design guide - short version - n&h technology
TRANSCRIPT
![Page 1: Design Guide - Short Version - N&H Technology](https://reader031.vdocuments.net/reader031/viewer/2022020706/61fc9f969d50e757a521c6f4/html5/thumbnails/1.jpg)
Silicone Rubber Keypad
Engineering in Germany - Production in East Asia
N&H Technology GmbH
Single Source Supply
Import & Export of Industrial Products | Technical Support and Engineering | Business Consulting and Representation
Design Guide - Short Version
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Technical Types
Keypads with Contact Pills Multi Moulding Colours Translucent material for Night Design with positive and negative printing
Laser Engraving on rubber keys for Night Design
Laser Engraving on plastic caps for Night Design
Keypads with Polydome and Metaldome
Silver painted or Chrome plated surface
Keytop with Epoxy Coating IMD film technique
P+R technique Rubber with plastic keys Rubber and plastic keys with integrated Light Guide
Integrated EL and LED Backlight Metall keys with backlighted legends
Singel Keys
Technical Types
N&H Technology GmbH +49 (0)2154 - 8125-0 [email protected]
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Design Rules
Terminology
Dimensions
A-a ³ 0.4 mmB-b ³ 0.4 mma-d ³ 1.5 mmc-a » 2.0 mmH ³ s + 0.4 mmp-s ³ 0.15 mmR > re » 0.8 - 1.2 mmf ³ g / 2I ³ 1.2 mmk ³ 1.5 mmm ³ 0.6 mmn ³ 1.0 mmr ³ 0.4 mm (R)t ³ 0.3 mm (R)
a ³ 1.0 mm (R)b ³ 0.5 mm (R)c ³ 2.0 mmd ³ 1.2 mme ³ 1.5 mm (Ø)f ³ 2.0 mmg » 1.0 mm wide; 0.3 mm deeph ³ 2.0 mmi ³ 1.5 mm
In applications where the keypad is completely sealed, Guide Holes are not allowed and air venting can beachieved through venting paths between keys, i.e. the air vents should not lead to outer edge of keypad.
N&H Technology GmbH +49 (0)2154 - 8125-0 [email protected]
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Force [cN]
Travel [mm]S1 S2 S4
F1
F4
F2
F3
F1: Actuation forceF2: Contact force ( mechanical contact )F3: Return forceF4: Over stroke force ( electrical contact )S1: Peak travelS2: Contact strokeS4: Over stroke
Push curve
Return curve
Snap Ratio = F1-F2 x 100% F1
Force-Travel Diagram
The force drop from F1 to F2 yields Tactile Feeling. The higher the Snap Ratio, the stronger the Tactile Feeling. On the other hand, a higher Snap Ratio means a lower Return Force F3 which could cause Key Jamming.In the case of Polydomes or Metaldomes, the Tactile Feeling is concise and strong although the Snap Ratio is nominal low, because the force drop is rapid and the curve of the force drop is steep.
Key Shapes and Characteristics
Design Rules
4N&H Technology GmbH +49 (0)2154 - 8125-0 [email protected]
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Design Rules
Legends and Night Design
Positive Printing Negative Printing
Printed legend
Material colour
Printed keytop
Legend with material colour
Margin of keytop edge
Margin 0.5 + 0.15mm min.
Legend off-centre: + 0.3 mmLine width: > 0.2 mm
Through application of transmissive material the keytop and the key flank can be backlighted.
The legend, the margin of the keytop edge and the key flank are illuminated by use of transmissive material.
Laser Engraving Legends
The surface paint of legend area is evaporated by applying a laser beam. The basic paint, which makes up the legendcolour, is a light transmissive layer, whereas the surface paint is impermeable to light. If the basic paint is omitted, the keymaterial colour forms the legend colour.
In order to eliminate the dark colour of the Carbon Contact, which is visible through translucent silicone rubber, thecontact area can be pre-printed white before Carbon Dip Printing, or optionally Carbon Pills printed white on one side canbe used.
Illumination Options
Centre LED Illumination
EL Backlight
Side LED Mounting
Light Guide Integration
Translucent silicone rubber
Basic Paint for legend
Surface paint
Translucent silicone rubber
Basic paint for legend
Transparent plastic cap
Surface paint
Translucent silicone rubber
LED
Translucent silicone rubber
Translucent silicone rubber
PCB
Electroluminescent lamp (EL)
Light impermeable
Light pipe
LED
Bezel
LED
N&H Technology GmbH +49 (0)2154 - 8125-0 [email protected]
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Electrical Contact
Design Shape
Circular Circular Ring Semi-Circular Ring Oval Square Square Ring Semi-Square Ring
Contact Type
Contact Surface of PCB: Gold Carbon GoldType Contact Shape Contact Resistance Max. Rating Life Cycles
Carbon Dip Printing no limit 150 - 300 Ω < 600 Ω 30 VDC / 3 mA 1-3 MioCarbon Pill circular < 100 Ω < 200 Ω 30 VDC / 5 mA > 5 MioLow Resistance Carbon Pill circular < 10 Ω < 30 Ω 30 VDC / 5 mA > 5 MioPolydome circular 1 - 10 Ω < 30 Ω 42 VDC / 20 mA > 1 MioMetal Powder Pill circular 10 - 50 Ω < 100 Ω 30 VDC / 30 mA 1 - 5 MioMetal Pill circular 1 - 5 Ω < 20 Ω 100 VDC / 100 mA > 5 MioMetaldome circular, square, oval 1 - 5 Ω < 30 Ω 42 VDC / 30 mA > 1 Mio
Standard Size of Carbon Pill
Carbon pills are usually circular from Ø 2.5 mm to Ø 8.0 mm with step 0.5 mm. Other diameters and shapes are possiblewith more costs involved.
PCB Contact Surface Options
PCB Contact Surface Material Contact Surface
Rigid FR4, CEM1, etc. Gold, Nickel, Carbon
Flexible Polyimide Gold, Nickel
Flexible Polyester Carbon, Silver, Carbon-Silver-Mixture
For high reliability applications Gold plated PCB is preferred. Silkscreen printed carbon is the most commonly used platingbecause of low cost and high chemical resistance.
PCB Circuit Type
The PCB Contact Area in each direction should be 0.5 mm min. larger than the Contact Area of keypad.For Rocker Key and Keys with Metaldomes, please send PCB Contact Circuit to N&H for approval.
Gold Traces Carbon Traces
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Design Rules
N&H Technology GmbH +49 (0)2154 - 8125-0 [email protected]
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Design Rules
Technical Options of Keypads
Silicone Rubber with Polydome Silicone Rubber with Metaldome
Silicone rubber
Foil
Metaldome
Silicone rubber
Embossed Polyester dome
Silicone Rubber with Snap-on Plastic Caps
Silicone Rubber withfree floating Plastic Caps
Plastic cap Plastic cap
Silicone rubber Silicone rubber
Bezel
P+R Technique Plastic Cap with Light Guide
Necessary preloading of the keytop throughplastic cap: 0.1-0.2 mm
Plastic top, glued or injected
Legend layer possible
Silicone rubber
Plastic cap with Light Guide
PC Light Guide double shot or sequence shot
Silicone rubber
Silicone Rubber with Snap-on Plastic Caps
Silicone Rubber withfree floating Plastic Caps
Foil transparent
Legend colour
Key colour(negative legend printing on the back of foil)
Silicone rubber
Polydome or metaldome
PCB
Legend colour
Key colour(negative legend printing on the back of foil)
PC pin
Polydome or metaldome
PCB
N&H Technology GmbH +49 (0)2154 - 8125-0 [email protected]
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