The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 12, 2025
Filed:
Mar. 22, 2023
Kazuki Itoyama, Tokyo, JP;
Hajime Kano, Tokyo, JP;
Yuki Uchida, Tokyo, JP;
Takuma Yoshida, Tokyo, JP;
Mitsuaki Daio, Tokyo, JP;
Yasuhiro Horimoto, Tokyo, JP;
Kazuki Itoyama, Tokyo, JP;
Hajime Kano, Tokyo, JP;
Yuki Uchida, Tokyo, JP;
Takuma Yoshida, Tokyo, JP;
Mitsuaki Daio, Tokyo, JP;
Yasuhiro Horimoto, Tokyo, JP;
MMI SEMICONDUCTOR CO., LTD., Tokyo, JP;
Abstract
A MEMS microphone includes a diaphragm having conductivity, first and second variable capacitors respectively including first and second fixed electrodes, a first voltage output section that outputs a first voltage changed according to a change in a capacitance of the first variable capacitor, and a second voltage output section that outputs a second voltage changed according to a change in a capacitance of the second variable capacitor. The first and second fixed electrodes face the diaphragm. The capacitances of the first and second variable capacitors are changed in accordance with a vibration of the diaphragm. A first bias voltage is applied to the first fixed electrode. A reference voltage is applied to the second fixed electrode. A second bias voltage is applied to the diaphragm. A difference between the second bias voltage and the reference voltage is half of a difference between the first bias voltage and the reference voltage.