Roman,

What happens when they age out over, say, 5 or 10 years?

I might do as you suggest for a personal project -- well maybe
*consider it* at least ;) I don't think I'd ever parallel LED's
in a commercial application though. It just isn't worth the risk
for a couple pennies worth of parts that are guaranteed to work
over the long haul.

Just my perspective on things...

Matt Pobursky
Maximum Performance Systems

On Thu, 11 Jul 2002 19:07:37 +1000, Roman Black wrote:
>Wow, that's three against, here goes the one for:
>I do use leds in parallel and it has always worked
>well for me. :o)
>Sure, when they are junkbox leds you will get large
>tolerances in Vf, especially with older leds. And of
>course the difference between colours.
>
>BUT, with new leds of the SAME type, like from a bag
>of 100 straight from the manufacturer (not from a
>shop's parts drawer), you can parallel them with no
>problems. The "knee" of the Vf curve is quite soft
>and they will share current well, within about 5%.
>So the leds in parallel will be from about 19mA to
>21mA. Generally you won't notice any difference in
>brightness.
>-Roman

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