一种高阶曲率补偿带隙基准的原理与实现

基于指数型和二阶曲率补偿技术,设计了一个高阶曲率补偿带隙基准.在电路结构上采用电流镜和负反馈回路代替运放反馈回路,不仅避免了运放的失调电压所引起的输出误差和温漂问题,而且使得电路相对简单,更适于电路系统集成.;利用二阶曲率补偿和双极晶体管的电流增益β随温度成指数型变化的规律,对输出电压温度特性进行补偿,提高了的温度稳定性.基于0.6μm BiCMOS工艺设计了基准电路和版图.仿真、测试结果表明:基准在ΔV=2.8V的电源电压幅度范围下,具有0.08mV/V的电源抑制特性.在-55～125℃的范围内Vref的温度系数为5×10-6/℃.

Principle and Realization of a High-order Curvature-Compensated Bandgap Voltage Veference

A high-order curvature-compensated bandgap reference,which based on an exponential curvature compensation and second-order curvature compensation technique,is presented in this paper.In this work,current mirror and negative feedback loop instead of op-amp feedback loop,this approach not only eliminate the output voltage error and temperature drift which is caused by input offset voltage,but also make the circuit is much simple and more conducive to integration;Using second order curvature compensation and the characteristics of the temperature dependency of β is an exponential function of temperature,achieving the good output temperature characteristics.The circuit and layout is implemented in 0.6μm BiCMOS process,and the simulation results show that: Under the condition of ΔV=2.7 V wide input voltage range,it possesses the power supply rejected characteristic of 0.08 mV/V;temperature coefficient of the voltage reference is 5 ×10-6/ ℃ in a temperature range from-55~125 ℃.