一种高精度曲率补偿带隙基准电压源设计

摘要

According to the principle of bandgap reference voltage source,a bandgap reference voltage source for high-pre-cision second-order curvature compensation was designed based on CSMC 0.5 μm process. The temperature characteristic curve is compensated in high temperature zone by using the exponential relation between leakage current and grid voltage of a MOS-FET working in the sub-threshold region. A voltage reference source,whose output reference voltage is 2.5 V,was obtained by Spectre simulation. Its wiorking voltage range is 3.35~7.94 V,the power supply rejection ratio is -71.73 dB at 1 kHz. and the temperature coefficient is 7.003×10-6/℃ while temperature changes from -25 ℃ to 125 ℃.%根据带隙基准电压源的原理，基于CSMC 0.5μm工艺设计了一种高精度二阶曲率补偿带隙基准电压源。利用MOS管工作在亚阈值区时漏电流和栅极电压的指数关系，在高温段对温度特性曲线进行补偿。通过Spectre仿真，得到输出基准电压为2.5 V的电压基准源。工作电压范围为3.35~7.94 V，1 kHz时电源抑制比为-71.73 dB，温度从-25~125℃之间变化时温度系数为7.003×10-6℃-1。