Class D schematic and PCB

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pompeiisneaks
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Re: Class D schematic and PCB

Post by pompeiisneaks »

I haven't updated the schematic yet, but the vcc came from my bench power supply, I connected the - to the B- and the 12VDC+ to the connection at pin12. The mosfets I used were 100V 50A STP40NF10 from mouser here: https://www.mouser.com/QuickViewProdDet ... kView=true Everything else is pretty much the same. B+/B- of 48VDC+/- 12VDC at VCC with - at B-.

so even if it starts at -48VDC instead of -35VDC it will still be ~5VDC range? Why was I measuring 9VDC then? I'm using the 8.2k 1.2k as the schematic denotes. Could that have been due to the failure of the device itself sending 9v from somewhere else through the burned IC?

~Phil
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Re: Class D schematic and PCB

Post by pompeiisneaks »

Here's the updated schematic, with the new voltages and fets
ClassDRev1.png
~Phil
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Re: Class D schematic and PCB

Post by pompeiisneaks »

I also got some help on both EEVBlog and diyaudio, I'm following up there, but figured I'd share here.

One thing that was noted is there are two reference schematics, in one there's a 150pF cap to ground on the NFB line, mine didn't have that, and it might be to tame oscillations that might have been what killed the chip.

I'm attaching that revision here for information.
TypAppDiag.png
~Phil
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