From: "Nucharin W. Jansen"
Subject: Re: Best way to power array of LEDs?
Date: Fri, 08 Nov 2002 04:15:42 +0700
Organization: C.S. Communications Co. Ltd.
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NNTP-Posting-Date: Thu, 7 Nov 2002 21:16:08 +0000 (UTC)
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oh! I see. Thank you very much.
That why he parallel at 3.1v instead of 3.6v
Lizard Blizzard wrote:
> > http://www.ResurgentSoftware.com/Perfect_LED_Light.html
> > He parallels all LEDs together without any resistor to
> > constant voltage regulator.
> If you read the rest of it, he says that the LEDs are all run at
> substantially below their maximum current to get better efficiency.
> Something like 8 mA, in one of his designs. So if you have one LED that
> has substantially lower Vf, and it decides to hog twice the current,
> then it's still only 16 mA, which is well below the maximum, so no big
> deal. But putting LEDs in parallel without Vf matching and running them
> at or near maximum is just an invitation for self-destruction.
> > At last week, I thought the same as him but I plan to do with
> > MAX757 ( DIP300 ) stepup IC from batt only 1 or 2 cells.
> > But after read several articles here, I get confuse so much.