用于开关电源的高精度多基准带隙电压源设计

Design of High-Precision Multi-Bandgap Voltage Reference Circuit for Switching Power Supply

带隙基准源是开关电源的重要组成部分。在对传统带隙基准源电路进行分析的基础上,结合曲率校正技术、高增益反馈技术和缓冲隔离技术,提出了一款应用于开关电源的高电源抑制比、低温漂系数和多基准输出新型基准源电路。基于0.5μm CMOS工艺,对电路进行仿真。结果表明,在-25℃～150℃范围内和典型(TT)工艺角下,设计的基准源温漂系数小于3×10-6/℃,PSRR为-78dB,可产生3V,1.2V,1V,0.2V四个基准输出电压。

Based on the analysis of conventional band-gap reference circuit,a novel multi-voltage band-gap reference source for switching power supply was proposed using curvature compensation,high power gain feedback and buffer isolation technologies.The circuit achieved a high power supply rejection ratio（PSRR） and low temperature drift coefficient.Simulation based on 0.5 μm CMOS technology at process corner TT,showed that,in the temperature range from-25 ℃ to 150 ℃,the multi-voltage reference circuit had a temperature drift coefficient less than 3×10-6/℃ and a PSRR of-78 dB,and it was capable of delivering four reference voltages：-3 V,1.2 V,1 V and 0.2 V.