WHAT IS MEMBRANE SWITCH?
The membrane switch is a momentary switching device that is manufactured by using a series of flexible layers of polymer films and adhesives. The top layer, called a graphic overlay, is manufactured by printing on the down surface of transparent polyester or polycarbonate film. Membrane switches can be constructed of multiple circuit layers, and more optimized graphic design features, such as domed key embossing. Designs that are more complex require more material layers for proper construction and reliable operation. Membrane switches, when combined with components such as a tactile dome, graphic overlay, or integrated LEDs or resistors can provide the designer with virtually limitless capabilities to create the ideal custom user interface for their products.
Membrane switches have been a critical component in connecting customers or end-users to your machines for over 20 years. As a leading-edge custom membrane keypad manufacturer, C.N.Nameplate Co produces custom membrane switches, membrane keypads and keyboards, and tactile membrane keypads, which are tailored to your exact requirements. Our design engineers work closely with you, offering advice and support to create a membrane switch design that will meet your functional, cosmetic, cost and delivery criteria.
How Are Membrane Switches Constructed?
1.Graphic Overlay – PET/PC is usually the material of choice due to its fantastic chemical resistance and flex property . UNIGREAT can do digital printing, screen-printing, or apply both methods to ensure you get the right colors, textures and finish your design requirements.
2.Overlay Adhesive – This adhesive layer stick the graphic overlay to the top circuit layer, and is usually an acrylic adhesive. The material is same with the fourth layer. Only the thickness maybe different according to the actual situation.
3.Top Circuit Layer – The material of this layer is specific. Is is a 0.1mm thickness thermostable PET film printed with conductive silver ink and also dielectric oil, which used for fastening metal domes.
4.Circuit Spacer – This layer separates the top circuit from the bottom circuit so that switch remains normally break until the keypad is pressed. The circuit spacer is a polyester spacer with adhesive on both sides.
5.Lower Circuit Layer – This layer is a 0.1mm–0.25mm thickness thermostable PET film printed with conductive silver ink and also dielectric oil. This layer terminates as a flexible tail that serves as an interconnector to controller PCBs or other IC.
6.Rear Adhesive – This adhesive layer bonds the entire membrane switch to the product surface, housing, or to a rigid support panel. CNNAMEPLATE can use the proper adhesive type and thickness to bond your membrane switch to your equipment.
Features & benefits of membrane switches
1. Good durability The service life of membrane switch can reach more than one million times. Since the switch action is only realized by the vertical spring of the elastic film, the creep amplitude is very small, which is only 0.1-0.3 mm, and the material selection is reasonable, which is far from reaching the yield limit of the film. Therefore, the film material can withstand more than one million times of use without deformation.
Specification:
Environmental | Operating Tem | From -20 to 65 °C/ -4 to 149 °F |
Storage Tem | From -40 to 85 °C/ -40 to 185 °F | |
Seal | 3M permanent acrylic adhesive resists against dust, water, oil and moisture conditions. | |
Special sealing options are available for wet environments. | ||
Mechanical | Travel | .007 inches to .015 inches |
Operating Force | 4oz to 8oz | |
Electrical | Operating Voltage | 30 volts maximum |
Operating Current | 10 microamps to 100 milliamps, resistive | |
Closed Circuit Resistance | 100 ohms typical, dependent on size and layout | |
Open Circuit Resistance | 10 megohms | |
Operating Power | 1 watt maximum | |
Circuitry | X-Y matrix or one side common |