Electret Microphone Circuit Amplifier

This electret microphone in particular needs 2 2v of power in order to operate.

Electret microphone circuit amplifier. The circuit starts with the electret microphone. Since the microphone port of a computer provides about 2 3v of power this will perfectly power the electret microphone. A simple pre amplifier circuit for the electret microphone. One of the most common amplifier is the class a amplifier which basically uses a single transistor in common emitter configuration to produce a large output voltage from a relatively small input voltage.

Electret microphone uses electrostatic capacitor inside a capsule. The electret microphone pre amp scheme is very simple and based on available today components. Now in input section we have used an electret microphone. A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power.

One electrode of the capacitor is formed by a metallization layer on the charged polymer film. This article describes an compact electret microphone amplifier but you can connect dynamic microphones with low resistance. Microphone capacitor with electret jfet figure 2. Electret condenser microphone amplifier circuit.

As stated the microphone needs power in order to operate. 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 microphone pre amplifier circuit. Modern electret microphones use ptfe plastic either in film or solute form to form the electret.

It is composed of semiconductor material with at least three terminals for connection to an external circuit. This is another a circuit diagram of homemade mic speaker amplifier using lm386. As per the datasheet a design the 10uf capacitor is connected across these two pins and due to this the output of the amplifier is fixed to 200x. Electret microphone amplifier circuit.

Following completion of this lab you should be able to describe the basic operation of an electret microphone explain one way to bias op amp based circuits for single supply operation describe amplifier clipping and be able determine the dc and ac gains of a non inverting operational amplifier circuit. Learn more about using lm386 audio amplifier ic here. The op amp provides an amplification of about 30 db which is sufficient for the relatively high output level of an electret microphone this gain depends on the value of resistors r3 and r4. This is small and powerful for a low power supply.