How to Choose the Right Relay

Relays come in a variety of form factors, styles, and technologies. Depending on your application, only one relay type may be suitable. In other cases multiple relay types may be appropriate. By understanding the strengths and weaknesses of the different relays you should be able to pick the one that is best suited for the job at hand.

Note: Although many of the conclusions in this document apply to all relay applications, it discusses specifically what factors to consider when looking at the different types of relays that are used on switch modules targeted at automated test equipment (ATE) applications. The comparisons made here are between relays with similar voltage, current, and power ratings in the form factors that are found in typical switch modules.

The most common types of relays used in ATE applications are:

• Electromechanical Relays
• Reed Relays
  
• Solid State Relays (SSRs)
  
• FET Switches