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Insight - How Tactile Switch works

Written By: 

Arpit Jain
Tactile Switches are most often found in control panels of monitors, televisions, mobiles, radios, etc. They are widely used in industry for different purposes. They come with various number of pins as per the requirement. A tactile switch has only two states ON and OFF. Here 4 pin tactile switch is discussed.
4-Pin Tactile Switch
Fig. 1: 4-Pin Tactile Switch

Outer Metal Covering

The switch is kept closed by using a metal covering as shown below.
Image of Metal Cover
Fig. 2: Image of Metal Cover
Metal Cover
Fig. 3: Metal Cover


Inside the switch we can see there is a hat like thing. Actually it’s the button that we tap. The button looks very similar to a hat. At the bottom of the button there is a pointing arrow. The use of the arrow is discussed later.
Hat-Shaped Button of Tactile Switch
Fig. 4: Hat-Shaped Button of Tactile Switch

Conducting Plate

Below the button there is a conducting plate. This plate isn’t flat but a little bulged. The image of the plate is shown below.
Image of Conducting Plate
Fig. 5: Image of Conducting Plate
Image Showing the Bulge of Conducting Plate
Fig. 6: Image Showing the Bulge of Conducting Plate

Bottom View

Below the plate we have the pins that we use to connect.
The Four Pins Placed Below Conducting Plate
Fig. 7: The Four Pins Placed Below Conducting Plate
Interior View of Pins
Fig. 8: Interior View of Pins
When the button is tap the arrow like structure in the button pushes down the bulged plate. When this bulged plate comes in contact with the pins conduction begins and the switch is said to be in ON state.


Please tell which leg makes contact with which leg so that it can be used


First you check which which pair of legs are short circuited. Then use one pair of legs as one terminal and another pair of legs as another terminal.


Hope you can now make your own connections

if we short two terminals of that then is it works ?


if 2 legs are cut off will it work like a 2 pin switch

Is this like a pen, where a click makes the plate stay in contact with the metal legs until clicked again, or does it turn off (cut contact) everytime you release it?