Posts

Showing posts from December, 2017

LTC3780, preparing the new board

Image
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 w