Re: LED control circuit

From: bob (sorry_at_spamboys.com)
Date: 11/04/04 

Date: Thu, 4 Nov 2004 21:24:52 -0000

"> 4x5...or 20 all together.

yep

> How much overlap? In other words, only *after* the first bank reaches full
> intensity does the next one start to 'show?' Or sometime beforehand? How much
> overlap? Does it need to be adjustable?

No overlap at all, no need to adjust

> Gradual intensity increase, then. Either controlling current or PWM, I guess.

> Yes, that affects the voltage requirements and.. possibly, the current. Are
> these like those Luxeon multi-watt things? Or just simple white, non-descript
> LEDs (radio shack style)?

Non descript, simple "white" LEDs

>
> In pure analog hardware, I believe this would either require some remarkable
> ingenuity and creative insight to make it simple (if possible); or else it may
> be done with a micro using PWM for intensity control.

Hmmmm, thats a bit beyond my me , how about a five postion rotary switch
and some kind of delay/ramp/decay etc arrangement so the LEDs take about one
second to reach full brightness and one second to extinguish when switched off ?
is that analogally possible?

Thanks again
BoB

>
> Jon

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