Implementation of Capacitance Measurement Equipment for Fault Diagnosis of Multi-channel Ultrasonic Probe

다중채널 초음파 프로브 고장진단을 위한 커패시턴스 측정 장치 구현

  • Received : 2015.09.29
  • Accepted : 2015.11.06
  • Published : 2016.01.31


In this paper, we propose the method to measure the capacitances using not LCR meter but capacitance to voltage(C/V) conversion. And we design the analog MUX circuits that convert 192 channels to 6 MUX channels in order to implement the diagnosis of multi-channel ultrasonic probe. This paper derives the conversion function that converts the digital voltage of each MUX channel to the capacitance using the least squares method because the circuit characteristics that convert the voltage of each MUX channel to the capacitance are different. The developed prototype illustrates the performance test results that the measure times are measured by within 4sec and the measure error rates of maximum, minimum, and average values are within 5% in terms of the repeated measurements of all 192 channels.


Capacitance Measurement;Fault Diagnosis of Ultrasonic Probe;LCR Meter


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