On 6/8/05, James Newton, Host <jamesnewton@piclist.com> wrote:
> 
> I've never seen it done, so there is probably a good reason, but why not add
> a capacitor to each LED as a means of expanding the time it is on and
> allowing more current to be pumped in to it without exceeding the rating of
> the LED itself?
> 

For these "scanned" displays all of the push lines are connected to
all of the displays at the same time and the common sink is scanned
across them. If any of the shared lines had a capacitor it would
"bleed" into the other displays when the common was being scanned
across the displays.

An additional diode for each of the segments before the capacitor
would fix it, but would be a lot of extra parts.

If you push the momentary current up a little bit, you don't lose much
brightness at all.

- Ben

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