曲率补偿低温漂带隙基准电压源设计

摘要

A low temperature drift bandgap reference source with curvature compensation was designed. The prototype was implemented with traditional amplifier clamping, two kinds of different section curvature compensation circuit were added to the circuit, node current subtracting was designed to generate a negative temperature coefficient compensation current in the low temperature phase, transistor conduction was controlled to generate a positive temperature coefficient compensation current in the high temperature phase, the curvature compensation for the reference voltage was achieved. Cascode structures were also introduced in this bandgap reference to improve the power supply rejection ratio (PSRR). Based on 0.18 µm TSMC process, the circuit was simulated with Cadence Spectre. Simulation results indicate that the output reference voltage is 1.241 V under the 3.3 V power supply. The bandgap reference voltage has a temperature coefficient of 3.02×10–6/℃ at –40–+125℃. The power supply rejection ratio (PSRR) is lower than –57 dB at low frequency.%设计了一种曲率补偿低温漂带隙基准电压源。采用放大器钳位的传统实现方式，在电路中加入两种不同的分段曲率补偿电路，低温阶段，设计节点电流相减产生一段负温度系数补偿电流，高温阶段，控制晶体三极管导通产生一段正温度系数补偿电流，实现了对基准电压曲率补偿，同时采用共源共栅结构以提高电路的电源抑制比。在0.18µm的TSMC工艺下，使用Cadence Spectre对电路进行仿真，仿真结果表明，在3.3 V的电源电压下，基准输出电压为1.241 V，在–40~+125℃范围内，基准电压的温度系数为3.02×10–6/℃，低频时电源抑制比(PSRR)低于–57 dB。