Borked the LCD... :/

Well, another of those “i fucked up during building” -threads :confused:
My shruthi-1 worked perfectly well for about half an hour, then the lcd “dropped out”, IE only the backlight was on, and no characters were displayed… I disconnected and reconnected power, and it came back on, but 10mins later it died again, and no amount of powercycling fixed it.
I accidentally touched the edge of the LCD, which instantly brought everything back, but it vanished a couple of seconds later… Having figured out that it must be a cold solder joint somewhere along the LCD connection section, i resoldered every single pad from both sides, but to no avail. -This was one week ago, now the LCD is completely dead, only the backlight is on, and every now and then when plugging in power it will briefly work (1-10mins)… No amount of pressure on the LCD makes a difference… Have i managed to fuck up the digital board LCD section, or should i look elsewhere for problems? Everything BUT the LCD works flawlessly, and i have already heard some amazing sound coming from my speakers :smiley:
Oh yeah, and a quick sidenote on the LCD - in between the backlight and the display part there’s some of that black foam stuff used for the atmega chip that was packaged in along with the LCD… Its not very noticeable, except when the LCD “drops out”… Since theres nothing conductive in there i doubt thats the culprit… :confused:

The black foam IS CONDUCTIVE to protect the Chips during shipping. Try to get it out. Also check the Trimpot (the connection to GND is my personal favourite for bad solder joint and nonworking LCDs…)

Sorry, i meant inside of the lcd at that point (plastic vs plastic/glass) ^^
I’ve got the creeping feeling that it may be the trimpot… Will resolder it when i get home ~40mins…

Ok, if its inside… im clueless wwhat to do ;-). Hope its just the trimpot, have a look at the GND connection, the pad towards the ATMega. Drop us a line when done.

Yup, it was the GND pin on the trimpot… .
Thats the good news, the bad news is that somehow the plating has come off, so its impossible to get a clean solder joint… :S

if it’s the connection to ground you should be able to find another spot to solder to.
(with a cable)

Dunno why i didnt think of that earlier rosch ^^ (Yup, youre a genius :smiley: )
While trying to desolder the pot i somehow made a connection though, so far now im leaving it as is, should the problem return i now know where to look… Thanks guys :slight_smile:

Yeah, i am the ContrastTrimmer Master :wink:!

Glad it was so easy V’cent, have fun with your tiny mighty goddess!

Thanks a bunch fcd72 :slight_smile:
BTW : Im sooo in line for building a Shruthi-1-Programmer :smiley:

As soon as i have a working PCB Proto there will be a subscription list… stay tuned.