Looking for advice on this A1800. I had all the power supply FET's blown, most of the gate resistor out of tolerance. It didn't seem to blow the drivers, they test ok (in circuit). I was going to test it without the FET;s in first. So when I applied power 12.9 volts, both my power and protection light are on.
I have no waveform coming out of the 3525, pin 2 has 6.95vdc on it. Pin 16 (5.1v reg) has 7 volts on it.
Maybe the 3525 is bad, since it blew all the FET's, but it didn't blow the drivers, so maybe not.
I have no waveform coming out of the 3525, pin 2 has 6.95vdc on it. Pin 16 (5.1v reg) has 7 volts on it.
Maybe the 3525 is bad, since it blew all the FET's, but it didn't blow the drivers, so maybe not.
Attachments
Without the pin 1 voltage, the pin 2 voltage is irrelevant.
Did you have the black probe on the 3525 ground pin?
If so, the IC needs to be replaced but it may not be damaged badly enough to prevent it from working. I'd have to see the voltage on all terminals to tell any more about the IC. Copy and paste if you're going to post the voltages.
Pin 1:
Pin 2:
Pin 3:
Pin 4:
Pin 5:
Pin 6:
Pin 7:
Pin 8:
Pin 9:
Pin 10:
Pin 11:
Pin 12:
Pin 13:
Pin 14:
Pin 15:
Pin 16:
Did you have the black probe on the 3525 ground pin?
If so, the IC needs to be replaced but it may not be damaged badly enough to prevent it from working. I'd have to see the voltage on all terminals to tell any more about the IC. Copy and paste if you're going to post the voltages.
Pin 1:
Pin 2:
Pin 3:
Pin 4:
Pin 5:
Pin 6:
Pin 7:
Pin 8:
Pin 9:
Pin 10:
Pin 11:
Pin 12:
Pin 13:
Pin 14:
Pin 15:
Pin 16:
Perry I didn't have it on the 3525 grd pin but the amp ground.
These voltages however are going to be ref to 3525 ground.
Pin 1: 0
Pin 2: 7
Pin 3: 1.15
Pin 4: 1.64
Pin 5: 3.59
Pin 6: 5.74
Pin 7: 3.52
Pin 8: 6.69
Pin 9: 7.63
Pin 10: .799
Pin 11: .759
Pin 12: 0
Pin 13: 11.4
Pin 14: .193
Pin 15: 11.4
Pin 16: 7.03
These voltages however are going to be ref to 3525 ground.
Pin 1: 0
Pin 2: 7
Pin 3: 1.15
Pin 4: 1.64
Pin 5: 3.59
Pin 6: 5.74
Pin 7: 3.52
Pin 8: 6.69
Pin 9: 7.63
Pin 10: .799
Pin 11: .759
Pin 12: 0
Pin 13: 11.4
Pin 14: .193
Pin 15: 11.4
Pin 16: 7.03
Most of the pins have voltage that's too high. If nothing externally is driving pin 16 high, I think the IC needs to be replaced.