Customer-specific membrane keypads...the slipping of the metal domes, so increasing the quality considerably. Technical characteristics: The contact elements of our keypads are embedded

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We design and manufacture membranekeypads and front membranes to meetyour individual requirements – if neces-sary, integrated in supporting plates orpre-fitted on our enclosures.Optimal quality can be achieved forevery use on the basis of copper-laminated supporting membranes orstrip conductors applied using the silk-screen process. Depending on your needs we can sup-ply you with your own individual mem-brane keypad with fitted touch screens,displays and other electromechanicalcomponents. Printing is by means of silk-screen or

digital methods, according to the number of colours and the require-ments in respect of visual design.Our membership of the specialist keypad association ensures that weare always up-to-date with the latesttechnology, so we can always meetour customers’ needs in the best possible way. The membrane keypadproducts which we market are compo-nents and are not subject to the ElektroG (the law relating to electricaland electronic equipment and appli-ances) or to the national laws of theWEEE/RoHS. Consequently we areunder no obligation to register.

Customer-specific membrane keypads

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Mitglied in derFachgemeinschaft Tastaturen

Membrane cable

Base membrane

Switch membrane

Front membrane

We supply all standard keypads inmodified designs on request –

fast, and at low cost! Many designs are also available in"ProfiLine" technology and with an

anti-bacterial design.

Note

Distance membrane

Bonding sheet

Screening membrane (option)

Key embossing (option)

The construction of our keypads en-sures that they function very securely,and, thanks to their good chemical resistance properties, they are ideal foruse in harsh industrial environments.

Special characteristics:

• Stainless steel snap disc,gold-plated contact side

• Safety chamber for eachindividual snap disc,depending on type

• Elegant matt front membrane

• Dirt- and splash-proof according to DIN EN 60529

Base membrane using conductivesilver technology

• Graphite printing protects theconductive silver strips againstoxidation and mechanical abrasion

• Green insulation printing prevents silver migration

Base membrane copper-laminated

• The conductor strips are laminatedwith copper and galvanically silver-plated (gold-plated on request)- This prevents silver migration

and abrasion- The material is extremely flexible

and so resistant to breaking

Exactly to customers’ needs:

Size, design, colour, front membranematt, silk matt or gloss, with or with-out clear screen, with or without tactile action point – our membrane keypadsare manufactured to satisfy your exactrequirements.Depending on the type, the keypadsare equipped with a safety chamber foreach individual snap disc. This preventsthe slipping of the metal domes, soincreasing the quality considerably.

Technical characteristics:

The contact elements of our keypadsare embedded between high-qualitypolyester membranes.The contact is made by pressing onthe front membrane in the area of thekey element.On request, transparent screens (or also coloured) can be provided in thekeypad to make visible optical displayssuch as LEDs or 7-segment displays.Of course, various glasses can also bebuilt in, or the front membranes canbe left clear in the screen area.If necessary, we can fit the membranekeypads on supporting plates or onenclosures.

All dimensions in mm. Please refer to technical data.

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ProfiLine technology membrane keypads

Voltage 1-42 VCurrent max. 100 mAInsulation resistance > 100 MΩ

Bouncing time < 10 msContact elements snap disc,

gold-plated

ELECTRICAL CHARACTERISTICS:

THE MAIN ADVANTAGES:

• very good tactile feedback

• raised key element / optimal fingering

• even pressure distributionensures less wear and tear onsnap discs

• large-area keypad and contact elements can be produced

• the shape of the keys can be designed as required

• excellent value for money

Design of a standardmembrane keypad

ProfiLine technology optimises the interface between man andmachine by means of the so-called“short-stroke” feeling. A raised key element fitted betweenthe snap disc and the front membraneensures improved tactile feeling. This means that designers and designengineers can give free rein to theircreative ideas when designing individ-ual shapes and dimensions, becauseProfiLine key surfaces can be producedin almost any required or necessary sizes (ø 7 mm and over).

Whether round, square, triangular orhexagonal – the laser-cut acrylic glasskeys (recessed with front membranes)not only give the user optimal tactilefeedback, but they are also extremelysturdy. Thanks to the tough design,neither excessive pressures nor chemi-cals have any effect on the ProfiLinekeypad. If additional safety precau-tions are required, metal surfaces takecare of extensive protection.

ProfiLine, the new membrane keypad, gives the user much more than just an input element.

The sturdy, raised keys guaranteesafe operation and provide opportunities for personal and individual designs.

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Key geometry any design (round, angular, triangular, etc.)Key size (d) min. ≥ ø 6 mm / 6 x 6 mm angular /

corner radii ≥ 0,7 mmKey size max. 260 x 360 mmClearance (a) from embossing ≥ 8 mm (circular embossing)edge to embossing edge ≥ 9 mm (parallel embossing edges)Keyboard installation height approx. 1.3 mm (depending on design)Key height (h) 1-3 mm (standard: 2 mm), tolerance ± 0.1 mmActivating pressure 3-5 NOperating temperature -20° C to +70° C

(storage temperature -40° C to +80° C)Membrane material polycarbonate PC (blend)Chemical resistance (list available on request)

MECHANICAL CHARACTERISTICS:

ProfiLine´s “short-stroke” feeling

The raised key element made of recessed acrylic glass provides improved tactile feeling. And there are no limits to the individual design of the keys.


switch travel0,6 - 0,7 mm

key height1 - 3 mm

5 mm or 7 mm

ø 6 mm or 6 x 6 mm

front membraneinsert

keyboard body

h

a

d

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115 V

150 V

300 V

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0,1 0,75 2 5 10 15 20 25 30

60

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100

200 400 800 1200 1800

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Bri

gh

tnes

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Operating life (Kh)

Bri

gh

tnes

s (c

d/m

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Frequency

Increasing the voltage increasesthe brightness.The best method of increasing the bright-ness of the EL membrane is to increase thevoltage instead of the frequency. The choice of colours used for the membrane is also important. The most commoncolours are green, blue-green and white.Green and blue-green are the naturalcolours emitted by phosphorus, which means that they are the most effective.White is not a broadband colour, and isapproximately 20% darker than a compa-rable green membrane. Changing the frequency can change the colour: a higherfrequency moves the colour towards blue,and a low frequency moves it towards green.

The operating life of the EL mem-branes is extremely dependent onthe level of brightness.In use, the membranes gradually losebrightness. The industrial standard for theoperating life of EL membranes is definedas the amount of time which expires before half of the initial brightness is lost.Membranes with a high initial level ofbrightness can reach the 50% level afteronly 500 hours. Membranes which have alow initial level of brightness can achievean operating life of over 5000 hours. Thetype of AC signal used can also affect theoperating life.

Little energy is lost in the form ofheat.Normally, EL membranes are less than0.3 mm thick. This offers an advantagein comparison with sources of pointsof light, which require a 2 to 3 mmthick light guide in order to achieve asimilarly homogeneous level of lightdistribution.

As the EL membrane is normally manu-factured using the silk screen printingprocess, it is possible to producealmost any drawing or graphic as anEL membrane. The only restriction interms of design is the flat shape of themembrane.

The homogeneous light distribution ofthe background lighting is a furtheradvantage. The electro-luminescentphosphor particles are distributedevenly on the surfaces of the mem-branes. By contrast, light sources suchas LEDs or bulbs are points of light.

EL membranes emit homogeneouslight over the entire surface. Thanks to their high degree of efficiency, ELmembranes are characterized by verylow power consumption. Replacingbulbs or LEDs with EL membranes reduces power consumption by morethan 50%.

The use of EL membranes in thefield of membrane keypads offers designers many advan-tages.The benefits include low powerconsumption, low mechanicalfitting height, and mechanicalflexibility.

EL membranes • Electro-luminescence membranes

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The surface can also be illuminated selectively. If required, any section ofthe membrane can be lit separately.The brightness or level of illuminationof a membrane is the main factorwhich determines the operating conditions. EL membranes require anAC signal for operation. Increasedmembrane brightness is achieved bymeans of higher voltages or frequen-cies respectively.

In order to determine the initialbrightness, it is first necessary to establish the required lower level ofboth the brightness and the operatinglife.

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A further advantage of the Cu-lami-nated membrane is that electroniccomponents can be safely fitted withSMDs and soldered.

The logical result of this is FT-E tech-nology. Its simplicity is amazing – theinput unit (FT) and the appropriate electronics (E) are on the same carriermaterial, so there are no interference-prone and expensive connections.

Cu-laminated base membranes

The base membrane of a keypad is thelowest layer (polyester) with conductorstrips on which the snap discs for contacting are placed. BOPLA offersthe base membrane Cu-laminated andgalvanically silver-plated, and alsogold-plated if required.

The Cu-laminated material is highlyflexible, which ensures that there is nopossibility of breakage to the mem-brane cable or of silver migration orabrasion.

We offer you individual process-ing of your membrane keypadsand PCBs.

The design and manufacture of themembrane keypads takes place on networked CAD systems,which guarantees speed and accuracy.

Cu-laminated base membranes / PCBs

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PCBs with fittinge.g. connectors, LEDs, resistances

BOPLA offers low-cost manufacture of the complete membrane keypad, including PCB and fitting with simplecomponents (e.g. connectors, LEDs, resistances, etc.).

Normally, the first stage is to fit the various membrane layers and switchelements onto the PCBs. Then theexternal edges (outer profile) are milled, and if necessary, componentsare soldered onto the other side. Pinsof different lengths can be screwedinto threaded inserts which have beenpressed into the PCBs. This makes itpossible to fit additional PCBs or tofasten the complete input unit.

This construction makes it possible todispense with one supporting plate.

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Anti-microbial membrane keypads anddecor foils are primarily used in areaswhere there is a danger of infection,such as hospitals, doctors’ practices,supermarkets, canteens, buildingswhich are open to the public, andpublic transport.

The manufacturer of the foil guaran-tees correct function during the entirelifetime of the product. Autotex AM is available in thicknesses 150µ and200µ. Autotex AM does not lead toany restrictions in design – the foilscan be designed to meet customers’individual wishes.

Anti-microbial decor materialfor membrane keypads and decorfoils.

Autotex AM protects againstnumerous strains of bacteria,e.g. MRSA, salmonella spp, etc.The hard-coated polyester foilincorporates "Microban” forbuilt-in anti-microbial protec-tion. If bacteria come into contact with Microban, its anti-microbial function splitsthe cell walls of the bacteria, so preventing their growth andreproduction.

Autotex AM / PC keyboards

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PC M 301

PC M 302

PC M 56

PC A 90

PC MF 102

MM 107

MM 002

PC membrane keypads are availableon request with 2, 30, 48, 56, 61,90, 102 or 107 keys and also with a pressure point and embossing.

Decoder and connecting cable avail-able on request. The front membranesof the keypads can be designed tomeet customers’ individual wishes.

Model No. of keys DimensionsPC M 301 30 keys 128.6 x 111.6 mmPC M 302 30 keys 128.6 x 111.6 mmPC M 56 56 keys 128.6 x 111.6 mmPC MA 481 48 keys 59.0 x 159.0 mmPC MA 61 61 keys 76.0 x 210.0 mmPC A 90 90 keys 345.0 x 128.4 mmPC MF 102 102 keys 406.0 x 128.4 mmMM107 107 keys + touch pad 406.0 x 128.4 mmMM 002 2 keys + touch pad 128.4 x 101.4 mm

Membrane keypads/PC keyboards, IBM compatible

The following designs are available on request:

All listed models are available in thefollowing versions:

1.Membrane keypad: Membrane keypad only, with self-adhesive backfor customers to install in their ownequipment.

2.PC keypad for 19" installation: Membrane keypad on metal panel for installation in 19” mounting rackswith mounting bolts for electronics.

Note:IBM compatible versions for use withWindows are available. Please makethis clear when ordering!

Special designs available in "ProfiLine"technology.


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Conductive silver

Version 1 (Standard)Keypad with pressure point

Front membrane

Front membrane

Front membrane

Front membrane

Front membrane

Front membrane

Spacer (adhesive on both sides)




Spacer



Safety chamber (adhesive on top)

Safety chamber (adhesive on top)

Switch membrane

Switch membrane

Switch membrane

Switch membrane

Switch membrane

Adhesive basic layer






Version 2

Version 3

Version 4

Keypad with pressure pointand embossing

Keypad without pressure point

Keypad with pressure pointwith embossing (Mylardom indirect)

Embossed bonding sheet(ø embossing >11.4 mm)

Safety chamber (without bonding sheet)

Contact membrane

Version 5Keypad with pressure pointwith embossing (Mylardom direct)

Front membrane(contact membrane)


Switch membrane


Copper laminated

Version 1 (Standard)Keypad with pressure point

Version 2Keypad with pressure point, 2-layer

Safety chamber

Switch membrane 1(CU-laminated)

Switch membrane 2(CU-laminated)

Bonding sheet

Information

Our construction department reserves the right to carry outthe technical realisation of individual types!

LEDs

If LEDs also need to be integrated intothe keypad, the front panel must beprovided with a dimpled embossing in the area where the LEDs are to befitted.If embossing is not wanted, the key-pad can also be fitted using an addi-tional LED layer and a pad. Note thatthis method increases the total thick-ness of the keypad.

Screening membrane (option)

In order to carry off discharges of static electricity and to prevent theinfluence of spurious frequencies,screening can be built into the key-pad. This screening membrane is fittedunderneath the covering membrane;display screen with screening availableon request.

Snap discs

Snap discs or metal domes are manu-factured of stainless steel. The contactside is gold-plated. The switch opera-tion pressure of our standard snap discs is approx. 2.5 to 3 N. Dependingon the size of the domes, the mini-mum distance from the centre of onekey to the next is 16 (11) mm.

Normally the external side of thetransparent front membrane ismatt. The membrane is printed on the back, so the printing is pro-tected against environmental influences such as dirt, moisture and scratches. The front membrane,switch membrane, spacers and thebasic layer are glued together usinghigh-quality bonding sheets andcan subsquently be pressed if re-quired. Pressing of the membranekeypad is not a standard process! It is only carried out for special applications, e.g.:– increased impermeability– impermeability against alcohol

Construction

575All dimensions in mm. Please refer to technical data.

Bonding sheet (pad)BodyFront membrane

Padding keypads

Low-cost customer-specific membranekeypads can be manufactured on thebasis of our standard keypad range.

After selection of a basic keypad body,the rest of the surface is filled with aspacer. A front membrane, back-printed according to the customer’s instructions, is then fitted over thewhole construction.

The horizontal X output conductorsand the vertical Y output conductorsare connected to the contact points ofthe keys. This reduces the number ofconnections to just a few conductors.

Each key is connected to the commoncable and a strip conductor output. No additional decoding is required.All conductors are led to a highly flex-ible membrane cable in order to con-nect the entire keypad area to the electronics.

b) X-Y matrixa) Common conductor cable

Circuits

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Slot-in pockets

Slot-in pockets can be incorporated inthe keypad for the subsequent individ-ual marking of keys or surfaces.Replaceable slot-in strips (e.g. for logos) can be inserted from the side,front or rear. The slot-in pocket is fitted directly behind the front mem-brane, so the slot-in strip is visible inthe unprinted area.

Mounting holes

If components are fitted in the sup-porting plate and centered in thefront membrane, take the amount ofplay into consideration. The punched-out hole in the front membrane mustbe larger.

If the mounting drill-holes are very close to the corner of a keyboard, theresult is thin, unequal intermediatesections. In such cases, the cornershould be completely cut out.

Supporting plates

The supporting plates are manufac-tured according to customers’ specifi-cations.They can be supplied with press-inbolts with the following standard dimensions:

Our construction department reserves the right to carry outthe technical realisation of individual types!

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Dome embossing

On the dome embossingthe embossed area isabout 0.3 mm higherthan the front membrane.

Possible embossing forms:

Possible embossing forms:

Edge embossing

The edge embossing isused to guide thefingers.The niveau at frontmembrane and key arearemains the same.

Bubble embossing

The bubble embossing isin various diametersfrom 8 to 17 mmavailable.

Wart embossing for LEDs

EmbossingsMembrane cable

The position of the exit point andthe related length of the connectionmembrane should be determinedduring the planning phase. The lead-ing out of the contact connections is via the membrane cable. The ribbon is punched out of thekeypad in the area of the exit sothat the membrane cannot tearwhen it is bent. The standard grid dimension is 2.54 mm. Avoid exces-sive bending. The ideal bending radius for the cable is > 4 mm.

Plugs

The membrane cable can be led either into one membrane directplug soldered to the PCB, or a plugis crimped at the end of the cable.If plugs have been crimped in posi-tion, a single-row post plug must befitted as a counter-piece on the PCB.

Protection types

When laminating the keypad onto asupport, we recommend sealing thecable exit with a suitable adhesive.If the keypad is pressed onto the sup-ports by means of a pressing device,the keypad is absolutely waterproof(also alcohol-proof, depending onthe design).

If an enclosure used with a keypad is expected to achieve ingress pro-tection category IP 65, note the following:

1. The cable inlet in the enclosuremust be sealed with a specialadhesive.

2. It may be necessary to adaptthe construction of the keypad.

Information


External contourFront membrane / membrane keypad

The amount of play must be takeninto consideration when planning amembrane keypad / front membraneon a supporting plate or in an enclo-sure.The contour can be designed accord-ing to specific requirements.

Display glass

Glass is frequently used for screens instead of closed, clear membranes(front membranes).

The following materials can be offered:1. acrylic glass (e.g. plexiglass)2. polycarbonate (e.g. Macrolon)3. crystal glass (e.g. window glass).

Surfaces

The following roughness grades are available for the surface of the frontmembranes:1. gloss2. silk-matt3. mattMatt surfaces are used in most cases.

Protective membranes

If required, a protective membranecan be drawn over the front mem-brane or only over the screen. Thisprotective membrane can be removedwithout leaving any adhesive residuesafter the keypad has been fitted.

Releases

Before series manufacturing starts, afile will be emailed, or if preferred, apaper print-out will be sent by post forthe purpose of release.

On request, release samples will besilk-screen printed and charged for according to the work involved.

Assembly

BOPLA offers a complete range of processing and assembly services. The advantages for the customer are: faster delivery times, fewer order requirements, and a reduced risk of rejects.

In this way, the customer can be cer-tain that the keypad bonding sheetfits the various enclosure surfaces andthat there is a high level of fittingaccuracy.

Colours

Special silk screen paints for plastics –so-called key switch colours – are usedfor the printing of the front mem-branes. Printing is on the back, whichprotects the layers of paint against environmental influences. Standardpaints are selected and used accordingto RAL.

Shades of colours according to the HKS and Pantone scale can be printed.Additional costs for special colours willbe charged for according to the workinvolved.

Front membrane design

A minimum line thickness of 0.3 mmmust be kept to when the front panelis being designed. High-quality print-ing cannot be guaranteed if the linethickness is less than 0.3 mm.

For the front membrane design, CorelDRAW can be provided as a *.cdr fileand used if necessary, as can vectoredWindows data.

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Characteristics Polycarbonate PC Polyester PETPMechanical characteristics Tensile strength: good Tensile strength: good

Scratch resistance: very good Scratch resistance: very goodProcessing embossing/punching: very good Processing embossing/punching: very goodPrinting: very good Printing: very good

Electrical characteristics Penetration resistance: ø 60 kV/mm Penetration resistance: ø 250 kV/mmInsulation resistance: 109 - 1011 Ω Insulation resistance: 109 - 1011 Ω

Thermal characteristics Temperature range: - 50° C to - 120° C Temperature range: - 70° C to - 150° CMelting point: 220° C Melting point: 250° CFlammability: slow to self-extinguishing Flammability: slow to self-extinguishing

Visual characteristics Good light permeability, very suitable for Excellent light permeability, giving goodLED displays; colour reproduction slightly legibility of LED and LCD displays. Goodreduced. colour reproduction.

Chemical characteristics Polycarbonate is resistant to mineral acids, To a great extent, polyester membrane ismany organic acids, oxidation and reduction insensitive to moisture and most chemicals.agents, neutral and acid saline solutions, Polyester is resistant to detergents, water, oils, saturated aliphatic and cycloaliphatic petrol, oil, alcohol, vinegar, aliphatic hydro-hydrocarbons and alcohol, excluding methyl carbons, bleaching agents, 2% ferric chloridealcohol. solution, iodine, ethyl acetate, food colouring

engine oil; less resistant to chlorinated hydro-carbons, ketone, aromatic hydrocarbons.

NOTE: If different media come into contact with each other, the stability factors may change.For this reason, we cannot accept any liability for the details.

Characteristics and resistance of the plastic parts

Direct contact Indirect contactTechnical data Without press. point With pressure point Mylardom MylardomKey area from 10 x 10 mm from 7 x 7 mm from 9 x 9 mm, ø 9 mm from 9 x 8 mm, ø 8 mmMin. average distance between keys 12 mm 10 mm 11 mm 11 mmInstallation height approx. 1.0 mm approx. 1.0 mm approx. 0.6 mm approx. 1 mmContact surfaces depending on type conductive silver/ cond. silver/ conductive silver/ conductive silver/

graphite graphite, graphite graphitegold-plated snap discs

Switch travel (dep. on embossing) approx. 0.2 - 0.3 mm approx. 0.6 - 0.7 mm approx. 0.3 - 0.6 mm approx 0.4 - 0.6 mmSwitch pressure dep. on membrane depending on design depending on design depending on design depending on designand type of protection up to IP 65 depending on design depending on design depending on design depending on designVoltage 1 - 42 VDC 1 - 42 VDC 1 - 42 VDC 1 - 42 VDCMaximum output 0.6 W 0.6 W 0.6 W 0.6 WConductive strip resistance < 6 ohm (at 100 mm < 6 ohm (at 100 mm < 6 ohm (at 100 mm < 6 ohm (at 100 mmdepending on type length - 1 mm width) length - 1 mm width) length - 1 mm width) length - 1 mm width)Insulation resistance to front memb. ≥ 100 Mohm ≥ 100 Mohm ≥ 100 Mohm ≥ 100 MohmBouncing time (dep. on actuation) < 10 msec < 10 msec < 10 msec < 10 msecOperating life > 500 000 actuations > 1 million actuations > 300 000 actuations > 500 000 actuationsOperating temperaturefor keypads with embossing 0° C to + 45° C 0° C to + 45° C 0° C to + 45° C 0° C to + 45° Cfor keypads without embossing - 20° C to + 70° C - 20° C to + 70° C - 20° C to + 70° C - 20° C to + 70° CTransport/storage temperaturefor keypads with embossing - 30° C to + 45° C - 30° C to + 45° C - 30° C to + 45° C - 30° C to + 45° Cfor keypads without embossing - 40° C to + 80° C - 40° C to + 80° C - 40° C to + 80° C - 40° C to + 80° CBending radius membrane cable ≥ 3 mm ≥ 3 mm ≥ 3 mm ≥ 3 mm

Conductive silver membrane keypads

Information


Depending on the quality ordered andthe size of keypad, we always try to make use of the least expensive methodof production. For example, a greaternumber of panel units (see photo)would reduce the manufacturing costs if the size of orders justifies this.However, note that an increased numberof panel units will also result in highertool costs. So that we can prepare anaccurate calculation, please give usdetails of the total quantity and individ-ual batch sizes and we will prepare acost-optimised offer for you.

HINT:Make use of our inquiry check liston page 605.

Panel production

Technical data Without pressure point With pressure pointKey area from 10 x 10 mm from 10 x 10 mmMin. average distance between keys 12 mm 13 mm, 16 mm, 19 mmInstallation height approx. 1.0 mm approx. 1.0 - 1.2 mmContact surfaces depending on type copper-laminated, silver-plated copper-laminated, silver-plated or gold-

plated, gold-plated snap discsSwitch travel (dep. on design up to IP 65) 0.2 - 0.3 mm approx. 0.6 - 0.7 mmSwitch pressure dep. on membrane 1 - 3 N 3 - 5 NType of protection depending on design up to IP 65 depending on design up to IP 65Maximum voltage 42 V 42 VMaximum output 1 W 1 WConductive strip resistance* depending on type < 0.1 ohm (at 100 mm length - 1 mm width) < 0.1 ohm (at 100 mm length - 1 mm width)Insulation resistance ≥ 100 Mohm ≥ 100 MohmBouncing time (dep. on actuation) < 10 msec < 10 msecOperating life > 1 million actuations > 1 million actuationsOperating temperaturefor keypads with embossing 0° C to + 45° C 0° C to + 45° Cfor keypads without embossing - 20° C to + 70° C - 20° C to + 70° CTransport/storage temperaturefor keypads with embossing - 30° C to + 45° C - 30° C to + 45° Cfor keypads without embossing - 40° C to + 80° C - 40° C to + 80° C

Copper-laminated membrane keypads

* The conductive strip resistance is dependent on the product layout arrangement. Conductive silver bridges in CuLs technology increase conductor resistance.

Documents

Customer-specific membrane keypads...the slipping of the metal domes, so increasing the quality considerably. Technical characteristics: The contact elements of our keypads are embedded