Is there anyone on this forum that can help try to trouble shoot a pcb issue on an LCD driver pcb?
I have tried to modify an LCD screen to run on 5v instead of 12V. I have done what was mentioned on this thread above.
the last two posts by Bob the builder are mine, I had to choose a silly name because their server doesnt seem to want to let me in on my normal account.
So the situation is that a power regulator (xl1509-5) was removed, and then 5v was applied directly to the pin that was its output. (pin 2 I think)
This works, and the LCD works, however there are some components that get very very hot. I didnt test the screen more than just a two min test before modding it, so I cant say if this is a result of the mod or not, and the power regulator which was removed was damaged.
All of the components marked in the attacehd file are getting hot, the toroids and diode that are amrked are getting the hottest, I have put a ceramic cap in parallel with one of the originals to see if that helped, and it was reduced the heat on the original cap when compared to the other one, the ceramic also gets warm.
I also put a DMM set to HZ onto the caps, and the readings fluctuated quite a lot.
The MCU on the board gets warm, and I added the heatsink for now. There is a 3.3v power reg feeding the MCU, and I have put the DMM on the cap thats on the 3.3v reg output and there is no ripple i can see.
The reason for wanting to fix this issue is that the screen gets some interference lines on it after about 30 mins,
I will run it again for a long time and take another thermal image when its all piping hot.