可自动调节基准值的电容式触摸检测电路

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关键词：电容式触摸检测电路；可自动调节基准值；数字电路；抗干扰

中图分类号：TN495

文献标识码：A

DOI： 10.14106/j.cnki.1001-2028.2025.1470

引用格式：刘勇，倪屹，赵海，等. 可自动调节基准值的电容式触摸检测电路 [J]. 电子元件与材料， 2025， 44（3）： 285-291.

Reference format： LIU Yong， NI Yi， ZHAO Hai， et al. A capacitive touch detection circuit with auto-adjustable reference value[J]. Electronic Components and Materials， 2025， 44（3）： 285-291.

A capacitive touch detection circuit with auto-adjustable reference

value

LIU Yong 1，NI Yi 1，ZHAO Hai 2，QI Yi 2

（1. School of Integrated Circuits，Jiangnan University，Jiangyin 214401，Jiangsu Province，China；

2. Jiangsu Luojia Juxin Integrated Circuit Design Co.， Ltd.， Wuxi 214122， Jiangsu Province，China）

Abstract： Currently， capacitive touch detection circuits largely rely on the collaboration between hardware and software. Their anti-interference performance is highly dependent on algorithms. This could lead to issues such as high-power consumption and limited applicability. These challenges can be addressed by assigning the tasks of comparison and anti-interference of capacitors to the hardware circuit. In the hardware implementation， an adder was employed to perform real-time comparison between the detected capacitance value and the reference value， which was dynamically refreshed according to changes in the external environment. The circuit can normally operate when the software is in sleep mode. Moreover， the overall circuit area can be further optimized. Simulation and chip test results demonstrate that the designed circuit can effectively resolve the problems of "falsetriggering" and "difficulttriggering". The circuit can detect a minimum capacitance variation of 0.78125%， which is equivalent to the precision of a 7-bit ADC. The static current was 26 μA， and it can operate normally between -40 ℃ and 120 ℃. It can automatically calibrate the reference value according to the external environment.

Keywords：  capacitive touch detection circuit; automatically adjustable benchmark value; digital circuits; anti-interference

长期以来，人机交互方式始终是科学技术发展的重要方向，触摸技术作为一种直观、便捷的输入方式备受关注。（剩余8647字）