Based on sectional compensation principle and that the drain current of the MOS transistor is squared relationship function of the overdrive voltage,the design proposes a novel second-order compensation structure.Just introducing a current which is a square relation with temperature,both compensates the reference voltage for the low temperature stage and the high temperature stage,greatly improving the stability of the reference voltage source varying with temperature.By using 0.5 μm BCD process to simulate circuit,the results show that the output voltage is 1.24 V,and when the temperature range from-35 ℃ to 135 ℃,the temperature coefficient is 2.82 ppm/℃.And at low frequencies,power supply rejection ratio is 75.6 dB.%基于分段补偿原理和MOS管的漏极电流是过驱动电压的平方关系函数,提出了一种新颖的二阶补偿结构,仅引入一股与温度成平方关系的电流,既补偿了低温阶段的基准电压,又补偿了高温阶段的基准电压,大大提高了基准电压源随温度变化的稳定性.采用0.5 μm BCD工艺对电路进行仿真,结果表明,输出电压为1.24 V,温度范围在-35℃～135℃时,温度系数为2.82 ppm/℃；在低频时,电源抑制比达到了75.6 dB.
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