Switch Basics


Contributors: Jimb0


One of the most elementary and easy-to-overlook circuit component is the switch.


Switches don’t require any fancy equations to evaluate. All they do is select between an open circuit and a short circuit. Simple. But how could we live without buttons and switches!? What good is a blinky circuit with no user input? Or a deadly robot with no kill switch? What would our world be without with big red buttons you should never, ever press.

Covered in This Tutorial

  • Momentary vs. Maintained Switches
  • What do SPST, SPDT, DPDT, etc. all mean?
  • The difference between normally closed and normally open buttons
  • Lots of pretty button pictures
  • Important switch ratings
  • Switch applications

Suggested Reading

Before diving into this tutorial, make sure you’re up to snuff on the most basic of electronics knowledge. If you’re not familiar with the following concepts, consider reading their tutorials first. Then come back, and we’ll have some fun button talk.

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