摘要
针对可编程增益仪表放大器(PGA)采集电阻传感器信号时,增益误差较大、噪声较高等问题,设计一种应用于模拟前端(AFE)测量电阻传感器信号的高性能PGA。采用了电压模放大器和电流反馈放大器双模式架构,实现信号的低增益和高增益的精确放大。数模转换器通过电压叠加和电流叠加的方式进行失调补偿。置位于不同增益倍数时,电路在两种模式下自动切换,以提高电路工作效率。电路设计基于TSMC 0.18μm工艺实现。后仿真结果表明,PGA在1~2048放大倍数的增益误差最大不超过0.04%,失调补偿范围±500 mV,在256倍放大倍数下,100 kHz处噪声的功率谱密度为17.5 nV/Hz^(1/2),在1~100 kHz带宽内输入参考噪声为5.79μV,输入阻抗大于1 MΩ,在电源电压1.8~3.6 V内正常工作。
To address such problems as large gain errors and high noise of programmable gain amplifiers(PGA)during collecting resistive sensor signals,a high-performance PGA was designed for analog front-end(AFE)measurement of the resistive sensor signals.A dual-mode architecture of voltage-to-analog amplifier and current feedback amplifier were used to achieve precise amplification of signals at low and high gains.The digital-to-analog converter compensates for the offset by superposing voltage and current.When set at different magnifications,the circuit can automatically switch between the two modes to improve the efficiency of the circuit.The circuit design is based on the TSMC 0.18μm process.The post-simulation results show that the gain error of PGA at 1-2048 magnification does not exceed 0.04%,and the offset compensation range is±500 mV.At 256 magnification,PGA has a power spectral density of 17.5 nV/Hz^(1/2)at 100 kHz,and equivalent input-referenced noise is 5.79μV within 1-100 kHz bandwidth.The input impedance of PGA is more than 1 MΩ.PGA can work normally within the supply voltage of 1.8-3.6 V.
作者
任建
许少东
辛晓宁
许智超
REN Jian;XU Shaodong;XIN Xiaoning;XU Zhichao(School of Information Science and Engineering,Shenyang University of Technology,Shenyang110870,China)
出处
《电子元件与材料》
CAS
北大核心
2023年第10期1250-1255,共6页
Electronic Components And Materials
基金
国家自然科学基金面上项目(6187011861)
辽宁省教育厅青年育苗项目(LQGD2020009)。
关键词
仪表放大器
高精度
失调补偿
低噪声
双模式
instrumentation amplifier
high precision
offset compensation
low noise
dual-mode
