一种用于负LDO稳压器的高精度带隙基准源

A High-Precision Bandgap Reference Source for Negative LDOs

介绍了一种高精度带隙基准电路结构。采用二阶曲率补偿技术,通过增加一正温度系数项,补偿电路中Vbe(T)展开的负温度系数对数项,改善了基准电压源的温度稳定性。应用该基准电路,设计了一个负输出低压差(LDO)线性稳压器,用高压BIPIC工艺进行流片。测试结果显示,该负LDO线性稳压器的温度系数为85 ppm/℃,线性调整率≤0.02%/V,负载调整率≤0.2%。

A high-precision bandgap reference circuit topology has been developed. Using 2nd-order curvature compensation technique, temperature performance of the voltage reference has been improved by compensating the negative temperature dependence of the logarithmic term in Vbr （T） with a positive term. A negative low drot-out linear regulator is designed with the bandgap reference, and implemented in high voltage BIPIC process. Test results show that the negative LDO has a temperature coefficient of 85 ppm/℃, a max line regulation of 0.02%/V and a max load regulation of 0.2 %.