Working on a Hifonics Maxximus X4 2 channel class D, two boards in one housing. When switching on, it goes directly in protect, with very low inrush current.
When I quick "pulse" the remote of the power supply for about one minute , I got about +/-30V rail voltage. Inrush current about 1A. Power on and protect led is flashing.
Mosfets both boards PS and amplifier are OK.
I sustpect the protection itself, but I'm not familiar with the boards used.. some pics of the boards and PS driverboard. If there are schematics available for this amp or similar ones, that would be a great help for me.
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When I quick "pulse" the remote of the power supply for about one minute , I got about +/-30V rail voltage. Inrush current about 1A. Power on and protect led is flashing.
Mosfets both boards PS and amplifier are OK.
I sustpect the protection itself, but I'm not familiar with the boards used.. some pics of the boards and PS driverboard. If there are schematics available for this amp or similar ones, that would be a great help for me.
.No, just the power supply drivercard fore- and backside.
The LM339's (last picture) are near the amp mosfets
The LM339's (last picture) are near the amp mosfets
Are there any components on the bottom of the main board?
Can you power only one board at a time to see if you can get it to power up?
What was the complaint from the owner?
Can you power only one board at a time to see if you can get it to power up?
What was the complaint from the owner?
I didn't remove the boards from the heatsink (yet...).
Power cable's from the powerterminal to the 2nd board I have to desolder first, to power one board...
Complaint was that is was stuck in protection, no other info available atm.
Power cable's from the powerterminal to the 2nd board I have to desolder first, to power one board...
Complaint was that is was stuck in protection, no other info available atm.
Look under the board with a flashlight (torch?) to see if there are any components there.
Can you break the remote connections and power them separately?
Can you break the remote connections and power them separately?
Finally I succeed in repairing this amp. One board had a feedback resistor 33k Ohm open, from output to feedback input of class d driverboard. Resistor was invisible because of the fixation kit of the output coil. Lots of hours of troubleshooting, and one smd resistor 33k 0805....
