In a message dated 12/13/2006 2:01:54 P.M. Eastern Standard Time,
[log in to unmask] writes:
have two membrane keypads that have shown intermittent "short circuit"
failures.
Hello, Carl:
OK, you've probably already looked for residual conductive ink between
conductors, but look closer for dust. Over-cured thick film conductive polymers
lose ductility and become [relatively] brittle. The "...wiggling, banging..."
you described could produce enough conductive particulate between the circuits
to yield an intermittent high-resistance short.
I'm also wondering about your dielectric: What is the dielectric material
(e.g., is it solder mask)?
ROBERT LAZZARA
VP, Business Development
T: (800) 560-9457
F: (800) 878-5566 (y servicio de mensaje espaņol)
E: [log in to unmask]
W:_ www.CircuitConnectUSA.com_ (http://www.CircuitConnectUSA.com)
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