DIY Custom Membrane Keypads and Switches Design

If you are searching an article where you may learn DIY Custom Membrane Keypads or switches design from a Professional Keypad Manufacturer like us, then you are at a right spot! We play with membrane keypads daily, so be rest assured that your DIY membrane keypad will work great with us. Just check the image below of a standard membrane keypad used for a handheld device. Does not it suit well on that tiny device? Great color combination, suitable surface of the keypad, low profile, thin and lightweight and many other factors contribute to the success of Membrane Keypad!

DIY Membrane Keypad design

That sounds cool, but how do we start? Looking at the image above you may think that DIY Keypads are difficult to make, but we will make it very simple for you. Did you know keypads are favorite amongst product designers due to the features mentioned above and they are relatively cheap when compared to other HMI or input devices?

The membrane keypad in the image above is a 45x25mm small size membrane keypad, and there are big ones too and the costs are proportional to the size of the keypad. Custom membrane keypad considers every parameter before going into manufacturing, for example the placement of keys, the graphic overlay material, color combinations, the force exerted on the keys, the flexible tail connection, the connector type and what not.

Parts of DIY Membrane Keypad

You must be wondering, what goes inside the keypad. This curiosity prevails among many electronics enthusiasts and that’s the reason we have shown the layers across the keypads in image below:

Layers of Membrane Keypad - Graphic Overlay, Flexible Printed Circuit, Metal Dome Layer
From (L-R): Membrane Keypad Overlay, Flexible Printed Circuit, Metal Dome Layer

There are three main parts (layers) of any membrane keypads:

1.      Flexible Printed Circuit (FPC) of DIY Membrane Keypad:

As you can see in the image above, we have a FPC manufactured at Linepro’s FPC Facility. The circuit has conductive traces on both sides of the layer. The traces accumulate at one common extended point of the circuit which we call as ‘Flex tail’. The flex tail has a suitable connector which can be integrated with the microcontroller.

You can get these circuits manufactured from us: just send us your circuit layout details and we will do the rest. If you want your circuit layout be designed by us, we can do it for you too! We have all-under-one-roof modern manufacturing facility; want a tour across our facility? Check our Corporate Video.

2.      Vinyl Decal or Frontal Graphic Overlay:

Graphic Overlays are product of base material polyester or polyethylene or polycarbonate, it depends on the working condition where the keypad is being put to work. You can always take a consultation from your manufacturer on the material most suitable for your application, but in general sense, polyester is more durable especially for a non-tactile type of keypad. Polyester has better chemical and UV exposure capacity compared to other materials.

Read our blog on: Facts about Graphic Overlay material for Membrane Keypads

3.      Tactile and Non-tactile layer

As you can see in image above, tactile membrane keypads have an array of metal domes inside them. Tactile keypads come in various dimensions depending on the nature of force exerted on the keypad and the reciprocal effect it returns in form of click to the user. As you can see in image below, these are domes from a reputed company named Snaptron. Tactile keypads are peculiar in returning feedbacks as they completely eliminate requirement of beep system or lighting to tell user that the input or press has been recorded. Instead, the domes after a press pop-up back, which ensures the user of the input being recorded.

In contrast to tactile keypads, we have what is popularly known as Non-tactile keypads. Unlike tactile keypads, tactile keypads are silent operating keypads with no essence of a click! They are cheap when compared to tactile keypads as they do not possess domes in them. They are more reliable than tactile keypads due to the fact they do not contain mechanical part like domes.

Read our blog: Tactile and Non-tactile Feedback Systems in Input Devices

Design of Membrane Keypads

Let us look at how cheap they are and how to design Membrane Keypads and send relevant detail files to manufacturer.

Membrane Keypad circuit diagram, Bill of material, dimensions

So how to design membrane keypads, it turns out to be very easy and you can use any software package available or let’s put it this way that – you can prepare the schematic on a kitchen napkin and send a snap of it to your manufacturer! Trust us, it’s that simple! It only takes a general idea of what you want of membrane keypad for the manufacturer to understand the scenario.  In this particular case, as shown in the image above (you need not be so very specific with your manufacturer) you can mention the tactile switch type and how many grams of force would be applied, the adhesive make, type of dome, make of dome, the graphic overlay material, operation temperature and the connection method or connector type.

Free Membrane Keypad and switches design guide
Click the Link below to get the Membrane Keypad design Guide on your Email

What’s Inside the Free Membrane Keypad Design Guide?

Read the Membrane Keypad Design Guide to know the design and manufacturing considerations at Linepro. Get to know some fundamental yet ignored considerations by other manufacturers which are taken care off at Linepro.

  • The entire design process of Keypads at Linepro
  • Considerations for Graphic Overlay such as material, windows, printing methods and embossing
  • Circuit Considerations
  • Backlighting Considerations e.g. EL Lamp, LEDs, optical fibers
  • Electrical and Mechanical Specifications
  • Actuation Force Design Considerations
  • Shielding Options
  • Dome Selection for Tactile Feedback

The Membrane Keypad Design Guide is ready for you. Just click the link below and get the Free Membrane Keypad Design Guide on your Email!

Get the Free Membrane Keypad Design Guide

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