Anti-Chemical Membrane Front Control Micro Switch Pannel
Product Description
Kaike manufacture high-performance, high-quality, and highly durable Membrane Switches for the medical device, military, automotive, marine, and OEM industries since 2003.
Membrane Switch Description
A Membrane Switch is an electrical switch that is used to activate and de-activate an electrical circuit, turning it on or off. They are typically used to communicate a user’s command to the electronic device in order to perform a desired function. The circuit actuation is usually performed by pressing a specific location on the user interface, known as the Graphic Overlay, thus closing the circuit within the printed electronics below. When the membrane switch key is released, the circuit poles separate, and the circuit returns back to an open state.
A typical Membrane Switch construction is comprised of a central thin film membrane layer. This film is typically made using a Polyester material, although there are a wide range of other material options that can provide added benefits for more extreme environments. The circuitry is constructed using a series of printed conductive inks. It is within this process that separates a Membrane Switch from a Copper etched Printed Circuit Board and other mechanical electronics. The use of printed conductive inks provides the greater cost advantage as well as reduced development and lead time from its copper etched cousin. There are several different circuit actuation types that can be incorporated into a Membrane Switch from flat non-tactile keys, metal domes for a tactile and audible response, Polyester formed domes as well as capacitive options. Other electronic components can be mounted into a Membrane Switch as well for added functionality. Low profile LEDs, resistors, and capacitors can be integrated into the circuit construction providing more enhanced user feedback options.
Membrane Switch Applications:
Household appliances (i.e., air conditioner control panel, TV remote control, microwave oven panel...)
Medical equipment
Control panel-oriented industrial and manufacturing equipment
Military equipment
Aerospace applications
Automotive controls and panels
Retail and consumer-related equipment or machines (i.e., exercise equipment, vending machines, gasoline pumps, etc.)
Construction of Membrane Switch:
Graphic Overlay
Overlay adhesive/gasket
ESD shielding layer (optional)
Dome retainer and/or circuit spacer
Surface mounted components (optional)
Circuit layer
Rear adhesive layer (with liner)
Back panel
Membrane Switch Features:
Custom printed graphics and logos (Graphic Overlay portion)
Custom shapes
Multi-layer/sided construction through conductive vias
Back-lighting
Surface texture materials (Graphic Overlay portion)
Embossing (Graphic Overlay portion)
Actuation options (tactile metal dome, polydome, flat non-tactile, and capacitive options)
Customizable connector styles
Window lens coating (Graphic Overlay portion)
Moisture and dust-resistant sealing
LED/resistor embedding
Solution for EMI/ESD/RFI shielding
Other solutions available for custom Membrane Switches upon request
Membrne Switch Material
The most common overlay materials are either Polyester or Polycarbonate. Polyester has a longer wear-life (greater than 100,000 actuation cycles) and it has greater chemical stability. Polycarbonate shows wear at around 50,000 actuation cycles, although it is still popular because of its lower cost, high clarity and its ease of printing and diecutting. Both types of materials are available in different texture finishes and also high gloss. Certain designs requiring selective texture, can also be accommodated using texture or gloss printable ink. Hardcoating is also available for applications requiring scratch-proof.
Polyester film is available from Autotype and the following material are most commonly used:
Autoflex EB
Hard coated PET
Available in gloss or antiglare finish
High abrasion, chemical and solvent resistance
Can be embossed
Autotex
Textured PET
Available in Fine or Velvet textures
Can be embossed
High abrasion, chemical and solvent resistance
Long flex life
Can have selective gloss windows
Autotex XE
Available in Fine or Velvet textures
Same as Autotex but for outdoor use, and resistant to yellowing an becoming brittle in outdoor UV light
Autotex AM
Available in Fine texture
Same as Autotex but with the added benefit of an antimicrobial coating on the surface
Polycarbonate film:
Lexan HP92S (coated film)
High performance, easily printed and diecut
High gloss polished surface (92 % light transmission)
Hard coated and shows strong durability to typical household chemicals
High abrasion resistance (4 delta haze on Taber abrasion test)
Pencil hardness HB-F
Available in gauges between 175 micron to 750 micron
Lexan OQ92S (coated film)
Offers good optical, good chemical, abrasion and UV resistance over the standard HP92W
Lexan HP92W (Coated film)
Has a very good chemical and abrasion resistance, but with good UV resistance also. Used for outdoors
Lexan OQ6DA (coated film)
Hardcoated PC/PMMA film
4H pencil hardness
Excellent chemical resistance and impact resistance
Excellent light transmission
Rigid Membrane Switch
Membrane switches can be built with a rigid PCB. When many components such as LED, resistors, IC are needed, we recommend a PCB combined with a membrane switch flexible layer.
Electrican Performance of membrane switch panels
Loop resistance: 100 Ohms
Open circuit resistance: 50 MegaOhms Minimum
Contact Rating: 100 mA at 28 VDC
Maximum Load: 1.5 VA nominal
Contact Bounce: 5 milliseconds
Operating Temperature: -45C to 75C