Electret Microphone Circuit

The circuit starts with the electret microphone.

Electret microphone circuit.

This article describes an compact electret microphone amplifier but you can connect dynamic microphones with low resistance. 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. The putput impedance is determined by r1 and r2. If you leave out r2 the output impedance is roughly the resistance of r2.

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. 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. The diaphragm is made of thin teflon material and is also termed as electret and hence the name electret mic.

Electret microphone amplifier circuit. The electret microphone test circuit schematic is shown below. This electret microphone in particular needs 2 2v of power in order to operate. This electret has a fixed charge c and is embedded between the two electrodes.

As stated the microphone needs power in order to operate. Since the microphone port of a computer provides about 2 3v of power this will perfectly power the electret microphone.