Basics of Switches

Recently I wrote an article about switches. Before working at DigiKey I had never really thought twice about them. I knew what they did, but that was about it. But over the course of the last year I have spoken with many customers about switches. Some of the calls have been about replacing a switch, while other calls have been about picking a switch to use in a new design. I have learned many things about switches in the process and wanted to take a chance to share some of what I have learned.

NKK Switches' Miniature Toggle Switch

In the article “Switch Tutorial” several concepts were covered. Hopefully the article will shed some light on the intricacies of switches while helping you locate these switches and their accessories. Some of the topics that are covered in the article are:

Circuit

• Difference between poles and throws
• Different types of circuits
  • SPST
  • SPDT
  • DPDT
  • Several others

Electrical Considerations

• Maximum ratings
  • Voltage
  • Current
• Why there are multiple ratings for the same switch

Types of switches

• Pushbutton Switch
• Tactile Switch
• Dipswitch
• Rocker Switch
• Snap Action Limit Switch
• Toggle Switch
• Rotary Switch
• Keylock Switch

Accessories

• What kinds of accessories are typically available
• Where to find these accessories on the DigiKey website