Wiring RGB LED’s
So I’ve been looking into this a little more. I took your guys idea of using the
TLC5940 LED Driver.
So now I’m asking for some help again. I figured 1 long question that eventually solves this is better then a bunch scattered throughout stackexchange. Now comes the wiring part. I’m using an arduino wiring tutorial as a start since I’m in way over my head. I’m also referring to the data sheet. According to the diagram pin
27 or VPRG confuses me. The Arduino diagram has it grounded so I am grounding. . . How do I connect this correctly to the pi? I’m also guessing I need resistors too…
I’m sorry if this sounds really stupid, but I am a true beginner at this stuff. You have to learn to crawl before you can walk.
Update 2 – after comment
Taking into account some of the answers and comments this would be the wiring diagram then? 330ohm to anode. 2k ohm to pin
20. How does the inputs get from the pi to chip?
Would you clarify a few things? Do you want to drive all red, green and blue LEDs of 8 RGB LEDs (that will take 24 outputs, so 8 more than the 16 provided by a TLC5940). What RGB LEDs are you using? We need to know if they are common anode or common cathode (your wiring looks like common cathode, which won’t work with a TLC5940, which can only sink current. Common cathode will need a different chip). Also blue might not switch on using 3.3V, so will need 5V. Must it be through hole electronics (e.g DIP), and not surface mount. Do you care if it uses 3 chips instead of one? – gbulmer Nov 8 ’12 at 0:37
@gbulmer Sorry about that. I don’t have the package the LED’s came in, but think you are correct on Common Cathode as to light them in arduino I wrote a HIGH. I will pick up some Common Anode from radioshack tonight. I Have 5 TLC5940 chips and don’t care if I use them all. The reason why I’m going with DIP is to use a breadboard (baby steps). After I get it working I’ll switch to surface mount.
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