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Using Arduino => LEDs and Multiplexing => Topic started by: dmillsap06 on Oct 13, 2018, 06:33 am

Title: Two LEDs, Same Pin, which resistor?
Post by: dmillsap06 on Oct 13, 2018, 06:33 am
Newb alert!

I have two white 3mm LEDs that I'm wanting to control off of one pin.  Is this okay to do?  I'm using one resistor currently before the LEDs as well as seen in screenshot provided. 

What size of resistor should I be using or should I be using two?  Look forward to your comments. 

Thanks.

Title: Re: Two LEDs, Same Pin, which resistor?
Post by: Grumpy_Mike on Oct 13, 2018, 09:56 am
Quote
I'm using one resistor currently before the LEDs
Then don't. They will not shairing current equally and will eventually get unequal brightness.

Keep the resistor high because white LEDs don't need much current to be too bright to look at. I have used 1K resistors on white LEDs in the past. It depends on how bright they need to be.

Remember the total current out of a pin should be less than 30mA.