A High Precision Pico-Amperes Scale Current Measurement System in Radiation Detection

Abstract:

A weak current measurement system is developed. It is mainly used in the accurate measurement of weak current in radiation detection. The principle of the measurement system is introduced. The interference protection measures of current to voltage (I-V) conversion and amplification unit, the technology of ∑-△ ADC and the program design of micro-programmed control unit are described. The system is able to communicate with the computer controlled platform by the USB interface, which has the functions of storage, range selection, data display, data plotting and so on. The measuring range is from 0.1pA to 2.1mA, and the resolution is 5½ bits. The system has been successfully used in the detection of radiation.

• Periodical: Applied Mechanics and Materials (Volumes 239-240)
• Pages: 145-151
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.239-240.145
• Online since: December 2012
• Authors: Jing Wang, Bin Kang Li, Lin Bo Ruan, Geng Tian, Xian Bao Li, Hong Guang Qu
• Keywords: Automatic Measuring Instrument, Current to Voltage Converter, Interference Protection Measure, Weak Current Measurement

References

[1] S. Franco: Design with Operational Amplifiers and Analog Integrated Circuits 3rd Edition The McGraw-Hill Companies, USA (2002).

[2] OKAMURA M: OP amplifier design (Scientific Publications, Beijing 2004).

[3] David J: A Brief Introduction to Sigma Delta Conversion, http: /www. intersil. com.

[4] S. S. Qian: Uncertainty in Measurement: Processing and Expression of Measurement Results, Tsinghua University, Beijing (2002).