摘要
针对基于AD5933的阻抗测量仪不能测量100 Ω以下阻抗和不能自动切换档位的问题,提出一种大量程、全自动阻抗测量仪,特点：测量范围10Ω～1 MΩ、精度±5‰,将AD5933的最小测量值由1 kΩ扩展到10 Ω;基于ISL84684的十六路模拟开关矩阵,导通电阻0.25 Ω,导通时间12 ns,截止时间5 ns,为档位自动切换奠定了基础;基于REF3033的基准电压模块,输出电压3.3V、精度±2‰,为A/D转换精度提供了保证;基于VC6.0上位机系统,实现参数设置,数据处理、显示与存储,为分析和应用搭建了平台.实测表明：本阻抗测量仪结合自适应算法,实现档位自动切换,既可避免手动切换的盲目性,又可保证不同档位具有相同的精度±5‰,拓展了AD5933的测量范围,实现了全量程自动测量.
Aiming at the problems that the impedance measuring instrument based on AD5933 can not measure the impedance under 100 Ω and can not switch the measurement ranges automatically,a wide-range and automatic impedance measuring instrument was developed.The instrument has the following features：measurement range from 10 Ω to 1 MΩ; precision of ± 5‰ ; especially,extending the minimum range from 1 kΩ （for AD5933） to 10 Ω ; a 16 channel analog switch matrix based on ISL84684 with on resistance of 0.25 Ω,turn-on time of 12ns,and turn-off time of 5 ns,which provides a good foundation for automatic range switching; and a reference voltage module based on REF3033 with output voltage of 3.3V and precision of ± 2‰,which guarantees the ADC precision; A host computer system based on VC6.0 achieves the parameter setting,data processing,display and storage,which provides a platform for software analysis and application.The measurement results show that the instrument combining adaptive algorithm could achieve automatic range switching,it not only avoids the blindness of manual range switching,but also guarantees the same precision of ± 5‰ in all ranges.The instrument expands the measurement range of AD5933 and achieves automatic measurement in the whole range.
出处
《仪器仪表学报》
EI
CAS
CSCD
北大核心
2014年第4期859-865,共7页
Chinese Journal of Scientific Instrument
基金
山西省科技攻关项目(20130321014-02)
山西省自然科学基金(2011011015-2)
新型传感器与智能控制教育部重点实验室(太原理工大学)开放课题基金(N201309)资助项目
关键词
测量仪
阻抗
自适应算法
AD5933
measuring instrument
impedance
adaptive algorithm
AD5933
