To Drill or Not to Drill the LCD Displays

In this article I am talking about the consequences if you drill the LCD display (i.e. drilling out the mounting holes on a LCD module; I am not talking about off-shore drilling of oil.)

LCD’s with a PCB (printed circuit board) contain two or four mounting holes to secure the LCD module to the customer’s product. This is true for both a character LCD module and a monochrome Graphics display. The LCD’s with a PCB attached are called a “chip on board” COB display. The standard diameter of this hole is 3.5mm. Sometimes a customer needs a larger hole to accommodate a larger screw. If you have a screw that is larger than the mounting hole, it is tempting to just drill the hole large enough to fit the screw. But, before you do this, you need to be aware of the consequences.

Consequences if you drill the LCD

The danger in drilling out the mounting hole to a larger diameter is that you stand a good chance of cutting a trace. This is critical to know, because when this trace is cut, one of two things can happen.

  1. The connection between one part of the display will be severed from another part of the display; this may cause the backlight or the LCD module to stop functioning.
  2. The trace is now exposed to the environment and will allow moisture and other contaminants to come into contact with the copper. This may allow the display to continue working for some time and then after an extended period of time the LCD display module will fail. Or worse yet, become intermittent.

Solutions instead of the Drill

If you need the mounting holes to be larger, please contact Focus Display Solutions. We can redesign the PCB to accommodate any size of mounting hole that you need. There is a one-time tooling fee / NRE (Non-Recurring Engineering) that runs around $400, depending on the type and total of alterations you need. The modified circuit board, will not affect the performance of the module.

Once the customer pays the fee, they own the design and we will not sell it to anyone else without their express permission. Lead time for prototype samples of the new display will run from five to seven weeks. Note: this time frame will increase around Chinese New Year or February annually. There may be a MOQ (minimum order quantity) required for this display, check with Focus Display’s for more details.

If you have any questions regarding the mounting holes and whether or not to drill the LCD, contact Focus LCDs. You can call 480-503-4295 or simply fill out the contact form to the right of this article.