宽温度范围高精度带隙基准电压源的设计

Design of a Bandgap Voltage Reference with Wide Temperature Range and High Precision

为了满足市场对宽温度范围、高精度带隙基准电压源的需求,本文设计制作了一种新型带隙基准电压电路。设计采用多点曲率补偿技术,在温度较低时采用指数频率补偿,高温时采用亚阈值指数曲率补偿。采用电压-电流转换器对分段补偿电流在输出端进行整合,进而在-55~150℃的温度范围内进行补偿,得到低温度系数的基准电压。设计的电路采用CSMC 0.5μm CMOS工艺验证,结果表明:5V电源电压下,输出1.25V的基准电压;在-55~150℃的温度范围内温度系数为2.5×10^(-6)/℃,在低频时,PSRR为-66dB。带隙基准电压源芯片面积为0.40mm×0.45mm。

In order to satisfy the requirements of wide temperature range and high precision,a novel bandgap voltage reference(BGR)was successfully designed and fabricated in this paper.High-order curvature correction was accomplished by a novel multiple-point curvature compensation technique,achieving exponential curvature compensation(ECC)in lower temperature range,and sub-threshold exponential curvature compensation(SECC)in higher temperature range.Thus a wide temperature range BGR with low TC was obtained,while a V-I convertor was employed to add these current into the output of the BGR,then a voltage reference with low temperature coefficient was realized in the temperature range of-55~150℃.Proposed BGR was implemented with the CSMC 0.5μm CMOS process,and the result showed that the proposed circuit could achieve 2.5×10^(-6)/℃in the range of-55℃~150℃,and 1.25 Voutput voltage at 5Vsupply voltage.Besides,the power supply rejection ratio was-66 dB when the frequency was low.The chip area of the BGR was 0.40mm×0.45 mm.