【摘要】 分析了传统CMOS带隙基准源电路中三极管VBE电流随温度变化的二阶非线性效应,提出了一种对PTAT二阶温度进行补偿的方法,并在此基础上设计了一个高精度的带隙基准源电路。该电路采用SMIC 0.18μm CMOS工艺实现,具有良好的温度系数和电源抑制比。CadenceSpectre仿真结果表明,该电路在-40~140℃的温度系数为7.7×10-6/℃,低频时的电源抑制比可达-76 dB,基准源电路的供电电压范围为2~4.5 V。更多还原

【Abstract】 The second-order nonlinear effect of the transistor VBE current varying with temperature in the conventional CMOS bandgap reference was analyzed.A curvature compensation method for the proportion to absolute temperature(PTAT) was proposed and a high precision CMOS bandgap reference based on this method was designed.The bandgap referebce was implemented in SMIC 0.18 μm CMOS technology,which had a good temperature coefficient(TC)and a low power supply rejection ration(PSRR).Cadence Spectre simulation result shows that the circuit has an accuracy of 7.7×10-6/℃ at-40 to 140 ℃ and a power supply rejection ration of-76 dB at low frequency.The circuit can operate at the range from 2 to 4.5 V.更多还原