This amplifier came in. I wanted to post it up on the formum since I have never had one. The power supply uses irfp1405's. The output section is running IRFP4868. Complaint is that it blew some power supply mosfets and they changed them. And they heated up. So maybe the drivers? But the drive wave form looks ok and all are the same 22khzt. All the resistance across gate to drain match all. Gate resistors are all in tolerence. Which made me want to post it up to see if anyone has has experience with this amplifier. It using the SG3525AP
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It draws current if I try to add a single power mosfet to the board. So I used a capacitor, and this happens to the drive.
Open PNP driver transistors?
Does the signal remain good at the output of the driver IC and at the base of the driver transistors?
Does the signal remain good at the output of the driver IC and at the base of the driver transistors?
Pulled them and tested the drivers are not open i replaced them anyway and the result is the same. drive deforms when a cap is placed in curcuit, or a mosfet? i rechecked all the gate resistors, all good. It remains good at the i/c as well.
Older orion amps had a 10 ohm resistor between the PNP driver collector and ground. Do you read 0-10 ohms between their collector and ground?
would having the rectifiers removed have anything to do with this in this amp perry? I can put them back in curcuit, i removed them to isolate the the problem. Ill remove the output transistors, as I am going to replace the output transistors anyway. i been checking surrounding resistors in the area i cant find any of of tolerence.
The rectifiers won't make a difference.
If this drive circuit uses an emitter-follower pair for the PS FET drivers, the collector of the PNP driver must have a path to ground.
If this drive circuit uses an emitter-follower pair for the PS FET drivers, the collector of the PNP driver must have a path to ground.
How many ohms...
3525 ground leg to primary (main) ground terminal?
C505 negative terminal to primary ground terminal?
3525 ground leg to primary (main) ground terminal?
C505 negative terminal to primary ground terminal?
Are you sure that the square wave on the output legs of the 3525 had a square wave that went to ground?
Doesn't the collector of Q587 connect directly to the negative terminal of C505?
Are you sure that you don't have a problem with your meter or leads?
Doesn't the collector of Q587 connect directly to the negative terminal of C505?
Are you sure that you don't have a problem with your meter or leads?
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