Title:
PIEZOELECTRIC MEMS MICROPHONE
Document Type and Number:
WIPO Patent Application WO/2021/134672
Kind Code:
A1
Abstract:
Provided is a piezoelectric MEMS microphone, comprising a substrate provided with a back cavity, a vibrating diaphragm suspended in the back cavity, and an elastic support piece connected between the vibrating diaphragm and the substrate; the vibrating diaphragm is fixed on the substrate, two sides of the side surface of the vibrating diaphragm away from the back cavity along the vibration direction of the vibrating diaphragm are respectively provided with a first piezoelectric diaphragm, the side surface of the vibrating diaphragm facing the back cavity is provided with a second piezoelectric diaphragm, and the second piezoelectric diaphragm is connected in parallel to the first piezoelectric diaphragm. In the present design, a structure corresponding to the second piezoelectric diaphragm corresponding to the first piezoelectric diaphragm above the vibrating diaphragm is mainly prepared below the vibrating diaphragm, and the second piezoelectric diaphragm is connected is parallel to the first piezoelectric diaphragm. The design slightly reduces sensitivity, but significantly decreases noise since the capacitance is doubled after the parallel connection, such that the total signal-to-noise ratio (SNR) is considerably increased.
Inventors:
TONG BEI (CN)
SHI ZHENGYU (CN)
SHEN YU (CN)
LI YANG (CN)
SHI ZHENGYU (CN)
SHEN YU (CN)
LI YANG (CN)
Application Number:
PCT/CN2019/130909
Publication Date:
July 08, 2021
Filing Date:
December 31, 2019
Export Citation:
Assignee:
AAC ACOUSTIC TECH SHENZHEN CO LTD (CN)
AAC TECH NANJING CO LTD (CN)
AAC TECH NANJING CO LTD (CN)
International Classes:
H04R17/00; H04R1/28; H04R7/16
Foreign References:
| CN110381428A | 2019-10-25 | |||
| CN106911990A | 2017-06-30 | |||
| CN101931850A | 2010-12-29 | |||
| CN102065354A | 2011-05-18 | |||
| US20120308066A1 | 2012-12-06 |
Attorney, Agent or Firm:
GUANGZHOU YUEXIU JILY PATENT & TRADEMARK LAW OFFICE (CN)
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