LED brightness, how to - Electronic Circuits Projects Diagrams Free

Mac-ca · 10th June 2008, 10:44 AM

heyo,

I'm looking for a way to control the brightness of led's without using a rotary switch

i've only got 5 led's so power restrictions shouldnt be to much of an issue..

I want to control the brightness from dim (near off) to fully bright

Gayan Soyza · 10th June 2008, 10:51 AM

This will full fill your requirement.

ColorFade

Mike, K8LH · 10th June 2008, 10:16 PM

How would you like to control them? Using five pots'? A selector switch and a single pot'? Five sets of <up> <down> push button switches?

Mike

Henry T · 10th June 2008, 10:34 PM

This can be done with 2 OpAmps a few resistor a capacitor (and a switching transistor for bigger powers)

The first OpAmp is a sawtooth generator and the second is just a comparator with an adjustable trigger level. This can be done with a potentiometer or what ever you want to use for variable voltage control.

I have an eagle schematic here somewhere for a RGB-controller that works that way, if you want it, I can upload it...

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10th June 2008, 10:44 AM	(permalink)
Mac-ca	LED brightness, how to heyo, I'm looking for a way to control the brightness of led's without using a rotary switch i've only got 5 led's so power restrictions shouldnt be to much of an issue.. I want to control the brightness from dim (near off) to fully bright __________________ V=IR Period.

10th June 2008, 10:51 AM	(permalink)
Gayan Soyza	This will full fill your requirement. ColorFade __________________ Gayan My Website http://gsmicro.blogspot.com/

10th June 2008, 10:16 PM	(permalink)
Mike, K8LH	How would you like to control them? Using five pots'? A selector switch and a single pot'? Five sets of <up> <down> push button switches? Mike

10th June 2008, 10:34 PM	(permalink)
Henry T	This can be done with 2 OpAmps a few resistor a capacitor (and a switching transistor for bigger powers) The first OpAmp is a sawtooth generator and the second is just a comparator with an adjustable trigger level. This can be done with a potentiometer or what ever you want to use for variable voltage control. I have an eagle schematic here somewhere for a RGB-controller that works that way, if you want it, I can upload it... __________________ There are no stupid questions, but PLEASE, think twice before asking them Last edited by Henry T; 10th June 2008 at 10:37 PM. Reason: voltage control variable