Author Topic: Static Discharge recommendation  (Read 417 times)

Virginia Controls

  • Newbie
  • *
  • Posts: 2
  • Karma: 0
    • View Profile
Static Discharge recommendation
« on: January 21, 2019, 12:53:23 PM »
We use the ND-0420DZ-FSW-FBW in our product.  We have accidentally 'zapped' 4 displays with electrostatic charges (ESD) recently that cause the displays to either go blank or show random streaks through the display.  What is the ESD rating on the display and is there anywhere on the display that can be grounded to make is less sensitive to ESD?

Virginia Controls

  • Newbie
  • *
  • Posts: 2
  • Karma: 0
    • View Profile
Re: Static Discharge recommendation
« Reply #1 on: January 21, 2019, 01:19:00 PM »
In answering my own question, I found New Haven's Handling Procedures document - which appropriately warns of the ESD sensitivity of CMOS components.  I get that.  What I am looking for is suggestions on how I can improve the displays protection against ESD when it is shipped to customers who will most likely not have an ESD program in place.

I personally have zapped 3 displays by touching them with my knuckle on the lower right edge of the PC board (we have a keypad mounted right below the display, so it is easy to accidentally touch the display.)

Somewhere on New Haven's website, there is a reference to Elwood Controls who makes bezels for the displays.  I contacted them, but we could not agree on how to design a custom bezel to completely cover this particular display.  This issue is made worse by the fact that the NHD drawing in the data sheet does not exactly match the actual display.  The back light panel is longer than the drawing shows and the back light LED leads wrap around the right edge of the PC board instead of going through the PC board.

Alee_S

  • Administrator
  • Jr. Member
  • *****
  • Posts: 40
  • Karma: 0
    • View Profile
Re: Static Discharge recommendation
« Reply #2 on: January 28, 2019, 10:54:31 AM »
Hi there!

You may find the ESD ratings for the displays under our 'Quality Information' table located on Pg. 12 of the displays datasheet.
Datasheet: http://www.newhavendisplay.com/specs/NHD-0420DZ-FSW-FBW.pdf

To limit ESD effects to the display, you may solder the J6 jumper pads located on the back of the display (Please see red box on image below). By soldering J6 together, the bezel tabs that are making contact with the metal pads will now be internally connected to ground of the display. This will allow any ESD a safe path to dissipate to ground without "zapping" the display.

 

Static discharge killing LCD

Started by peteralieber@gmail.comBoard Character LCDs

Replies: 5
Views: 5009
Last post April 22, 2015, 11:32:25 AM
by Michael_L