【摘要】 这篇文章提出了一种低电源电压高温度稳定性的带隙基准源。这种基准源主要思路是将输出基准电压反馈回曲率补偿回路,从而建立了一个闭环反馈回路。在这个闭环回路中,一方面,输出电压的温度系数越低,补偿电路就可以产生更准确地补偿电流,从而更加完全的抵消掉具有温度依赖的对数项;另一方面,如果补偿电路将对数项抵消得更彻底,输出电压的温度系数就会更低,这就形成了一种静态的正反馈。因而通过不断的调节补偿电阻,可以完全抵消掉对数项,实现高温度稳定性的基准源。同时利用电平移位技术为基准源设计了一个适合低电压工作的运算放大器。基于标准的0.18μmCMOS工艺设计了一种基准源电路。仿真结果表明这种基准源可以工作在电源电压从0.8V到1.8V,输出基准电压Vref的电压偏差只有0.87mV/V,在-20到80度温度范围内,Vref的温度系数为0.63ppm/oC。更多还原

【Abstract】 A new low-voltage CMOS bandgap reference(BGR) which achieves high temperature stability is proposed.It feeds back the output voltage to the curvature compensation circuit which constitutes a closed loop circuit.In the closed loop,the smaller of temperature coefficient(TC) of output voltage is,the better our curvature compensation circuit could counteract the logarithmic term.On the other hand,the better our curvature compensation circuit counteracts the logarithmic term,the smaller TC of output voltage could be.So we could repeatedly regulate the compensation resistors to improve the temperature stability of BGR.Finally,temperature stability of BGR becomes very high.Meanwhile a low voltage OTA is designed with level shifter.The circuit is designed with a standard 0.18μm CMOS technology.The simulated result shows that the BGR can operate from 0.8V to 1.8V.The temperature coefficient and line regulation are 0.63ppm/oC(-20 to 80 oC) and 0.87 mV/V respectively.更多还原