Products

Types

TYPES OF SILICONE MEMBRANE AVAILABLE

Standard silicone membrane with integrated conductive pills: When the key is actuated the conductive pill bridges the circuit pad traces and makes contact, the circuit is then closed. The base circuit could be either a screen printed circuit (conductive silver on polyester), Kapton flex or a rigid PCB.

  • Characteristics:
    • Number of contacts: Estimated at 5 million +
    • Contact resistance: Lower than 200 Ohms
    • Diameter of the pills: 2mm, 2.5mm, 3mm, 3.5mm, 4mm or 5mm.
    • Typical thickness of the pills: 0.5mm (this should be taken into consideration when the stroke of the switch is determined)
    • One or more carbon pills can be used by key, depending on the geometry of the key


Tactile membrane with conductive pills

Non tactile membrane with conductive pills

Note: The configuration of the WEB design of the two examples above is presented only as an example. GGI International will determine the adequate web design for your specific application.

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Silicone Membrane / Polydome assembly: In this added value application, electrical contact is performed by the screen printed conductive silver/carbon shorting pad on the bottom side of the formed polyester polydome switch. The electrical contact is carried out by the displacement of the printed polydome on the circuit. This construction may be used for designs requiring very small keys.

   

Silicone Membrane / Metal dome assembly: In this added value application, the contact is performed by a stainless steel nickel plated metal dome placed between the silicone key and the circuit. The mechanical performance of the keys is the result of the collapsing of the dome combined with the parameters and the geometry of the silicone actuator. This type of application is more effective thanks to the combination of these two technologies. The electrical specifications of the key are dictated by the characteristics of the dome and the type of circuit used (screen printed conductive silver on polyester, Kapton flex or a rigid PCB).

   

Silicone Membrane / Pushgate Assembly: In this added value application, the contact is performed by a Pushgate armature placed between the silicone key and the circuit. There are two options for the size of the Pushgate: 0.625" or 0.406". The choice of armature is made according to the dimensions of the keys. This switch provides a consistent tactile and audible feedback across the switch matrix and is rated at well over 10 million actuations making it one of the most reliable switch technologies in today's marketplace. There is no wear on the armature; it is the magnet layer that does the work.

   

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