DIY Class D Audio Amplifier
Why Electrical Engineering Stack Exchange recommends it
Electronics Stack Exchange answerers point people to it as a practical homebuilt amplifier example when someone needs to drive speakers or wants to understand how Class D works.
Recommended by 2 people across 2 different months, 2019 to 2022.
What it is
GreatScott! builds a Class D audio amplifier from discrete parts, using a comparator, a 555-based triangle wave, an IR2113 MOSFET driver and IRLZ44N output transistors. The video is a hands-on build with a custom PCB designed in EasyEDA, plus testing and a final output stage addition.
What people said
Recommends hatsunearu · 2019-03 · Electrical Engineering Stack Exchange · on “Can I connect TV internal Speakers to 3.5mm plug?”
If you're trying to connect raw speakers to a computer, you can't do that. The speakers require a lot more power than what can come out of a computer. The computer can put out enough power for a pair of headphones, which you can only hear if you place your ears right next to it. If you tried what you wrote in the OP, you won't get much volume out of the speakers, and you also risk breaking your computer audio output. You should get yourself an audio amplifier. You can get one at a store, or you can make your own. There are plenty of tutorials online to make the latter. Here's one I particularly like: [this video]
Recommends Unknown123 · 2019-04 · Electrical Engineering Stack Exchange · on “Trying to recover audio from PWM”
Build an LC Low Pass Filter with cutoff frequency around 40kHz. This is the basics of Class D amplifier [this video] .
Cites user136077 · 2020-05 · Electrical Engineering Stack Exchange · on “Trying to understand this Class D amp (using IR2113) circuit”
If you dig up the original Great Scott video you'll see that he has put a 1000uF capacitor in series with the speaker. It can be seen at 5:37 in this video: [this video] It stops the DC component of the output signal. Without it the speaker would get continuous DC about half of the DC supply voltage. It could still work somehow but the dissipation in the speaker would be unacceptable at least for me. I have said it previously in other cases: Do not believe YouTube entertainers. Believe even less those who build their show on some YouTube video. You must get to know the things by understanding them. Your question here shows you have already thought it.
Cites kamal MKA · 2022-10 · Electrical Engineering Stack Exchange · on “My class D amp not working?”
Sorry , GreatScott added the lm386 at the end of the video but I don't why he didn't add it in his schematic , he adds it because he said the the level of the audio signal was too low and the volume of the speaker was low too. This is the video if you want to see : [this video]