I am looking for some guidance on the following construction: We have a remote control panel that contains an LCD display (approx. 2" x 1") mounted on a circuit board behind a metal panel. An opening in the metal panel allows the user to see the screen, and is only marginally larger than the display. Over the metal panel is a laminated label containing some membrane switches. All the circuit traces for the membrane switches are approx. 1/2" or more from the edges of the label, and are contained in the bottom layer of the label (ie one layer of plastic between them and the metal panel). The ribbon cable from the membrane switch to the pwb is routed through a hole in the metal panel. There is a clear plastic window in the label allowing viewing of the LCD and that window is more or less touching the glass face of the LCD display. We don't want to recess the LCD because of viewing angle problems.
We are subject to 8kV air discharge and 6kV contact discharge. 1. Does this construction sound like an ESD test failure waiting to happen? 2. Does it make any difference whether or not there is an air space between the clear plastic window in the label and the glass face of the LCD display? Should we recess the LCD, and if so, by how much? 3. Are there preferred materials for any of the layers of the membrane switch label? 4. Any hints anyone? Any help will be greatly appreciated. Thanks, Jim Eichner Statpower Technologies Corporation jeich...@statpower.com Any opinions expressed are those of my invisible friend
