Double-coupling detection circuit, rain sensor and rain identification method

Abstract

The invention is applied to the technical field of electronic sensors, and provides a double-coupling detection circuit, a touch screen terminal, a rain sensor and an automobile. The double-coupling detection circuit comprises an induction electrode, a cross-coupling electrode, a first driving signal generating unit, a self-coupling electrode, a second driving signal generating unit, and an AD detection channel. The cross-coupling electrode is coupled to the induction electrode; the first driving signal generating unit drives the cross-coupling electrode; the self-coupling electrode is electrically connected with the induction electrode through a resistor or an equivalent resistor and is driven with the cross-coupling electrode at different time intervals; the second driving signal generating unit drives the self-coupling electrode and is connected with the self-coupling electrode; and the AD detection channel is used for receiving a detection signal input by the induction electrode. By combining the self-coupling and cross-coupling detection, the aim of effectively distinguishing the rain from human hands or other grounded conductors can be fulfilled through the simple detection circuit based on the capacitance detection technology with optimized stability and flexibility. Particularly, when the detection circuit is applied to an automotive windshield, the action of a wiper blade can be effectively detected. Therefore, the control of the automotive wiper blade can be more accurate.

Description

technical field [0001] The invention belongs to the technical field of electronic sensors, and in particular relates to a double-coupling detection circuit, a rainfall sensor and a rainfall identification method. Background technique [0002] The existing rainfall detection technologies include: groove etching metal detection, infrared induction detection, photoresistor detection, capacitive induction detection, etc. [0003] The groove etching metal detection requires etching grooves on the glass, and then etching the rain sensor into the groove with double-layer metal. When it rains, the rainwater flows into the groove and short-circuits the metal to achieve detection. This approach is difficult and inflexible. [0004] Infrared detection is to install the detector on the inside of the glass, and the infrared light emitted by the transmitter is refracted by the glass, and then received by the receiver. When it rains, water droplets are attached to the glass surface, and ...

AI Technical Summary

Problems solved by technology

[0007] The purpose of the embodiments of the present invention is to provide a double-coupled detection circuit, aiming to solve the problems of high technical difficulty, poor flexibility, poor stability and susceptibility to interference existing in the existing rainfall detection technology

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