一种低失调轨到轨集成运算放大器的设计  

Design of a Rail-to-Rail Integrated Operational Amplifier with Low Offset

作　　者：刘国庆 孙婧雯 马奎 杨发顺 Liu Guoqing;Sun Jingwen;Ma Kui;Yang Fashun(College of Big Data and Information Engineering,Guizhou University,Guiyang 550025,China;Key Laboratory of Micro-Nano-Electronics and Software Technology of Guizhou Province,Guiyang 550025,China;Semiconductor Power Device Reliability Engineering Research Center of Ministry of Education,Guiyang 550025,China)

机构地区：[1]贵州大学大数据与信息工程学院,贵阳550025 [2]贵州省微纳电子与软件技术重点实验室,贵阳550025 [3]半导体功率器件可靠性教育部工程研究中心,贵阳550025

出　　处：《半导体技术》2023年第2期151-156,169,共7页Semiconductor Technology

基　　金：贵州大学引进人才项目(贵大人基合字(2019)63)。

摘　　要：设计了一款低失调轨到轨运算放大器。通过利用两个晶体管的基极-发射极(BE)结压降和一个可修调电阻来钳制共射-共基组态中共基对管的集电极电位,同时用电阻代替输入级有源负载,有效抑制了电路失调;偏置电路使用温度系数相反的p型结型场效应晶体管(p-JFET)与Cr-Si电阻结合,产生高精度、低温漂的电流;增益级与输入级组合为共射-共基结构,实现高增益;输出级采用AB类结构,保证轨到轨输出的同时提供足够的驱动能力。基于互补双极型工艺流片,测试结果表明:在电源电压±15 V,共模输入电压为0 V时,输出电压摆幅为-14.97~14.86 V,输入失调电流低于0.8 nA,大信号增益达到121 dB,压摆率为4.28 V/μs。该芯片可应用于便携式电信设备、电源控制与保护、采用轨到轨输入的传感器等领域。A rail-to-rail operational amplifier with low offset was designed.The collector potential of two common base transistors in the common emitter-common basis structure was clamped by using the voltage drop of the base-emitter(BE)junction of two transistors and a tunable resistor.Meanwhile,the input stage active load was replaced with resistance.Finally,the circuit offset can be effectively inhibited.The p-type junction field effect transistor(p-JFET)and Cr-Si resistors with opposite temperature coefficients were used in the bias circuit to generate high-precision low-temperature drift current.The combination of gain stage and input stage adopted the common emitter-common basis structure to achieve high gain.The output stage adopted the AB class structure to ensure rail-to-rail output while providing sufficient driving capacity.The chip was fabricated based on the complementary bipolar process.The test results show that when the supply voltage is±15 V and the common-mode input voltage is 0 V,the output voltage swing ranges from-14.97 V to 14.86 V,the input offset current is less than 0.8 nA,the large signal gain reaches 121 dB,and the voltage swing rate is 4.28 V/μs.The chip can be used in portable telecommunication equipment,power control and protection,sensors with rail-to-rail input and other fields.

关 键 词：低失调 轨到轨 高精度 低温漂 互补双极型工艺 

分 类 号：TN722.77[电子电信—电路与系统] TN431.1