Capacitive button

Patent metadata

Field	Value
Publication number	US-2024195415-A1
Application number	US-202118286772-A
Country	US
Kind code	A1
Filing date	May 6, 2021
Priority date	May 6, 2021
Publication date	Jun 13, 2024
Grant date	—

Abstract

A capacitive button capable of improving tolerance to electrostatic discharge is provided. The capacitive button includes: a pair of sensor electrodes which are provided side by side; a floating electrode which is arranged on a front side of the pair of sensor electrodes via an insulating layer; and a ground electrode which is arranged so as to surround the floating electrode, and is grounded without being electrically connected with the pair of sensor electrodes and the floating electrode. By providing the configuration, the tolerance to the electrostatic discharge of the capacitive button can be improved.

First claim

1 . A capacitive button comprising:
a pair of sensor electrodes which are provided side by side: a floating electrode which is arranged on a front side of the pair of sensor electrodes via an insulating layer; and a ground electrode which is arranged so as to surround the floating electrode and is grounded without being electrically connected with the pair of sensor electrodes and the floating electrode, wherein capacitances of the pair of sensor electrodes are detected by a mutual capacitance system each as an excitation electrode and a detection electrode.

2 . The capacitive button according to claim 1 , wherein the pair of sensor electrodes are each divided and capacitance between the pair of sensor electrodes and the floating electrode is the same.

3 . (canceled)

4 . The capacitive button according to claim 1 , wherein the floating electrode has an area corresponding to an area of the pair of sensor electrodes.

5 . The capacitive button according to claim 1 , comprising:
a holding body which holds the pair of sensor electrodes and the floating electrode from a back side; and a tactile switch which is provided on the back side of the holding body, and is pressed when the holding body is moved from the front side to the back side.

6 . The capacitive button according to claim 1 , comprising:
an antenna electrode which is provided side by side with the pair of sensor electrodes in a state of forming a gap with the floating electrode more on a back side than the floating electrode, and is grounded.

7 . The capacitive button according to claim 1 , wherein the pair of sensor electrodes are connected to a circuit to which a microcomputer, a regulator and a regulated power supply are connected, via a resistor and a suppressor, and are set such that a characteristic impedance is electrically uniform with the microcomputer, the regulator and the regulated power supply.

8 . The capacitive button according to claim 1 , wherein the pair of sensor electrodes are connected to a circuit to which a microcomputer, a regulator and a regulated power supply are connected in a state where a power terminal of the microcomputer is connected via a bypass capacitor in the circuit, and are set such that a characteristic impedance is electrically uniform with the microcomputer, the regulator and the regulated power supply.

9 - 13 . (canceled)

Assignees

• Mitsubishi Electric Corp

Inventors

• Inoue Takuya
• Yamazaki Takeshi
• Orita Tae
• Ono Takeshi

Classifications

• H03K2217/96077

  comprising an electrode which is floating · CPC title

• H03K2217/0081

  Power supply means, e.g. to the switch driver · CPC title

• H03K2017/9604

  characterised by the number of electrodes · CPC title

• H03K17/962 Primary

  Capacitive touch switches · CPC title

• H03K2017/9455

  constructional details · CPC title