How Do Membrane Switches Work?

What exactly are membrane switches and how they work? Whilst at first this concept can be a little hard to get your head around, it is actually a lot simpler than it seems. This type of electronic switch plays a vital role in most modern devices including your watches, microwaves and even television remote controls. Below, we simplify for you what exactly membrane switches are and how they work.

The Basics of Membrane Switches

To start off, let’s look at what exactly membrane switches are; a membrane switch is an electrical switch that can be used to either turn on or turn off circuits. This allows you to communicate with a device by giving it commands. They are widely used in keypads, toggle switches and keyboards.

Why Are They Better Than Mechanical Switches?

Mechanical switches and membrane switches are not the same thing. Whilst they both share some similarities as to their purpose and how they function, there is one big difference between them. With a mechanical switch, you will normally find that it is made of copper and plastic. Copper is conductive, while plastic is resistive.  Membrane switches, are instead, made of indium tin oxide or polyethylene terephthalate.

How They Are Constructed

This will vary from manufacturer to manufacturer as each will have different specifications. What’s more, each different type of membrane switch will be constructed differently. For the most part, you will find that they are made up of four layers with the top layer being the graphic interface or display. Below this is the printed circuit made usually of copper and polyimide. Each layer is built with pressure-sensing adhesives and the keyboard housing is what holds it together.

The Back Lighting of a Membrane Switch

With membrane switches, you tend to find that they will contain one of three different backlighting methods. The first option is light-emitting diodes which are also known as LEDs. The second option is optical fibres, while the third option is electroluminescent lamps which are also known as EL. These backlights will illuminate the interface which allows you to be better able to see what you are doing.

Membrane switches are a fantastic investment and go hand in hand when upgrading your membrane keyboards and membrane keypads.