With the FETs in or out of the circuit?
That IC is fairly well isolated from the FETs in most amps. Check the driver transistors and the diodes in that area.
That IC is fairly well isolated from the FETs in most amps. Check the driver transistors and the diodes in that area.
If it uses N and P outputs, the drains should be directly connected. Check for broken inductors, open traces, bad solder connections and pulled vias.
I installed the output fets and the when I power up the amp , it draws 20 amps of current . Plus I was rereading this thread, the 640s gate pins had +6 volts not -6 volts . This has to be why the amp goes red line full amps . Bad drivers but they look good ? Oh and Perry like you said about lnductors the power supply transformer was making a high pitch noise but stopped. I tryed powering the amp and twisting on all inductors but no good , fuse would short out still . Power supply fets heat up and only 640s not 9640s .
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Perry found the problem , it was one 9640 output fet that was getting hot check the gate resistor 8,500 ohms lol open. Put in 22 ohm resistor good to go , thanks Perry . Just one thing I get a small high pitch noise from two of the inductors on the output side , is that normal ?
I've never worked on one of these so I don't know if it's normal. If it's not getting into the audio and the amp works properly otherwise, I wouldn't worry about it.
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