Flyback Diode Direction: Build a Protected 5 V Relay Driver
Wire a flyback diode correctly across a 5 V relay coil. Follow the switch-off current path and calculate a transistor driver for a small relay.
Unravel the Mystery of Electronics

Soldering required. Check the supplied parts and board revision.

Listing specifies 5-volt direct current. Soldering required; battery and glue not included.

Breadboard, wires and assorted parts. Arduino controller board not included.

Surface-mount soldering practice. Battery and battery holder not included.

Clock-and-case project kit. Soldering required; check included parts and power requirements.

Soldering and assembly required. Check battery and track requirements before buying.
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Wire a flyback diode correctly across a 5 V relay coil. Follow the switch-off current path and calculate a transistor driver for a small relay.
In electronics, “component biasing” or “support circuits” refers to the external components required for proper operation of a main component (e.g., microcontrollers, transistors, voltage regulators, …
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Supplier product photo
Soldering required. Check the supplied parts and board revision.

Supplier product photo
Listing specifies 5-volt direct current. Soldering required; battery and glue not included.

Supplier product photo
Breadboard, wires and assorted parts. Arduino controller board not included.

Supplier product photo
Surface-mount soldering practice. Battery and battery holder not included.

Supplier product photo
Clock-and-case project kit. Soldering required; check included parts and power requirements.

Supplier product photo
Soldering and assembly required. Check battery and track requirements before buying.