What is the best way to power 16 super bright LEDs using an Arduino Uno to achieve max brightness?
Each LED has the following characteristsics:
IF Typical (mA) = 20 VF Typical (V) = 3.2 IV Typical (mcd) = 3700 IF Max Continuous (mA) = 30 Preferred Series Resistor (ohms) 5VDC = 91 9VDC = 300 12VDC = 430
Output from Arduino pins = 5V.
Power suppply is 12V, while the final will be an Automotive ~12V rail.
I've used two LED calculators:
http://led.linear1.org/led.wiz this site says I should use 16 LEDs in parallel with 100Ohm resistor on each one.
http://www.hebeiltd.com.cn/?p=zz.led.resistor.calculator this site says I should use 16 LEDs in parallel with just one 5.625Ohm resistor.
The Arduino Uno has 14 digital pins outputting 5V. I would like to use the least amount of 5V digital outputs, and the least amount of resistors necessary, while maintaining maximum brightness.
Hope you can help :)