3mm LEDs are handy to have in your go to drawer for those times when you need something a bit smaller.
Included in this 50 pack are:
I don’t have a maximum recommended current, but I would shoot for about 20 mA maximum (most LEDs are happy around that).
Remember to use a current limiting resistor, no resistor = instantly destroyed LED in most cases.
A customer asks "what resistor do I need for a 12v supply". Here is a rough ballpark formula for you for 1 or more led's in series which will get you around 20mA through them (give or take!)
Vf1 = (R+G+Y)*2.1
Vf2 = (B+W)*3.1
Vr = 12 - Vf1 - Vf2
Resistance = Vr / 0.02
where R G Y B and W are the number of each LED you are putting in series.
Note that if Vr is negative, you have too many led's in series :)
Example 2 Red, 1 Green and 1 Blue in series:
Vf1 = (2+1+0) * 2.1 = 6.3
Vf2 = (1+0) * 3.1 = 3.1
Vr = 12 - Vf1 - Vf2 = 12 - 6.3 - 3.1 = 2.6
Resistance = 2.6 / 0.02 = 130
