3m Adhesive OEM SMT LEDs Membrane Switches
Product Description
3m Adhesive OEM SMT LEDs Membrane Switches
Membrane material-Polyester, polycarbonate and polyurethane typically make up the components of a membrane switch panel.
Internally, the switching mechanisms are via metal domes or conductive shorting pads.
Further enhancements include surface mount LEDs, water clear widows, dead fronts, back-lighting with optic fibre or electroluminescence and solid mounting plates.
Terminations to the PCB can be via Berg connectors and Nicomatic connectors or designed to fit Zif connectors.
Some Variables need to pay attention when design membrane keypad
The following provide insight into the considerations that need to allowed for at the initial stages of design.
As the concept develops and moves towards completion it is important to talk to experts that have a strong understanding of the variables and what impact they have on the overall product.
These following points are an example of the further considerations that should be considered and talked through with the design and sales team at Kaike Technology
Graphic overlay material options – textures, types and thickness
Graphic design and preparation – impact of colours, tones, windows, borders, embossing and shapes • Embossing options – shapes, depth and purpose
Layouts and tolerances – LED windows, gaps between LEDs, tracking and buttons. Edge shape, cutout size and hole size requirements.
Overall size of the part – material cost considerations
Tooling methods – laser cutting vs die cutting, embossing tool styles
Backlight options – Lumitex optic fibre, Electroluminescence, EL solutions
Embedding LEDs – types, size and electrical requirements. Change in overall thickness and how to manage
Clarity of any windows and impact on graphic material specifications – gloss stock with matt varnish vs textured stock with gloss varnish over windows
Membrane switch design – tracking layout, crossover requirements, pin out considerations, electrical specifications, tail length and positioning, connector type, electrical parameters, resistance tolerances
Moisture resistance and environmental considerations – gasket seals, adhesive types, environmental limitations (temperature, humidity, air pressure)
Tactile options – Metal domes, poly domes, raised surface printing, embossing.
Metal domes – sizes, shapes, force levels, durability considerations
Connector interface – pitch of tracking, resistance level of conductive silver, pin out assignment • Electrical layout and specifications – common bus vs x-y matrix, switch contact levels (under 50mA), resistance levels between 50 and 200 ohms
Rear adhesive selection – surface energy of the material being mounted to, environmental (heat, humidity, air pressure) effect that can cause separation