John Larkin wrote:
On Sat, 28 Jan 2012 21:32:15 +0100, "petrus bitbyter"
wrote:

"John Fields" schreef in bericht
news
On Sat, 28 Jan 2012 12:39:20 -0600, John Fields
wrote:

These curves are for a white LED with nominal and maximum forward
currents of 20 and 30mA, respectively.
---
"Connect-the-dots" works wonders. :-)

--
JF



Well, it tells what you and I - and several others - knew and told already.
If one realizes that this curves are typical values that may vary even for
LEDs from the same batch and also depend on temperature he'd have to agree
that constant voltage to drive a LED is bad engineering practice.

petrus bitbyter



"Bad engineering practice" is an interesting term. I think it means "I
don't approve of that."


Howsomever, the "constant voltage" scheme is eXtremely (yes, "X"
rated) common way to drive parallel LEDs..three 1.5V cells in series
driving a number of LEDs in parallel (have a light with 24 LEDs driven
that way, NO resistor).