Membrane switches are characterized by the use of a flexible substrate on which contact is made. Not to be confused with a mechanical switch, they are typically made using a conductive ink like copper, silver or graphite. They are often preferred over mechanical switches because of their low profile and slim design. However, membrane switches are designed in a variety of back panels, some of which we’re going to explore in this blog post today.
The majority of membrane switches are designed with aluminum back panels. This lightweight and durable metal offers an unmatched level of versatility while also reducing the total cost of construction. Furthermore, aluminum back panels support designs like painting on top, which is another reason why they are preferred.
Another type of back panel used in membrane switches is steel. Steel is generally heavier and somewhat stronger than its aluminum counterpart. By itself, however, steel is somewhat susceptible to rust and corrosion. And once rust begins to form on the back panel, it can deteriorate the membrane switch and its electrical components. To prevent this from happening, manufacturers of membrane switches often coat their steel back panels in a corrosion-resistant material, such as chromium. Adding just a small amount of chromium essentially creates stainless steel; thus, protecting the back panel from rust and corrosion.
An alternative to metal back panels is plastic injected molded cases. In this design, the back panels feature a molded shape that contours to the membrane switch so it can be straight against the surface. They are typically used in medical equipment, though plastic injected back panels can be used in other applications as well.
Finally, circuit board back panels are used for membrane switches that require a lightweight design, such as phones and radios. In this design, the back panel actually contains the necessary circuitry for the switch; thus, allowing for a smaller and slimmer design. All membrane switches boast a compact design, but those made with a circuit board back panel are particularly effective in this regard.
These are just a few of the most common back panels used in membrane switches. Of course, there’s no single best type, as it varies depending on the specific application. When choosing a back panel, familiarize yourself with the different types and select the one that best meets your needs.