RGB LED on Zilog ZNEO Z16F Dev Board

I wanted to try out a tri-colour LED I bought online on Sparkfun Electronics, and try out my dev board... The Z16F board is hooked into an RGB LED through three PWM channels, and three potentiometers through three ADC channels. You can also flip the switch on the board to output a sine wave of slightly different frequency to each of the RGB channels. You can mix the RGB amounts to make pretty much any colour you want, although it looks best if you diffuse the colours through a piece of paper or something

Category:

Science & Technology

Tags:

• zilog
• z16f
• LED
• SparkFun

[prankmypants]

excuse my ignorance im i to understand that this is 3 leds in 1 with a common ground and i could simply plug the shared ground to -5v then take 3 variacs from +5v to each of the led terminals to control the brightness?

[precosky]

@prankmypants Yep, the three LEDs are in one plastic lens with a common ground, so it has 4 pins in total. The voltage/current characteristic of LEDs is very nonlinear, and so variacs would sort of work, but not that great. For brightness control, Pulse Width Modulation is the best way to go with LEDs, or you can also use a variable current source. A variable voltage source or variac won't work so well.

[prankmypants]

@precosky

wow thanks for speedy response. yeah really all im looking to do is replace all the LEDs in my computer fans and have a colour switch and possibly a colour pulse mode depending on how hard this is. what would you recommend?

[precosky]

@prankmypants Cool, that'd look pretty neat. The ultimate solution would be a microcontroller with PWM outputs, but you could probably get started quicker using an LM317 and a potentiometer as a variable current source

[microchoc]

SPARKFUN IS AWESOME

[prankmypants]

@precosky

thanks again, i looked up the LM317 and feel confused. do you possibly have a link to picture or something that shows the circuit you had in mind so I may understand what im doing better?

[HolgerHartenstein]

GOOD CONTROLLER Z16F

[AustinSalgat]

Very nice!

[hiatuszero]

nice