A low noise high efficiency buck DC-DC converter with sigma-delta modulation  

作　　者：蔡曙江 皮常明 严伟 李文宏 

机构地区：[1]State Key Laboratory of ASIC & Systems,Fudan University

出　　处：《Journal of Semiconductors》2011年第7期81-88,共8页半导体学报（英文版）

基　　金：Project supported by the National High Technology Research and Development Program of China(No.2009AA011607)

摘　　要：Some research efforts to improve the efficiency and noise performance of buck DC-DC converters are explored.A carefully designed power MOSFET driver,including a dead time controller,discontinuous current mode（DCM） controller and gate width controller,is proposed to improve efficiency.Instead of PWM modulation, sigma-delta modulation is introduced into the feedback loop of the converter to move out the clock-referred harmonic spike.The proposed converter has been designed and fabricated by a 0.35μm CMOS process.Measured results show that the peak efficiency of the converter can reach 93%and sigma-delta modulation suppresses the harmonic spike by 30 dB over PWM modulation.Some research efforts to improve the efficiency and noise performance of buck DC-DC converters are explored.A carefully designed power MOSFET driver,including a dead time controller,discontinuous current mode（DCM） controller and gate width controller,is proposed to improve efficiency.Instead of PWM modulation, sigma-delta modulation is introduced into the feedback loop of the converter to move out the clock-referred harmonic spike.The proposed converter has been designed and fabricated by a 0.35μm CMOS process.Measured results show that the peak efficiency of the converter can reach 93%and sigma-delta modulation suppresses the harmonic spike by 30 dB over PWM modulation.

关 键 词：buck DC-DC converter PWM modulation sigma-delta modulation DCM dead time control width control current sensing 

分 类 号：TN792[电子电信—电路与系统]