> >1)  Silicon diodes typically drop 0.6 - 0.7V.
> >2)  A standard (red, green, or amber T-1 or
> >     T-1 3/4) LED will drop around 1.8 - 2.1V.
> >3)  White and blue LEDs are along the lines of
> >     4 - 5V.
>
> Oops. In that case, taking 2.0V for the forward drop, the series
> case would require a 700-ohm resistor which would dissipate
> 420mW of heat. In the parallel case, one common resistor for
> all 5 LEDs would dissipate 2200mW.

There's still something wrong with you series case.  5 LEDs at 2v each drop
10V.  This leaves 14V for the resistor.  14V * 20mA = 280mW.  I can't see
where you got the 420mW from.


********************************************************************
Olin Lathrop, embedded systems consultant in Littleton Massachusetts
(978) 742-9014, olin@embedinc.com, http://www.embedinc.com

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