基于ARM的高精度功耗测量仪器设计

Design of High Precision Power Consumption Instrument Based on SEP3203

本文介绍了一种基于ARM7TDMI处理器的数据采集模块的实现方法。该模块可以对电压、电流、热电阻、热电偶、开关量等多种物理量进行测量。ARM处理器与数据采集模块之间采用模拟SPI协议进行数据传输。为了实现高精度,采用了24位A/D。经过对电路的多次改进,该模块目前已能测准到万分之一的精度,优于现在的工业标准。

A design method based on ARM processor of multichannel high precision data acquisition unit is introduced in this article. Physical quantity such as voltage, current, thermo resistance, thermocouple and switching value can be measured by this unit. Data is transferred through simulative SPI protocol between ARM and data acquisition module. To achieve high precision, A 24 bit A/D is used. Now one out of ten thousand precision can be achieved after several times of improvements of the circuit and the precision is better than present industry standard.