一种降压型开关电源芯片电路的研究与设计  

Research and Design of a Buck Switching Power Supply Chip Circuit

作　　者：刘财坤[1] 高加亭[1] 

机构地区：[1]中国电子科技集团公司第四十七研究所,沈阳110032

出　　处：《微处理机》2014年第1期80-84,共5页Microprocessors

摘　　要：设计了一款PWM控制模式降压式(buck)直流-直流转换器芯片。该芯片为电压反馈控制模式,内部补偿使得反馈控制有很好的线性和很快的负载响应而无需通过外部设计。芯片采用CMSC 0.5μm BCD工艺实现。PSPICE仿真结果表明,输出电压只有大约50mV的纹波,静态电流为3mA左右。输出电压在低于0.5V时,芯片具有短路降频功能,工作频率由81KHz降到23KHz左右,输出负载由0.2A跳变到2A时具有很好的负载调整率,大约为0.2%,转换效率可以达到85%以上。The key circuit of the buck switching power supply chip is designed in this paper, in which the voltage feedback control mode is adopted. The internal compensation is conducted to make good liner in feedback control and quick load respond without the external design. The chip is implemen- ted in CMSC＇s 0.5um BCD process. PSPICE simulation results show that the chip can realize short circuit drop frequency function by means of reducing operation frequency from 81KHz to 23KHz when output voltage is less than 0.5V. The conversion efficiency can be up to 85% and the regulation rate of the load is about 0.2% when output load directly changes from 0.2A to 2A.

关 键 词：降压式 电压模式反馈控制 短路降频 负载调整率 

分 类 号：TN46[电子电信—微电子学与固体电子学]