Using the 4N35 to drive a high power LED


This is my first post in the forum.
Recently I got an Arduino starter kit and I would like to use the Arduino to drive a high power LED.

May I use the 4N35 included in the kit for the purpose?

The LED is 0.5W, 3.0V-3.2V, 150mA and will be powered from a 4S lipo on a quad. Actually it will emulate the strobe aviation lights of an aircraft.

I've built a prototype using a normal LED.
Pin 13 of the UNO is driving the optical side of the 4N35, and I have the LED's anode connected to pin 4, anode of the lipo connected to pin 5 and the cathode of the LED connected to ground using a 220Ohm resistor.

I've been reading the manual of the 4N35, but I can not understand if the 150mA of the high power LED are within it's limits. Any advice welcome!

Thank you in advance,


Short answer. No.

From the datasheet:

Collector currentt IC 100 mA

And that means at 100mA you will break the 4N35... At 150mA... it will go poof pretty fast.

You will need an additional part as a driver... though this does make me wonder why you want to use the 4N35 at all.

Thanks for the prompt reply pwillard.

The idea is to use some kind of relay to drive the LED. The 4N35 was the closest thing available in the kit.

This one seems to be able to handle it, if I read the data sheet correctly, right?

If you may provide an alternative, keeping in mind that space and weight are a premium on a quad, please do so.



By driver do you mean something like this?

That should work.