科学技术与应用

高精度电压基准和偏置电路自动化测试系统

常 淏

南方科技大学 电子与电气工程系

DOI: https://doi.org/10.59429/kxjsyy.v3i4.15205

Keywords: 电压基准；偏置电路；ADS1256；INA240A3；多路复用；树莓派；自动化测试；抗干扰设计

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Abstract

针对实验室 Reference voltage & current 板 mini-PCIE 接口多路电压与电流的高精度测试需求，设计了 一套基于树莓派的自动化测试系统。系统以 ADS1256 24 位 ADC 与 ADR4550 精密基准构建核心采集链路，以 INA240A3 电流检测放大器配合 0.1Ω 开尔文四端采样电阻实现微安级电流检测，通过 4 片 CD4051 同步多路复 用阵列实现 10 路电压与 10 路电流的自动轮询。硬件贯彻模拟 / 数字分区、星型单点接地等抗干扰策略，采用 TPS7A4700+ADR4550 两级稳压。

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