Thus spake Steve Hardy (hardy@SWENG.STORTEK.COM):

> time).  Why?  Well, for a particular brightness of the overall display,
> the average current for each LED must be the same.  If row-by-row

Not true. The perceived brightness is related more to peak brightness
than average - i.e. for the same average current the LED will appear
brighter with a low duty cycle (and therefore high peak current)
than with a high duty cycle. Driver considerations are another matter,
but for maximum brightness you should aim to drive the LED at its
rated peak current, and adjust the duty cycle so as not to exceed the
rated average current.

--
Clyde Smith-Stubbs    | HI-TECH Software,       | Voice: +61 7 3354 2411
clyde@htsoft.com      | P.O. Box 103, Alderley, | Fax:   +61 7 3354 2422
http://www.htsoft.com | QLD, 4051, AUSTRALIA.   |
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