What Is A Membrane Switch?

A membrane switch is used in different electronic products. It functions as an on-and-off circuit, similar to mechanical types, but is made from a circuit. It is a modern version of the mechanical types and is already being used in products like microwave ovens, remote controllers and others. These switches are now preferred over the traditional one as it comes with customizable options. There are emerging companies that can offer membrane switch for different purposes.

How It Is Constructed

The American Society for Testing and Materials (ASTM) defines this switch as “a momentary switch device in which at least one contact is on, or made of, a flexible substrate.” It is usually made up of four layers but some products require more. Each layer has a distinct function so assembling and installing each layer needs careful handling.

The first layer is called the graphic interface. It is located at the topmost layer of the membrane switch, the one visible to the naked eye. It functions as the receiver in which the user can press down a certain button for a specific action. The printed circuit is another layer. It is where the electronic signals are sent to complete the action. This layer is made out of conductors like copper and other polyimide substances. Each layer has to be installed in pressure-sensitive process as it has a huge effect on the over-all function of the switch. In some cases, the switch is installed with keyboard housing for practical purposes.

Backlighting

There are three ways on how the membrane switch is installed with a backlight. The first one is by using LED. LED is short for Light Emitting Diodes, usually seen in many commercial areas. LED is usually installed as indicator lights since it emits a bright light.

Optical fiber is also used in combination to LED. This is the ideal lighting if the membranes switch is prone to humidity and changes in temperature. The third option is to install EL, or electroluminescent lamps. These are more affordable than the two lighting and it allows flexibility in terms of color variation. However, it can only emit light for up to 8000 hours. This is way different when compared to the optical fiber which can go for up to 100,000 hours.

Practical Applications

As mentioned above, are used in many electronic devices. These include air conditioners, television remote control, ovens, toys and many more. These switches are now used due to the many advantages it offers such as easy clean-up and maintenance. Membrane switches can be easily cleaned with the use of dry cloth. The dust can be wiped away as the outer layer is made up of solid plastic. Aside from that, it is sealed appropriately so that no other substances can penetrate into the electric circuits.