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

The Institute of Electronics and Information Engineers (대한전자공학회)
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A Design of Multi-Channel Capacitive Touch Sensing ASIC for SoC Applications in 0.18 ${\mu}m$ CMOS Process

0.18 ${\mu}m$ CMOS 공정을 이용한 SoC용 정전 용량형 멀티 채널 터치 센싱 ASIC의 설계

  • Nam, Chul (Department of Electronic Engineering, Konkuk University) ;
  • Pu, Young-Gun (Department of Electronic Engineering, Konkuk University) ;
  • Park, Joon-Sung (Department of Electronic Engineering, Konkuk University) ;
  • Hong, Seong-Hwa (Department of Electronic Engineering, Konkuk University) ;
  • Hur, Jeong (Department of Electronic Engineering, Konkuk University) ;
  • Lee, Kang-Yoon (Department of Electronic Engineering, Konkuk University)
  • 남철 (건국대학교 전자정보통신공학부) ;
  • 부영건 (건국대학교 전자정보통신공학부) ;
  • 박준성 (건국대학교 전자정보통신공학부) ;
  • 홍성화 (건국대학교 전자정보통신공학부) ;
  • 허정 (건국대학교 전자정보통신공학부) ;
  • 이강윤 (건국대학교 전자정보통신공학부)
  • Received : 2009.12.28
  • Accepted : 2010.03.01
  • Published : 2010.04.25
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Abstract

This paper presents a multi-channel capacitive touch sensing unit for SoC applications. This unit includes a simple common processing unit and switch array to detect the touch sensing input by capacitive-time(C-T) conversion method. This touch sensor ASIC is designed based on the Capacitive-Time(C-T) conversion method to have advantages of small current and chip area, and the minimum resolution of the unit is 41 fF per count with the built-in sensing oscillator, LDO regulator and $I^2C$ for no additional external components. This unit is implemented in 0.18 um CMOS process with dual supply voltage of 1.8 V and 3.3 V. The total power consumption of the unit is 60 uA and the area is 0.26 $mm^2$.

본 논문은 SoC 응용에 가능한 멀티 채널 용량형 터치 센서 유닛과 간단한 공통프로세스 유닛, 스위치 어레이를 포함하여 C-T 방법으로 터치 입력을 처리하는 ASIC을 제안하였다. 본 터치 센서 ASIC은 작은 전류와 칩 면적의 장점을 갖는 C-T 변환 방식에 기반 하여 설계하였으며, 최소 센싱 해상도는 한 카운터 당 41 fF이며, 외부 부품 없이 동작하기 위해 내부 발진기 및 LDO 레귤레이터, $I^2C$를 내장하였다. 본 ASIC은 0.18 um CMOS공정으로 구현되어 있으며, 1.8 V와 3.3 V 전원을 사용한다. 전체 소비 전력은 60 uA이고, 면적은 0.26 $mm^2$이다.

Keywords

References

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