基于TMS320VC5509与AD7322的数据采集系统的设计

摘要

In order to enhance the signal sampling rate and conversion accuracy and to reduce system power consumption,a kind of dada acquisition system is designed based on the fixed-point DSP TMS320VC5509 and 2-channel,software-selectable,true bipolar input,1MSPS,12-Bit plus sign,successive approximation type ADC,AD7322,and the principle of hardware circuit and the method of connection and acquisition process are introduced.TCD1206SUP linear CCD with 2160 cells is adopted as image sensor,after CCD completes scanning data,the output of video signals will be filtered by a second-order active low pass circuit,these signals will be collected by the high speed serial ADC,AD7322,which will convert them to digital signals and be sent into DSP.The test result indicates that the system scheme designed is reasonable and design purpose and requirement are reached.%为了提高数据采集系统的采样速度、转换精度、降低系统功耗,设计了一种采用TI公司的C5000系列定点DSP芯片TMS320VC5509和ADI Device公司的2通道的、软件可选的、双极性输入的、最高转换速率是1MSpS、12位的带符号的逐次逼近型串行AD7322的数据采集系统,并阐述了该系统的主要硬件电路的搭建原理、连接方法以及采集过程。该系统的前端数据采集单元采用2160像元的TCD1206SUP线阵CCD作为图像传感器,CCD输出的视频信号经过一个二阶有源低通滤波电路进行滤波后,被高速串行A/D转换器AD7322采集并转换成数字信号,然后将数字信号送进DSP。通过测试表明,该系统设计方案合理,达到了设计目的和要求。