Circuit Design for Alternating Current Field Measurement Make Use of Lock-in Amplifier

Abstract:

In ACFM, the measured signal is very weak and always inevitably includes the noises and the unwanted signal. Make use of lock-in amplifier technology to have designed a disturbance magnetic field testing circuit which includes eliminating 2.5 volt DC circuit, amplifying and filtering circuit, phase-shifting circuit and switching voltage multiplier. This circuits designed can performe the measurement and do-nosing for weak magnetic signal of ACFM. The experiment indicated that make use of lock-in amplifier technology to design and optimize ACFM detection circuit is an effective method

• Periodical: Applied Mechanics and Materials (Volumes 52-54)
• Pages: 1107-1112
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.52-54.1107
• Online since: March 2011
• Authors: Shang Kun Ren, Yao Yang, Zhong Ji Li
• Keywords: Alternating Current Field Measurement, Lock-In Amplifier Technique, Testing Circuit, Weak Signal Detection

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