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NHD-2.7-12864UMY3 - VDD short to VSS

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I've been using an NHD-2.7-12864UMY3 to do a bunch of prototyping and I think I've managed to cause an electrical issue with it.  With the display not connected to anything, there is a short between VDD (pin 2) and VSS (at any VSS point on the display PCB).  Resistance is about 45 ohms.  I've visually inspected everything, but I don't see anything obviously wrong.

Is there any way for me to trouble shoot this (schematic available?)

Anyone have any ideas?  Does New Haven participate in the forum?

VDD and VSS, of course, should not be shorted.  I am not sure what testing you have performed that has caused this, but I'm sorry a schematic is unavailable.
My guess would be possibly try replacing one of the decoupling capacitors C1/C2, or at at least checking there is no solder-short present there, or anywhere else for that matter.
Otherwise, you can order another display to replace the one you have damaged.

Just a follow up.  I removed C1 and C2 and the short still persists.  I did find a few interesting things with further testing.  With 3.3VDC applied to pin 2 and pin 1 connected to ground on the power supply, I was able to consistently measure 45mV on all ground points.  Additionally, as soon as I connect the display to 3.3VDC, the voltage displayed on my multimeter drops to .74VDC.  As I probed around the display PCB, occasionally I would see 2+VDC where I should see 3.3VDC, but it would just be a fleeting reading, then drop to .74VDC.  Putting the scope on various points did not show anything of interest - no ripple, no AC, etc. 

One other interesting point is using my multimeter to check continuity, on the tone setting, produced a clear steady tone anywhere on the ground circuits (with the negative lead connected to pin 2).  However, when I put the positive probe onto any part of the 3.3v circuit, it produced a buzzing tone.  Not sure what that means or if it's even of interest. 

I also checked all the components closely under magnification and did not see any that appeared to be burned.  I guess at this point, I'm going to write off this display and purchase another.  Unless someone has any other ideas.

It looks like U1 is the problem.  I couldn't read the marking on it.  Can anyone tell me what this device is so I can replace it?  On a NHD-2.7-12864UCY, the same device (U4) is only marked BLCVA and I can't find any info on that.


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