A Smart PWM Controller with Pulse Skipping and Flexible Power Distributive Order for Ultra-Wide Load Range Single Inductor Five Output Buck Converter

• Main Authors: Yen-Ru Chiang, 江彥儒
• Other Authors: Chung-Hsun Huang
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/41870560668168543432

碩士 === 國立中正大學 === 電機工程研究所 === 103 === In recent years, the rapid development of portable electronic products integrating a variety function blocks into a signle product has become a trend. The power management unit must be able to supply the voltage and current of each functional blocks needed. Single-inductor multiple-output DC-DC switching converter not only meet today's demand for multi-voltage but also greatly reduce the system cost and size. In order to improve the single-inductor multiple-output switching converter on the use of flexible product, which needs to have a wide load range of the converter output capabilities is necessary. However, different requirements of the load current and voltages between different output channels can cause cross-regulation problems and limit the converter output range. In this paper, the converter adopts power distribution control to achieve wide load range of output current capabilities. The proposed controller architecture with flexible order to solve operational problems cause by different load conditions and reduce the effects of cross-regulation between different output channels . The proposed single-inductor five output buck converter fabricated with TSMC 0.18μm CMOS process. The input voltage is 2.7V~3.63V and the output voltages are 2.0V, 1.8V, 1.6V, 1.4V and 1.2V, and the load current range for each output is 1mA ~ 850mA, the maximum conversion efficiency of converter reaches 85.09% (at Io1=Io2=Io3=Io4=Io5=40mA). Simulation results show that when Vo1 has load transient from 50mA to 850mA, the voltage variation caused by cross-regulation of Vo2~Vo5 is less then 21.66mV.