When I apply power to the amp with one fet per bank of the output section, the low side stays cool but the high side gets hot. Any ideas what's causing this? Both waves appear to be identical. Thee 12v pins on the driver ic KA3525 both 12v pins are only reading around 9v. If I go off the center tap they both read 4.3v. Also when I have the rectifiers out the square wave on the power supply fets look like the first image below and when I put them in it looks like the second image below. Any help would be greatly appreciated.
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The waveforms on the power supply change because this is a regulated power supply and the duty cycle is reduced after the target rail voltage is used.
When reading voltages onthe primary side of the power supply, use the main ground terminal as the reference (black probe).
What's the voltage across your B+ and ground terminal when you read 12v on pins 13 and 15 of the 3525?
When reading voltages onthe primary side of the power supply, use the main ground terminal as the reference (black probe).
What's the voltage across your B+ and ground terminal when you read 12v on pins 13 and 15 of the 3525?
I think I get what you're saying. Use the ground pin on the IC for the ground, right? Just to see what would happen I put all the fets in and everything appears to be working. Nice clean square waves on the output gets. I havent had a chance to stress test it yet thought. I'm going to do what u said and see if the voltages are correct first. Thanks for taking the time to help me. Your guide has helped me tremendously. I actually had to buy it twice. The first download was bad because my internet connection kept cutting out. I'm glad I decided to give it a shot a second time. If u ask me it was worth every penny!
I don't see any defective components. The design is poor. In some similar amps, the power supplies would fail when the voltage got low (especially if the amp had remote applied when starting the vehicle). I don't know if that is a problem with these amps. There are things you can do to increase the supply voltage to the drivers and IC but it requires quite a bit of work and I don't know if it's necessary in this amp.
The outputs run hot in these amps. If the current draw isn't more than about 3 amps at idle, it's likely OK.
Did you replace the outputs or are these the originals?
The outputs run hot in these amps. If the current draw isn't more than about 3 amps at idle, it's likely OK.
Did you replace the outputs or are these the originals?
Hi Perry, if you want and time, could you explain (in private) how do you intend to increase the voltage on the IC (SG3525?) And the drivers?
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