Electret Microphone Circuit

An electret is a stable dielectric material with a permanently embedded static electric dipole moment which due to the high resistance and chemical stability of the material will not decay for hundreds of years.

Electret microphone circuit.

The electret microphone test circuit schematic is shown below. Electret microphones can be inserted in the same box with the amplifier it only need 5 to 10v or 9v battery with a current consumption of just 1 5ma. The circuit starts with the electret microphone. As stated the microphone needs power in order to operate.

The diaphragm is made of thin teflon material and is also termed as electret and hence the name electret mic. This electret has a fixed charge c and is embedded between the two electrodes. This is the basic electret microphone powering circuit which you can use as generic reference when receivign circuits which use electret microphones. Since the microphone port of a computer provides about 2 3v of power this will perfectly power the electret microphone.

An electret microphone is a type of electrostatic capacitor based microphone which eliminates the need for a polarizing power supply by using a permanently charged material. An electret microphone mainly consists of a diaphragm a couple of electrodes and an in built jfet. How electret microphones work. 2 the test circuit for an electret microphone the electret microphone jfet amplifier has the gate connected to a pick up plate which is pushed back and forth by the air the source is connected to the ground and the drain is connected to the output pin.

This article describes an compact electret microphone amplifier but you can connect dynamic microphones with low resistance. This electret microphone in particular needs 2 2v of power in order to operate.