Star Field

Brian D.

Hi Everyone! Brian here, creator of the BS2 Jukebox (cust. applications)

Need a little guidance - I want to create a programmable starfield for above the bar in the basement using actual LED's. I want to fade the LED's in and out (not just on/off) and use maybe 38 individual outputs of a BS2-40 (in bundles of about 15 LED's per output).

My question is, what do you guys think would be a good circuit to build for the output, pulse width modulation, or other? I have never done anything with PWM and LED's and not sure how to construct a circuit. Probably using a TIP3055 power transistor for each output but how to vary the output from dim to bright?

Thanks !

Brian Dalziel

briandalziel.com

Irone

How Ya Doin'? Check out Column #126 from Oct. 2005 in the programs for Nuts and Volts. You can find them under resources at the Home Page of Parallax. He uses a 220 uF capacitor and the ULN2003 Darlington Transistor IC's. He used the BS1 so you will have to change the program.

Casey

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I fish, therefore I lie!

Frohman

WHOH WHOH hold everything! he doesn't need the EXTRA THINGS THAT COST MONEY!

Take a look at how this guy made an old analog voltmeter display the AQI (Air Quality Index):
blog.makezine.com/archive/2008/11/net_data_meter.html

He used Pulse Width Modulation; this can make LEDs seem to dim even though they aren't.

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MAGGOTS!

hover1

Your replies in all the forums have been pretty rude. Lighten up!

The Original Poster needs to run 15 LED's off of one pin of the Stamp. That is going to require some extra circuity to drive it.

You might do a little homework on the project before you post.

Frohman said...
WHOH WHOH hold everything! he doesn't need the EXTRA THINGS THAT COST MONEY!

Take a look at how this guy made an old analog voltmeter display the AQI (Air Quality Index):
blog.makezine.com/archive/2008/11/net_data_meter.html

He used Pulse Width Modulation; this can make LEDs seem to dim even though they aren't.