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A Design of Multi-Channel Capacitive Touch Sensing ASIC for SoC Applications in 0.18 ${\mu}m$ CMOS Process  

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)
Publication Information
Journal of the Institute of Electronics Engineers of Korea SD / v.47, no.4, 2010 , pp. 26-33 More about this Journal
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 $mm^2$.
Keywords
Multi-channel; Capacitive touch Sensing; Common processing unit; sensing resolution; SoC;
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Times Cited By KSCI : 1  (Citation Analysis)
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