Class D parts help

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Ok Have this generic style class on the bench today.. came in with one blown output and a fried supply.. The supply is no big. Going to use 3205's and switch the gate resistors to 10 ohms. Here's my problem I just want to replace the one bad output without replacing them all.. the part I'm looking for is a RFP40N10.. Mouser shows them as obsolete. Future doesnt show the TO-220 stlye and Ebay wats over $8 a piece!
It being a class D i know it can be one finicky sob.. Should/ can I just replace them all with something else? Or does anyone here have one they want to part with for some $..??
 
The IRF3710Z (note the Z suffix) is often a good sub in the HIP4080 based amps. The IRF3710ZPBF is essentially the same part but lead free.

I'd recommend that you replace all of them. If the power supply didn't fail, it could well fail if the outputs fail again. The remaining outputs were likely pushed right to the point of failure also but the one that failed caused the amp to shut down or blow the fuse.

There's no point in trying to save a few bucks and risk having the amp fail.
 
OK thanks perry.. This poor thing doesnt even have a name on it anymore.. And the board says nothing but d2000.. Did some searching but came up with nothing useful.. I always replace ALL the power supplys.. its cheap insurance on my end.. Would a picture help on determining if those outputs will work?
 
IRF3710Z is a very good replacement but gate charge is substantially lower (resulting in much faster turn on) so the value of gate resistors may have to be doubled (but only for turn on, not for turn off, so look for turn off diodes...) Faster turn off is not usually a problem.
 
The 20 pin IC looks like a HIP4080(A).

The Monacor Carpower D-REX 1200 (probably only sold in Europe and now discontinued) looks like a renewed version of that amplifier design, with some size reduction (a single bigger supply toroid) and migration to SMD. I find a lot of similarities in parts and overall layout, including the "black-box" potted daughter PCB.
 
Except for the color of the board, this appears to be essentially identical to the old Planet Audio PA2500D.

All 3 of the inductors in the upper left of the photo tend to short. When you get the amp working and have all of the power transistors tightly clamped to the heatsink, you'll need twist them gently to see if there are any problems.

If you see sparks between the windings or if the amp begins to draw more/less current when twisting them, they have intermittently shorted windings. You should do this with a 2 ohm current limiting resistor in series with the B+ line. If the inductor just in front of the black box has shorted windings, it could cause enough current to damage the power supply. If you don't have a current limiting resistor, insert a 10 amp fuse in the B+ line.

If none are shorted yet, you need to apply a few drops of an good adhesive like Goop to the terminal windings. Apply it at the top and let it drip down the side of the inductor between the terminal winding and the rest of the windings. This will help prevent them from shorting in the future.

If any of the audio FETs shorted when they failed, you'll need to replace the 4080. They virtually always fail when the FETs short.
 
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