choosing-components-for-the-relay-module

Find the following types of components

• Relay
• Transistor (NPN)
• Opto isolator
• LED
• Kickback diode

Recall the following design goals:

• Swappable components with easy to solder packages.
• Low cost.
• Relay can handle up to 250V AC (though we suggest using it at 24V DC)
• NPN can easily handle/switch coil current.
• Surface mount opto isolator