Low noise Mini Electret Microphone PreAmplifier

  • Rajkumar Sharma
  • 37777
    Views
  • easy
  • Tested

img_5973

The single supply microphone pre-amplifier amplifies the output signal of an electret capsule microphone to audio line levels. An op amp is used as a trans-impedance amplifier to convert the output current from the microphone in to a signal level voltage. The circuit works with 9V so it is good choice for battery operated systems.

Features

  • Supply 9V DC
  • Current Approx. 3mA
  • On Board Microphone
  • Very thin and narrow PCB

Schematic

Parts List

bom

Photos

img_5974

Video

OPA172 Datasheet

opa172

PCB

Subscribe
Notify of
guest
12 Comments
Inline Feedbacks
View all comments
JensJ

Thank you for this. Modified it to run on a 5V supply and using another OP-Amp and it works perfectly with those alterations.

Dan Gonzalez

the capacitor C5 is well polarized in the diagram, or is it a misprint

kenahilton

I want to purchase the above microphone preamp. What is the cost in USD and how do I get it?

Javier

Hi! Is it possible to hear some real sound tests? is it possible to get a copy of this mounted for experimental purposes? thanks and good job!! 🙂

Phil Stewart

Hi,
I’m interested in several of these — more if they perform well.
How is performance in the presence of RF interference & nearby electrical devices? The PC board is pretty basic — does it require shielding?
I am interested in either the PC board or assembled device, depending on price. Thanks!

Simon Rung

Hi!
How much for an assembled device?
For now I’m in a prototyping face and i would like to try one of these out.

RELATED PROJECTS

X
ADP3450 Oscilloscope Giveaway

By continuing to use the site, you agree to the use of cookies. more info

The cookie settings on this website are set to "allow cookies" to give you the best browsing experience possible. If you continue to use this website without changing your cookie settings or you click "Accept" below then you are consenting to this.

Close