Membrane switches have become an increasingly popular alternative to mechanical switches. Like all electrical switches, they are designed to control a circuit. Pressing the membrane switch completes the circuit, whereas releasing it breaks the circuit. With that said, membrane switches are designed with one or more flexible contacts. The presence of flexible contacts — as opposed to rigid contacts — offers several unique benefits, some of which include the following.
#1) They Contain Metallic Ink
Most types of membrane switches are constructed with printed circuits featuring metallic ink. Copper, silver and graphite, for instance, are commonly used to create the ink for membrane switches. All three of these metals are electrically conductive, making them an effective choice for printed circuits. With copper, silver or graphite ink, electricity can flow through the membrane switch’s printed circuit.
#2) Sealed Design
Thanks to their sealed design, you’ll often find membrane switches used in humid environments. The outer surface is sealed to prevent the intrusion of moisture, liquids, dust and other contaminants. While other types of electrical switches are susceptible to contaminants, membrane switches are not. Their sealed design offers a high level of protection against all types of contaminants. As a result, membrane switches are preferred for humid and otherwise harsh environments.
#3) Supports Backlighting
Membrane switches support backlighting as well. Available backlighting solutions include electroluminescent (EL) and light-emitting diode (LED). EL costs less than LED. Price aside, many businesses still prefer LED-backlit membrane switches because of their long-lasting properties. Since they consume less energy — as well as produce less heat — LED backlighting generally lasts several times longer than EL backlighting.
#4) 4 Layers
A typical membrane switch is constructed of four unique layers, each of which play an important role in its function. There’s a top graphic layer, followed by an electrical contact layer, then a spacer layer, and another electrical contact layer. Pressing the switch’s button forces the two contact layers to meet, thereby completing the electrical circuit.
#5) Tactile Feedback
Membrane switches are capable of producing tactile feedback. Also known as haptics feedback, tactile feedback is the physical force that you feel when you press the switch’s button. It’s designed to reduce input errors, as well as improve user experience. When you feel the tactile feedback produced by a membrane switch, you’ll know that it registered your key press. Without tactile feedback, you may inadvertently press the same button two or more times.
