Re: 12 LED resistance circuit help


"John Bokma" wrote:

<snipped exactly what I was going to post>

> Note that I did this calculation, later checked it with a voltage
meter,
> and yet already 2 exotic LEDs died on me. I think it's a bad badge.
> (Unless someone can point out my errors).

I came up with the same calculation as you. If LEDs are dieing, then
20mA may be a bit too much current. Since there are two LEDs in series,
one may hog more current than the other resulting in its demise. You
might consider not driving them so hard. There is probably a relatively
insignificant brightness difference between 10mA and 20mA anyway.

.

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