripple compensation scheme; ripple compensation; self-adaptive on-time controlled buck DC-DC converter; self-adaptive on-time generator; size 0.35 mum; Capacitors; Circuit stability; Inductors; Mathematical model; Stability analysis; Switching frequency; Voltage control;

fLanguage

English

Publisher

ieee

Conference_Titel

Applied Power Electronics Conference and Exposition (APEC), 2012 Twenty-Seventh Annual IEEE

Conference_Location

Orlando, FL

Print_ISBN

978-1-4577-1215-9

Electronic_ISBN

978-1-4577-1214-2

Type

conf

DOI

10.1109/APEC.2012.6165976

Filename

6165976