基于AD7705的高精度极微弱信号A/D转换的电路的设计

在智能仪器仪表设计中,微弱信号转换精度、稳定度的高低直接影响着仪器的性能.为了对极微弱信号进行高精度模数转换,本文设计了以传感器为信号源,仪表放大、低通滤波,运算放大和AD7705芯片为主要结构的转换电路.该电路能够完成对传感器产生的极微弱低频信号进行放大、去噪和模数转换,实验证明本文设计的电路能够有效转换极微弱电信号,为极微弱信号传感器在智能设备中的具体应用提供了合理的解决方案.

The Design of Extremely Weak Signal A/D Conversion Circuit Based on AD7705 High Precision Chip

In the design of intelligent instrumentation,the level of a weak signal conversion accuracy and stability directly affects the performance of the instrument. In order to transform extremely weak signals with high precision,a cricuit with sensor signal source,instrumentation amplifier,a low-pass filter and AD7705 chip as the main structure was designed. The circuit was able to complete producing a extremely weak low-frequency signal which was generated by the sensor amplification,reducing noise and transforming analog to digital. And the experiment could prove that it could effectively convert extremely weak signals,and provide a reasonable solution for a weak signal sensor in the application of intelligent device.