Can I zap a 20x4 LCD just by touching its frame?

So I was wondering if there is such a thing as a static electricity shock by touching the metal frame of one of those 2004 LCD screens? Or I'm just having some other very weird problem.

I have one of those pretty standard 20x4 LCD screens, solidly mounted inside a case, working 24/7, no loose wires or anything, I have shaken the thing to oblivion and not a fizz.

BUT sometimes when I touch it, it goes blank. The back light is on, and the Arduino is on and doing it's thing too, it's just the screen that goes puff. It's a light touch, not pushing it or moving it, just a veeeerrrryyy gentle touch and boing!

I was thinking that maybe I have some static charge built up and, while I don't feel it, I'm zapping the metal frame of the LCD and that's connected to something else, which I don't see how, never seen this happening before, but who knows. Is that a thing?

Anyone had this happening before? I tried with another LCD, but since this is very random and happens once every other day, it's hard to tell if the old LCD was faulty or I'm just being lucky with the new one.

Hi.

Perhaps, i don't know for sure.
But i do think it is some other problem.
The metal frame as you called it, is an important part of your display.
It retains the contact between the electronics in the glass, and that on the PCB.
This is done using what is known as 'zebra strips', a good term to put in Google, or elastomeric connector if you like.

Use Google on that to find out what it is (so i don't have to copy that info over here).
Perhaps you need to tighten the 'frame' a bit, of course after you've read up on this.

Yes, that is very possible. At work we have a cheap 3D-printer-kit (Velleman K8200) - the controller on it uses a 20x4 Hitachi-style LCD, too.

My colleague once gave it a static shock while walking towards it and touching, and a few lines on the LCD went blank. I've checked everything and apparently the output pins on the HD44780 controller are fried. The LCD works wonderfully apart from that, just those lines are dead.

To mitigate your problem, make sure to have a good electrical connection from the LCD frame to the frame of your appliance, and if possible to a good grounded location (grounded power supply)

// Per.

Zapro:
To mitigate your problem, make sure to have a good electrical connection from the LCD frame to the frame of your appliance, and if possible to a good grounded location (grounded power supply)

I'll do that, my case is plastic, but I have earth coming in so I'll scrap the paint off the frame and run a wire to it via resistor and see how it goes.

Thanks for the info.

MAS3:
Perhaps you need to tighten the 'frame' a bit, of course after you've read up on this.

Now that I think about it, the old LCD did hit the floor one day... hmmm...

Exactly same thing happened to me today.
Last 16 characters of line 3 and line 4 are gone after my hand touched to the black metal casing. I heard the sound.

I don't know if the zapped component is the I2C backback interface or the LCD itself. I will find out when I remove this one and try with another one.

Recently I moved to a new office in one of the business towers close to my neighborhood. Since the first day I was having strong shocks everytime I touch the aluminum windows, door handles, kitchen sink. At night I can easily see the tiny lighning bolts, once it was easily 3cm no joke. Zapping some component was expected and today was the day.

I would very much appreciate any suggestions on how to prevent this, and why is it happening so much. Most of the times my fingers hurt.

Try spaying the floor with water mixed with fabric software.

May have to do this several times.

emrekocayine:
Exactly same thing happened to me today.
Last 16 characters of line 3 and line 4 are gone after my hand touched to the black metal casing. I heard the sound.

I don't know if the zapped component is the I2C backback interface or the LCD itself. I will find out when I remove this one and try with another one.
. . .

The main HD44780 controller on your LCD module contains the microcontroller and all of the memory required by your display but it can only drive 16 characters. The circuitry to drive the remaining characters is contained in four auxiliary controllers each capable of driving 16 characters. It looks like you have damaged two of them.

Don

floresta:
It looks like you have damaged two of them.

Probably just the one - they are chained.

Yes you can, ESD on LCD's is a pain in the butt full of black magic at times. If the bezel isn't tied to a ground, which most are not, the ESD will find a route, and in your case has gone through the glass into the LCD controller. I know of no off the shelf LCD that has ESD built into it expect for several of ours.

We have spent tons of hours working on ESD protection for clients, the strictest being Citrix.

Here are two videos of us testing ESD on a 2x16 Serial LCD (LK162-12), we did from 10,000V to 30,000V

ESD Hardened LCD

Standard LCD