Switches are commonly used to control electrical devices. They feature one or more buttons that, when pressed, open or close a circuit. While some switches use a mechanical method of operation, though, others are touch based. Known as touch switches, they open and close circuits just like their mechanical counterparts. Mechanical switches, though contain moving parts, whereas touch switches do not.
What Is a Resistive Switch?
A resistive switch is a type of touch switch. if you’re familiar with touchscreen technology, you may recall hearing or reading about “resistive” touchscreens. They are the second-most popular type of touchscreens on the market, surpassed only by capacitive.
Both resistive touchscreens and resistive switches use a similar nonmechanical method of operation. When you press your finger against one of these resistive devices, it will identify your command. Resistive touchscreens will respond by changing the display, and resistive switches will respond by opening or closing the circuit.
How Resistive Switches Work
Resistive switches work by leveraging multiple layers of an electrically resistive material. They typically feature a top layer and a bottom layer. By default, these two layers are separated. Both layers also feature patterned electrodes facing each other. An electrical charge is then applied to the bottom layer.
When you touch a resistive switch, you’ll press the top layer into the bottom layer. Only the bottom layer will have a constant electrical charge. Touching the resistive switch, though, will allow the electrical charge to travel from the bottom layer to the top layer, as both layers feature patterned electrodes facing each other.
Keep in mind that resistive switches aren’t the same as capacitive switches. Capacitive switches are also classified as touch switches, but they work by measuring changes in capacitance. Capacitive switches will apply a uniform electrostatic charge to the top layer. When a conductive object, such as a bare finger, touches this top layer, the capacitance will change. The capacitive switch will then open or close the circuit. Resistive switches don’t measure changes in capacitance.
Resistive vs Mechanical Switches
1There are mechanical switches available as well. Mechanical switches, of course, don’t use a touch-based method of operation. You’ll still have to touch them to control them, but mechanical switches feature a different design than touch switches like resistive switches.
Mechanical switches use a traditional, mechanical method of operation. They have moving parts that engage a circuit. Resistive switches are touch switches that use multiple layers to engage a circuit.