Realizing method of capacitance type inductive key, inductive key circuit and keyboard

Abstract

The invention discloses a realizing method of a capacitance type inductive key. A CPU (Central Processing Unit) controls a high-frequency signal generator to feed a high-frequency signal to an inductive signal detection circuit; an ADC (Analog to Digital Converter) is used for acquiring and storing a direct current voltage value output by a detection circuit when no figure touch and press exists as reference voltage; when figure touch and press exists, an inductive capacitor used as a high-frequency signal bypass is formed between an inductive electrode of the detection circuit and the ground so as to reduce the direct current voltage value output by the detection circuit; the ADC detects the changed voltage value, and the CPU compares the changed voltage value with the stored reference voltage to confirm that the finger touch and press action exists. By using the measures of improving the signal frequency and the response speed of the circuit and the like, the invention greatly improves the input speed of the inductive keys and the keyboard, can not only be used for traditional single-key position judgment, but also can be used for sliding (or moving) change judgment and analyzing and processing a plurality of inductive key signals input by sliding keys, dual-key rolls and multi-key rolls at high speed.

Description

technical field [0001] The invention relates to a design technology of a sensor key and a keyboard for electronic products, in particular to a method for realizing a capacitive sensor key, a sensor key circuit and a keyboard, so as to meet the needs of electronic products for high-speed sensor keys and keyboards. Background technique [0002] Ordinary capacitive sensor keys and keyboards are necessary input accessories for many electronic products. With the advancement of technology, many electronic products need to be equipped with sensor keys and keyboards with high input speed. However, the current sensor key technology can only be adapted to single-key input one by one, and the speed is low. When quickly touching the sensor key, double key or multi-key rollover (N-key rollover) input, the sensitivity is low and misoperations increase. Moreover, common capacitive sensing buttons are easily affected by the environment. When environmental factors such as temperature and hu...

AI Technical Summary

Problems solved by technology

However, the current sensor key technology can only be adapted to single-key input one by one, and the speed is low. When quickly touching the sensor key, double-key or multi-key rollover (N-key rollover) input, the sensitivity is low and the misoperation increases.

Moreover, ordinary capacitive sensing buttons are easily affected by the environment

When environmental factors such as temperature and humidity change, it will cause instability or even drift of the capacitive sensor keys, resulting in invalid keys or malfunctions

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