TPA3255 Reference Design Class D Amp with PFFB

X: which silicone thermal spacer pads did you use? Any of the type I normally use between transistors & a heatsink all seem to be too thin. I can still see light passing under the heatsink (that attaches to the 3255 chip) and the chassis floor..

Thanks, Pete
 
Well... today I wanted to start, but sadly the smps is not complete.
It is not fully assembled, but okay, afterwards Sami sent me the assembling instruction, but even so, the mounting clips for the power devices are missing... 🤔 waiting for the answer from Sami :dead:
 
No, I can't. The power devices are soldered into the board and have rubber caps, but the holes for the mounting clips are above the devices, so no chance without clips. I also have to solder the thermal switch, but it's not a problem.
I hope he will send me the clips... Or I have to drill new holes and use Keratherm insulation between the devices and the heatsink... but it's not what I paid for...

PSX_20230302_204717.jpg
 
Hi X,
could you please check and correct (if needed) the following wiring plan for the psu?

  • Main voltage output with the big connectors: to the amp board, it's clear 🙂
  • 12 vdc output to the buffer
  • 3.3 vdc output can be used for an LED on the front with a resistor in series
  • AUX (15 vdc) to the amp board - but in your build (and in the picture above) I see a cap on the top of the connector; is it against turn on bump? If so, which value/voltage is needed?
  • How/where to wire the further contacts (STDBY, DCER, DELAY?)
  • PSU input is J1, whit the left contact live and the right contact neutral? Middle contact not in use?
  • J2 has in your build (and in the above too) a jumper - what is it for?
  • Where can I set the input voltage to 240vac?
  • mains fuse value at 230vac?
  • Is the turn on button a locking one or just a push button without locking?

Really not that much 😀
Many thanks in advance :cheers:
 
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Plott,
Did Sami give an explanation why the SMPS wasn’t 100% assembled?
Vunce,
mainly because of the time; they have long delivery time now as stated on the homepage (at the time of my order it was at least 35 days) and I wanted it a little quicker.
And after the psu was on sale, I accepted the assembly, which was really not a big issue.