Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Microphone interface circuit

A technology of interface circuit and microphone, which is applied in the direction of transducer circuit, electrical components, sensor components, etc., can solve the problems of power difference, power signal, circuit disturbance, interference ground wire, etc., and achieve the goal of improving power supply rejection ratio and eliminating noise Effect

Active Publication Date: 2010-12-01
AAC ACOUSTIC TECH (SHENZHEN) CO LTD
View PDF3 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, when the bias current enters the circuit through the power supply, it will cause unnecessary disturbance to the circuit, produce a poor power signal to the power supply and interfere with the ground wire; at the same time, the charge pump noise that provides the bias voltage for the MEMS microphone will also pass through The equivalent capacitance of the MEMS microphone enters the input of the impedance converter and directly outputs
In this way, the power supply rejection ratio of the MEMS microphone is reduced, and the adverse effects of high noise

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Microphone interface circuit
  • Microphone interface circuit
  • Microphone interface circuit

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0016] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0017] Such as figure 2 As shown, the microphone interface circuit of the present invention includes a power supply module that provides an operating voltage to the microphone via the first node P, an impedance converter that is provided with a first input terminal A and accepts the output signal of the microphone, and is coupled to the impedance converter and the microphone interface circuit An amplifier between the output terminals, wherein the impedance converter is further provided with a second input terminal C, and an impedance matcher is coupled between the first node P and the second input terminal C of the impedance converter.

[0018] The above microphones are MEMS microphones. The power module includes a charge pump that provides a bias voltage for the MEMS microphone via the first node P, a bandgap reference and a linear voltage regulator ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention provides a microphone interface circuit, comprising a power supply module, a resistance convertor and an amplifier, wherein the power supply module provides working voltage for a microphone via a first node; the impedance transformer is provided with a first input end and a second input end, receives an output signal of the microphone; the amplifier is coupled between the impedance transformer and the output end of the microphone interface circuit; and a impedance matcher is coupled between the first node and the second input end of the resistance convertor. The invention can well improve rejection ratio of the power supply, effectively eliminate noise signals and enhance the tone quality of the microphone.

Description

【Technical field】 [0001] The invention relates to an interface circuit, in particular to an interface circuit of a MEMS microphone. 【Background technique】 [0002] With the rapid increase in demand and applications, microphones have become an indispensable component in most electronic products, such as portable electronic products such as mobile phones and notebook computers. For the main components of communication, high-quality, low-noise microphones have always been strongly demanded by most users. At the same time, the interface circuit that plays a major role in the intrusion of external noise interference signals is also more concerned. [0003] Micro-Electro-Mechanical-System Microphone (MEMS for short) has always been favored for its small size, excellent acoustic characteristics and low cost. The advantages of high output impedance and high sensitivity of MEMS microphones have always been the choice of many users. [0004] Such as figure 1 As shown, it is a micro...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): H04R3/00
Inventor 杨勇刚林海徐音司鹏飞郭增良翟鲁坤
Owner AAC ACOUSTIC TECH (SHENZHEN) CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products