作者：范明明1, 杨录2, 任超瑛1
作者单位：1. 中北大学信息与通信工程学院, 山西太原 030051;
2. 电子测试技术国家重点实验室, 山西太原 030051
关键词：逐次逼近型ADC; 模拟输入前端; 信号调理电路; 滤波器设计; 放大器选择;
摘要：
为设计出与逐次逼近型(SAR)ADC输入适配且性能优良的信号调理电路,综合考虑分析模拟输入信号、SAR型ADC接口的前端、基准电压源和数字接口,根据噪声分析理论给出前端RC滤波器的详细设计公式和设计过程,并根据滤波器的带宽和系统噪声容限选择前端驱动放大器。通过对比芯片官方参考电路和实际测试效果表明:计算公式有效可行,放大器的分析选择科学合理,为SAR型ADC前端信号调理电路的设计提供可靠依据。
Front-end signal conditioning circuit design for SAR analog-to-digital converter
FAN Ming-ming1, YANG Lu2, REN Chao-ying1
1. College of Information and Communication Engineering, North University of China, Taiyuan 030051, China;
2. State Key Laboratory for Electronic Measurement Technology, Taiyuan 030051, China
Abstract: For the purpose of designing an excellent performance signal conditioning circuit to adapt to the input of successive approximation (SAR) ADC. Considering and analyzing the analog input signal, ADC interface front-end, voltage references and digital interface, and according to the noise analysis theory, the authors gave detailed front-end RC filter designing equations and process. According to the filter bandwidth and system noise tolerance, the front-end driver amplifier was chosen. The result obtained by comparing the official reference circuit of the chip and comparing the actual test shows that the formula is effective and feasible. The analysis of the operational amplifier and selection is scientific and reasonable. All this provides a reliable basis for designing the front-end signal conditioning circuit.
Keywords: SAR ADC; analog input front-end; signal conditioning circuit; filter design; amplifier selection
2014, 40(6): 79-83 收稿日期: 2013-12-11;收到修改稿日期: 2014-1-23
基金项目:
作者简介: 范明明(1990-),男,江西抚州市人,硕士研究生,专业方向为电磁超声无损检测及其信号与信息处理。
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