Dynamic Width Controller for Switch Mode DC-DC Converter
Zhang Chun-hong①② Yang Hai-gang① Richard Shi③ Wei Yuan-feng① Yu Le① Chen Zhu-jia① Qu Xiao-gang①
①(Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, China) ②(University of Chinese Academy of Sciences, Beijing 100049, China) ③(Department of Electronic Engineering, University of Washington, Seattle WA9815, USA)
Abstract：A Dynamic Width Controller (DWC) for switch mode DC-DC converter is designed. Based on the comparison result of the sensed load current and the internal reference current, the controller can select the optimum switch width and drivers for the DC-DC converter according to the load current condition. The controller can improve the efficiency of DC-DC converter for high switching frequency and light load applications. The chip adopts a low power cost Voltage-Current Converter (VCC) to provide load current information for the DWC. To ensure the security of the chip’s performance, protection circuits are also integrated. The chip is simulated and fabricated under standard 0.35 μm CMOS process. The experiment results show that the proposed circuit can achieve dynamic switch width control for the DC-DC converter, and the maximum efficiency improvement is 6% for light load condition.
2013, Vol. 35 
