This circuit is from old European documentation. R1 depends on the output voltage of the microcontroller. We can use 270 or 330 ohms for 5 V outputs. The relay is 50 mA or 100 mA depending on the voltage in this sector is 5, 6 or 12 V.
This circuit is from old European documentation. R1 depends on the output voltage of the microcontroller. We can use 270 or 330 ohms for 5 V outputs. The relay is 50 mA or 100 mA depending on the voltage in this sector is 5, 6 or 12 V.