微弱信号的高精度数据采集系统

针对加速度计输出信号微弱的特点，提出了一种基于TMS320F28335、CPLD以及AD7760的高精度数据采集系统设计．加速度计的输出信号经过信号调理电路后进入24位精度AD7760完成模数转换，DSPTMS320F28335作为主控制器，辅以CPLD完成对AD7760转换数据的读取操作，并将数据通过串口发送到上位机．详细介绍了系统的硬件电路设计，包括信号调理电路以及ADC、CPLD、DSP之间的接口电路设计，并介绍了系统的软件设计．实验结果表明，设计的数据采集系统能够完成微弱信号的数据采集任务．

High Precision Data Acquisition System for Weak Signal

According to the weak characteristic of the output signal of accelerometer, we design a high precision data acquisition system based on TMS320F28335, CPLD and AD7760. The output signal of accelerometer after signal conditioning circuit go into 24 bit precision AD7760 to complete analog to digital conversion, DSP TMS320F28335 as the main controller control CPLD to read and write AD7760, DSP also send the collected data to the PC via the serial port. This paper introduces the design of system hardware in detail, including the signal conditioning circuit and the interface circuit between ADC, CPLD and DSE This paper also introduces the software design of the system. The results of experiment show that, the data acquisition system designed can compete the task of acquiring weak signal.