Varying the voltage will work but it's touchy and not transferrable to
other LEDs.  Best way I've seen is simple PWM duty-cycle changing.

nick@veys.com / www.veys.com

> -----Original Message-----
> From: pic microcontroller discussion list
> [mailto:PICLIST@MITVMA.MIT.EDU] On Behalf Of Micro Eng
> Sent: Wednesday, January 15, 2003 8:26 AM
> To: PICLIST@MITVMA.MIT.EDU
> Subject: [EE]: varying the intestity of an LED
>
>
> Just pondering this on my way to work...after being annoyed
> by some of the new LED based taillights
>
> If you want to vary the brightness of an LED, would it be
> better to vary the voltage, say a PWM circuit driving a
> voltage-follower transitor, or adjust the circuit voltage (ie
> the resistor using a digital pot) ?
>
> _________________________________________________________________
> MSN 8 with e-mail virus protection service: 2 months FREE*
http://join.msn.com/?page=features/virus

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us! email
listserv@mitvma.mit.edu with SET PICList DIGEST in the body

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email listserv@mitvma.mit.edu with SET PICList DIGEST in the body