Greetings
My first post here. English is not my first language so please mind my grammar.
I'm having trouble with MD8k psu section. It was working perfect before until my car sat in the driveway for 2 days and after that its psu went crazy.
Basically above 12.5V square wave kinda dissapears/becomes very dirty, if i turn down voltage its fine again. Also when its turning on right after square wave is built it dissapears for moment and then comes back. A few times has happened that it doesnt want to turn on at all, or goes into protection with flashing 3x red light(voltage over 16V) while actually getting 12v.
I already swapped out driver ic because i had one laying around and no change.
Cant find anything wrong so im starting to think the 20 pin STM8 programmable chip is faulty because the square wave starts from there.
Maybe someone has had similar problem with brazilians amps.
I did a quick video of it.
August 22, 2020 - YouTube
My first post here. English is not my first language so please mind my grammar.
I'm having trouble with MD8k psu section. It was working perfect before until my car sat in the driveway for 2 days and after that its psu went crazy.
Basically above 12.5V square wave kinda dissapears/becomes very dirty, if i turn down voltage its fine again. Also when its turning on right after square wave is built it dissapears for moment and then comes back. A few times has happened that it doesnt want to turn on at all, or goes into protection with flashing 3x red light(voltage over 16V) while actually getting 12v.
I already swapped out driver ic because i had one laying around and no change.
Cant find anything wrong so im starting to think the 20 pin STM8 programmable chip is faulty because the square wave starts from there.
Maybe someone has had similar problem with brazilians amps.
I did a quick video of it.
August 22, 2020 - YouTube
What your seeing in the video is a regulated power supply doing it’s job. As you increase the voltage it throttles back on the duty cycle. If the amp was under a load the the regulation wouldn’t look so “dirty” on the scope. So I don’t see a problem with the power supply section of the amp.
Hmm sounds about right. I just never would have thought the square wave completely disappears. Have to do some testing with a small load then at the weekend and see what happens. Still wierd that it went into protection for 16V+ but it was nowhere near that. Thanks for the reply.