LTC3780, preparing the new board

Received the new board after i fried the old one

The changes are very minimalistic now that i know that board :


1- Remove the shunt resistor on the bottom right and short circuit it with a bit of  nickel ribbon.
2- Remove the right hand pot, we'll connect our own. The feedback pin is the left pin of the pot. It will be connected to our current control.

As usual, the board did light the "fault" led upon arrival when powered by 12v
Pin 7 of the LM358 was at 0 v, so it was the input voltage pot (the left one), turn it a bit and we are good.

I dont care about the CC pot, as shortcircuiting the shunt disables the CC mode altogether.
Be very sure to use good connecting gears to the spot where the pot used to be

Remember : open loop on that => fried LTC3780


Everything seems to work except in CC mode
The output looks like that :

Way too much ripple.
After checking, i had to decrease the output resistor of the comparator to cope with the buck module i was using while waiting for the new board.
With that new value (100 Ohm),  the low pass frequency is WAY too high.

I'll fix that next time, after receiving the DAC i've ordered to replace the crappy max current  pot.


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