> Hi all. I'm looking to do some PWM on some high power LEDs. PICwise,
> everything is working great. Now comes to the EE part, where I have much
> less skill. I have to power 5 LEDs with a current of about 20mA each.
> It's easier for me to provide higher current rather than higher voltage,
> so I was thinking about paralleling them. But, I'd like to only have one
> current limiting resistor for the string of 5.

Bad idea.  Random part variations will cause one LED to start out drawing
more current.  That alone would put it over spec, but it gets worse.  The
LED drawing more current gets warmer than the others, causing it to draw
even more current at the same voltage causing it to get even warmer...


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