A high efficiency dual-mode buck converter IC for portable applications

作者：Liou Wan Rone^*; Yeh Mei Ling; Kuo Yueh Lung

来源：IEEE Transactions on Power Electronics, 2008, 23(2): 667-677.

DOI：10.1109/TPEL.2007.915047

• buck converter
• dual-mode converter
• integrated power management
• pulse-frequency modulation (PFM)
• pulsewidth modulation (PWM)

This paper presents the design of a novel wide output current range dual-mode dc to dc step-down (Buck) switching regulator/converter. The converter can adaptively switch between pulsewidth modulation (PWM) and pulse-frequency modulation (PFM) both with very high conversion efficiency. Under light load condition the converter enters PFM mode. The function of closing internal idle circuits is implemented to save unnecessary switching losses. The converter can be switched to PWM mode when the load current is greater than 100 mA. Soft start operation is designed to eliminate the excess large current at the start up of the regulator. The chip has been fabricated with a TSMC 2P4M 0.35 mu m polycide CMOS process. The range of the operation voltage is from 2.7 to 5 V, which is suitable for single-cell lithium-ion battery supply applications. The maximum conversion efficiency is 95 % at 50 mA load current. Above 85 % conversion efficiency can be reached for load current from 3 to 460 mA.

• 出版日期2008-3
• 单位中国科学院电工研究所