I am putting together a house lighting project using RGB's, my plan is to use a TLC5940 driving 5 RGB LEDS (15 PWM's), and multiplexing 8 LED's onto each channel, giving 40 total RGB LED's with this setup. I would like anyone with much better expertise then my own as to if the circuit I designed is adequate enough. I did breadboard the design with 4 multiplexed LED's per channel and it seemed to run fine (though I will probably have to use dot correction for best results...). Note that the schematic is not complete, I did not bother at this point to fully schematic out the 595 and 5940's power, ground, and arduino connections, but the schematic for the LED's is there. I am biasing the 5940 for 40ma per channel considering how fast the multiplexing is happening to get a good brightness (I could go to 60ma but I will be taxing my available power supplies doing so).
I am not sure either about the best placement of capacitors for power smoothing, as I noticed with the scope that the multiplexing power or PWM is not as clean as it should be, so any ideas on that would be great too, thanks!
Schematic:
http://www.digikey.com/schemeit/project/a4g/LED-Project
I am not sure either about the best placement of capacitors for power smoothing, as I noticed with the scope that the multiplexing power or PWM is not as clean as it should be, so any ideas on that would be great too, thanks!
Schematic:
http://www.digikey.com/schemeit/project/a4g/LED-Project
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