I'm working on a class d amplifier at 300khz pwm at 0-5v and -2 to 2 v sine wave input, I've attached the schematic below for anyone who wants to have a look at it(please use the online simulator from infenion or else the schematic might not open) I understand this post is very vauge of me, but i just want some advice on how to continue and debug this issue
You have 2 issues. Your 100k feedback resistors are going to the wrong place. They are tied to the output of the OPAMP instead of the input of the OPAMP. Also, you are trying to do a differential output so you need a differential input stage. Both outputs change together in a differential fashion so you need a difference sensing circuit. If the 2 feedback resistors go to the same point then how can you know what state either output is in? That would mean that the output voltages are being summed in a feedback loop and the sum is a constant voltage in this case because one output goes up at the same rate that the other one goes down. You need to sense the difference in these 2 outputs in a control loop.
