FEDEVEL
Platform forum

Fallingelectron , 05-29-2025, 03:00 PM

Hey Robert, I’m one of your students from youtube really enjoy what you do Thankyou very much. I have a question, so I am in the final year of EE and working on final year project its a class D audio amlifier, the problem that i am facing is that the PWM signal has to change reference from power supply ground to negative supply rail. I don’t know what should be the plane under this level shifter transistor should it be the ground or should it be the -supply rail? The photo of circuit is attached

QDrives , 05-31-2025, 03:49 PM

Some serious problems with your circuit, both drawing style and functional.
But on your question about the 'plane' -- you need to see the bigger picture. That bigger picture is missing.

Fallingelectron , 05-31-2025, 10:10 PM

What do you mean by drawing style?

QDrives , 05-31-2025, 10:21 PM

Fallingelectron , 05-31-2025, 10:25 PM

What about the functional issues?

Robert Feranec , 06-02-2025, 05:38 AM

analog is not my area, can't really help much 😦

QDrives , 06-02-2025, 01:28 PM

- Capacitor between Gnd and Gnd... ?
- No base resistor
- Snubber between PWM in (kind of) and PWM out