一种带2阶温度补偿的负反馈箝位CMOS基准电压源

A Negative Feedback Clamp CMOS Bandgap Voltage Reference with 2nd Order Temperature Compensation

根据带隙基准电压源工作原理,设计了一种带2阶温度补偿的负反馈箝位CMOS基准电压源。不同于带放大电路的带隙基准电压源,该基准电压源不会受到失调的影响,采用的负反馈箝位技术使电路输出更稳定。加入了高阶补偿电路,改善了带隙基准电压源的温漂特性。电路输出阻抗的增大有效提高了电源抑制比。基于0.18μm CMOS工艺,采用Cadence Spectre软件对该电路进行了仿真,电源电压为2V,在-40℃110℃温度范围内温度系数为4.199×10^(-6)/℃,输出基准电压为1.308 V,低频下电源抑制比为78.66 dB,功耗为120μW,总输出噪声为0.12mV/(Hz)^(1/2)。

A negative feedback clamp CMOS bandgap reference with 2nd order temperature compensation technique was designed on the basis of bandgap reference＇s principle.Different from the bandgap reference with an operational amplifier which was easily affected by the offset,the negative feedback clamp technique enabled the output more stable.The 2nd order temperature compensation technique had improved the temperature characteristics of the existing circuits.Also,a high output resistance had improved the power supply rejection ratio.The circuit was designed in a 0.18μm CMOS process,and it was simulated with the Cadence Spectre tools.The simulation results showed that the bandgap reference had a temperature coefficient below 4.199×10-（-6）/℃,and an output reference voltage of 1.308 Vwhen the temperature varied from -40℃ to 110℃and the supply voltage was 2 V.At low frequencies,the PSRR was 78.66 dB.The power consumption was 120μW,and the total output noise was 0.12 mV/（Hz）-（1/2）.