• Corpus ID: 6851317

A Capacitive Sensor Interface Circuit Based on Phase Differential Method

  title={A Capacitive Sensor Interface Circuit Based on Phase Differential Method},
  author={Hairudin Abdul Majid and Nabihah Razali and M. S. Sulaiman},
  journal={World Academy of Science, Engineering and Technology, International Journal of Electrical, Computer, Energetic, Electronic and Communication Engineering},
  • H. Majid, Nabihah Razali, M. Sulaiman
  • Published 22 July 2009
  • Computer Science, Engineering
  • World Academy of Science, Engineering and Technology, International Journal of Electrical, Computer, Energetic, Electronic and Communication Engineering
A new interface circuit for capacitive sensor is presented. This paper presents the design and simulation of soil moisture capacitive sensor interface circuit based on phase differential technique. The circuit has been designed and fabricated using MIMOS’ 0.35μm CMOS technology. Simulation and test results show linear characteristic from 36 – 52 degree phase difference, representing 0 – 100% in soil moisture level. Test result shows the circuit has sensitivity of 0.79mV/0.1 phase difference… 

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