Switches are commonly used to control devices. A switch, of course, is an electrical component that can complete or break a circuit. While all switches are essentially controllable circuits, they are available in different types. In addition to mechanical switches, there are capacitive switches. Below is a list of frequently asked questions about capacitive switches.
How Do Capacitive Switches Work?
Capacitive switches work by measuring changes in capacitance. They emit an electrical charge across the top layer. Touching the top layer with a conductive object, such as a bare finger, will result in a change of capacitance. The capacitive switch will then respond by completing or breaking the circuit.
What Parts Are Capacitive Made Of?
Most capacitive switches are made of a few basic parts. They feature a top layer, which is the graphic overlay layer. Below the top layer is a circuit layer. And at the bottom is a backer layer.
What Are Capacitive Switches Used For?
Even if you’re unfamiliar with how they work, you’ve probably seen or even used a capacitive switch in the past. Remote controls, for example, often feature capacitive switches. Remote controls for TVs, stereo systems, lighting systems and appliances may feature multiple capacitive switches. You can also find capacitive switches in airplane flight control systems, laboratory equipment, medical devices, keyboards and more.
Are Capacitive Switches Long-Lasting?
Capacitive switches are absolutely long-lasting. Like other touch switches, they don’t contain any moving parts. Mechanical switches have moving parts. Each time you press a mechanical switch, you’ll engage its moving parts. Over time, mechanical switches can fail due to the constant movement of their parts. Capacitive switches are touch switches, so they don’t contain any moving parts.
What Type of Circuit Do Capacitive Switches Use?
A circuit is an essential part of a capacitive switch. As previously mentioned, capacitive switches are made of a graphic overlay layer, a backer layer and a circuit layer. The circuit may consist of a Printed Circuit Board (PCB) or a Flexible Printed Circuit (FPC). The former is rigid, whereas the latter is flexible.
Do Capacitive Switches Feature Backlighting?
Backlighting is optional with capacitive switches. You can choose capacitive switches either with or without backlighting. Some of them feature light-emitting diode (LED) backlighting. Other capacitive switches feature electroluminescent (EL) backlighting. Light guides can be used with backlighting as well. Light guides don’t produce light. Rather, they are designed to distribute or “guide” the light. Using light guides with backlighting will create a more consistent level of brightness.