Holland Membrane manual

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Overlay- Top layer of a membrane switch (the graphic interface between device and user) generally made of polyester or polycarbonate.

Pad Emboss- A raised area on an overlay, which defines an entire graphic. (i.e., a full keypad of L.E.D. window.)

Proof- A paper simulation of what a screen printed overlay will look like, submitted to a customer for approval.

Polyester Dome- A keypad on a membrane that has been dome-embossed on the overlay or top circuit layer to add tactile feedback when the switch is activated. The dome shape, which is usually formed by a hydro-forming process, can vary in size and shape to achieve a desired “force” and “tactile feedback” of the keypad.

Prototype Tooling- Method of fabricating prototype components without using steel rule dies (hard tooling) allowing changes before production runs without expensive tooling charges.

Rail Emboss- A raised area on an overlay which defines the perimeter of a graphic. (i.e., perimeter of a keypad or a border.)

Schematic- A drawing showing electrical interconnections and functions of a specific circuit arrangement.

Screen Printing- Method of printing by forcing ink through a mesh selectively. This is done by closing parts of the mesh with a stencil.

Screen Tint- Area of image printed with dots so ink coverage is less than 100%, simulating shading or a lighter color.

Selective Texture- A transparent velvet finish printed on specified areas on an overlay to accentuate design elements such as windows, keypads or graphics.

Shield- A layer of polyester material that is either laminated with aluminum or printed with conductive ink to protect a switch from E.S.D. or E.M.I. interference.

S.M.D.- Surface Mount Device.

S.M.T.- Surface Mount Technology.

Specified Resistance- Maximum allowable resistance measured between two terminations whose internal switch contacts, when held closed, complete a circuit.

Sub-Surface Printing- Imaging on the back (second surface) of an overlay so the printed graphic is protected from wear by the actual material.

Tactile Ratio- A measure of tactile response.

Tactile Response- A sudden collapse or snapback of a membrane switch prior to contact closure or after contact opening.

Tactile Switch- A switch assembly that provides a tactile ratio greater than zero. Tactile switches give the user immediate physical feedback that the switch has been activated. Tactile feedback on a membrane switch can be achieved by using a stainless steel dome or a polydome construction.

Termination- How a switch is connected to the device it activates.

Translucent- Partially transparent. Having the property of diffusing light.

Transparent- Having the property of transmitting light without appreciable scattering so that objects beneath are entirely visible.

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Contents Membrane Switch Design Guide Artwork IntroductionOverlay Materials Color Matching Mechanical Tolerances Ultraviolet HardcoatsEmbossing Cosmetic InspectionESD/RFI Shielding Laser CuttingPinouts Screen Printed Flex Circuits Tail Exit PointInterconnect Domes Rigid Membrane SwitchesCreasing of Flex Circuits Loop Resistance Operating Temperature RangeActuation Force Electrical PerformanceInsertable Legends Life Cycle TestingWindows Mounting Adhesives Thick Film ResistorsEmbedded LEDs Backlighting Drawings and SpecificationsSubpanels EBA Holland Nameplate Overlay Material Guide Appendix aPinout Type of switchTail details Tail terminationWindows/Lens coating ShieldingOverlay Material Logos and special graphicsSupport panel EmbossingHydroforming Insertable legendsColor matching Switch Sealing RequirementsSwitch Venting Requirements Membrane Sample Appendix C Page Page Page Page Glossary Appendix D