🚀 go-pugleaf

tom@syssoft.com (Rodentia) writes:
> Anyone making a tricolor LED yet?

fng@questor.wimsey.bc.ca (Felix Ng) replies:
> I think Radio Shack sells one.  Red and green with DC and yellow with AC.

	I think Rodentia (presumably not tom@syssoft.com's real name) meant
an LED with all three primaries, i.e. red, blue, and green that you could
mix anyway that you like.  The red/green/yellow LEDs are just a red and a
green LED back-to-back.  One polarity lights one, the other polarity lights
the other, and AC lights them both, a half-cycle each.

	I could see packaging all three in one plastic case, but I don't
see how you make it work with only 2 pins.  The minimum pin count I could
see is 3, with the 3 LEDs delta connected, allowing you to light any one or
two at a time.  If you wanted to light all three at once, you would need 4
pins; an anode for each and common cathodes (or the other way around, if
you prefer).  It would certainly be a heck of a lot simplier that getting
the odd bipolar voltages you'd need in the delta connection.

tom@syssoft.com (Rodentia) again:
> how would power consumpion compare to LCD shutter solutions?

	My latest Digi-Key catalog shows most of the LEDs drawing 70-90 mW.
Even for a modest resolution 512 x 512 display at 70mW/pixel, you'd be
drawing 18 kW!  Hardly low power.
--
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