Journal of the Institute of Electronics Engineers of Korea SD (대한전자공학회논문지SD)

The Institute of Electronics and Information Engineers (대한전자공학회)
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A Full Digital Capacitive Sensor for Touch Key Applications

터치키 응용을 위한 풀 디지털 정전용량 센서

  • Seong, Kwang-Su (School of Electronic Eng., Communication Eng., & Computer Science, Yeungnam University) ;
  • Lee, Mu-Jin (Department of Electronic Engineering, Yeungnam University)
  • 성광수 (영남대학교 전자정보공학부) ;
  • 이무진 (영남대학교 전자공학과)
  • Published : 2009.06.25
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Abstract

In this paper, a full-digital capacitive sensor for touch key applications is proposed. The proposed circuit consists of two capacitive loads to measure and a resistor between the capacitive loads. As the method measures the delays of the resistor and two capacitive loads respectively, and obtains difference between the capacitive loads by subtracting the two delays, it can reduce the effects of changing of operating environment variables such as supplying voltage, temperature and humidity. Experimental results show the method has l.02pF resolution and can be applied to touch key applications.

본 논문에서는 터치키에 응용할 수 있는 풀 디지털 방식의 정전용량 센싱 기법을 제안한다. 제안된 회로는 측정하고자 하는 정전용량 두 개와 두 정전용량 사이 저항으로 구성된다. 각 정전용량과 저항으로 지연을 측정한 후 두 지연의 차이로 측정하고자 하는 두 정전용량의 차이를 구하는 방식으로 동작전압, 온도, 습도와 같은 동작환경변화의 영향을 완화시킬 수 있는 장점이 있다. 실험결과 제안된 방식의 정전용량 해상도가 1.02pF이어서 터치키에 적용할 수 있음을 보였다.

Keywords

References

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