DIY Class a Amplifier

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About: Eletronic, robotics and physics lover

Hi, today I will share with you my little amplifier, is not very powerful but I love it.

Step 1:

You need:

1x Power bank

1x IRF3205

1x 275k,

1x 0,1k

1x 450k

1x 37Ohm

2x 2200uF

1x 100nF

Speaker

Voltmeter

Breadboard

Jumper wires

Step 2:

In the schematic we can see the 37Ohm resistor that has a power of 2W, the other are 1/8W and are enough critical, you should see a voltage of 2,5V across the big resistor if all works correctly.

This is a class A amplifier and use a power n-mos as a switch, but is not very efficient, so the power mos need a heat sink because is get warm quickly as the big resistor.

A 0,1k resistor in parallel to the speaker will give a less inductor and a more resistive load.

Step 3:

I haven't used a clean audio source file, but I hope you like it, bye.

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    3 Discussions

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    gm280

    10 months ago

    Amplifiers are so easy to make. And discrete components can be used to build one as well. But if you wanted a small package amp that works very well with very few components, try an LM386 IC and see how that works for you. It can be fitted into a really small package with lots of power. Even works great for a headphone amp.

    2 replies
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    Adamnearevagm280

    Reply 8 months ago

    Seems very handy chip, thank you

    0
    None
    Adamneareva

    Reply 8 months ago

    Very good, but I'm still afraid about dc voltage across the speaker that can blow it and the spring effect of the diaphragm of the speaker, more powerful in one side, less in the other, anyway thank you very much I'm glad you like it.