A membrane switch consists of two polyester films screen printed with conductive ink to complete the circuit. A spacer in between two circuits, which is, die cut at contact points. The die-cut holes allow the touch of a finger to close the contact, completing the circuit. The circuit is broken when released. The panel posterior is laminated with an adhesive for mounting to a backer or enclosure and is terminated with a means for interfacing with the customer’s electronics.
This particular sample is a combination of membrane switch + silicon rubber, where Elcom has developed and manufacture such technology ahead of such product market becoming a trend in membrane switch keypad making industry.
Membrane + silicon rubber keypad/ membrane switch + silicon rubber:
1. Environmental: (1) Operating Temperature: -40°Cto+80°C (-40°to176°F). (2) Storage Temperature: -40°C to +85°C (-40°to185°F).
2. Humidity: 40°C, 90% to 95% for 240 hours.
3. Vibration: 20 G’smax.
4. Mechanical: (1) Actuation force: non-tactile 60g to 300g (2 oz to 10oz) / tactile 150g to 400g (6 oz to 14oz).
5. Switch stroke: Life expectancy: (1) Non-tactile 0.1 to 0.5mm. (2) Tactile 0.6 to 1.5mm. (3) Non-tactile > 5millionactuations. (4) Tactile > 1million actuations.
6. Electrical: (1) Operating voltage: 35volts maximum. Operating current: 10 micro amps to 100 milliamps, resistive. (2) Operating power: 1 watt maximum.
7. Circuit resistance: 10ohms to 500ohms, dependent on size and layout.
8. Insulation resistance: 100Mohms at 100VDC.
9. Dielectric withstand: >250VRMs(50-60Hz1minute).
10. Contact bounce ≦ 5milliseconds.