Integrating circuit and capacitance sensing circuit

Abstract

The invention is applicable to the technical field of touch and provides an integrating circuit comprising an amplifier, an integrating capacitor, a discharge capacitor, a first switch and a second switch. The amplifier comprises a first input end; a second input end and an output end which is used for outputting an output signal; the integrating capacitor is coupled between the first input end and the output end; the discharge capacitor comprises a first end and a second end, and the first end is used for receiving a first voltage; the first switch is coupled between the first input end of the amplifier and the second end of the discharge capacitor; the second switch is coupled between the first end and the second end of the discharge capacitor. The integrating circuit can effectively sense changes of capacitance.

Description

technical field [0001] The present invention is applicable to the field of touch control technology, and particularly relates to an integrating circuit and a capacitance sensing circuit capable of effectively sensing changes in capacitance. Background technique [0002] With the increasing progress of science and technology, the operation interface of various electronic products has gradually become humanized in recent years. For example, through the touch panel, the user can directly operate and input information / text / graphics on the screen with a finger or a stylus, saving the trouble of using an input device such as a keyboard or keys. In fact, the touch panel is usually composed of a sensing panel and a display disposed behind the sensing panel. The electronic device determines the meaning of the touch according to the position touched by the user on the sensing panel and the screen displayed on the display at that time, and executes the corresponding operation result. ...

AI Technical Summary

Problems solved by technology

In order to correctly analyze the capacitance change of the capacitor to be measured, the prior art uses an analog-to-digital converter with a large dynamic range (Dynamic Range) and high resolution to analyze the analog output signal, resulting in increased circuit complexity and production costs; another On the one hand, the large dynamic range and high resolution of the analog-to-digital converter are mostly spent on analyzing the fixed signal part of the analog output signal, while the changing signal that has a key impact on capacitance sensing cannot be effectively analyzed

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