An electronic device has a keyboard with an internal membrane. The membrane has a set of stretch measuring strips that are configured to respond to a keystroke, as if a foldable dome collapses in contact with the membrane. The stretch gauges are connected in a Wheatstone half-bridge configuration and positioned on the membrane to limit temperature influences and a subtle bending of the membrane. The stretch gauges are also configured to increase the detection of a resistance differential when pressed on a button head with sufficient force.
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