Yes, I agree. It should be labeled 3R9.Additionally - do you know that you cannot light all three at the same time? If you try, the one with the lowest VF will light and the rest will not or will be dim.And red will be the lowest voltage drop.I would also drive those transistors a little harder. 4.3mA IBE for 320mA of ICE is not pushing it very hard into saturation. A little variation in Beta could cause one or more transistor to dissipate a bit more power, and there isn't much room for that in those tiny transistors. In fact, that requires a Beta of 75, but the minimum rated beta for that transistor at 300mA is only 60.As for measuring the current in operation, connect a 0.1 or 0.01 ohm resistor in series and measure the voltage drop. If you want to see it operate without an LED, at 320mA a 10 ohm resistor will drop 3.2V, about what the LEDs will drop. So stick a 10 ohm 2W or better resistor in there and measure the voltage.You did use a resistor when connecting to your 3.3V source, right? If not, you might fry the LED.Of course the output is high with no load connected. It is regulating the current, and with no current draw, the voltage reaches the maximum it is capable of supplying.
logic in the code should be the same..no? both common anode leds? I am using internal pull-up resistors on those pins.
3.) I think your saying that the 1k resistor value between the transistor and Arduino pin is too high? lor is so I get more/full saturate of the gate, allowing the led to get full (constant) current? suggested value to use?
Im not following on how to measure the current.. (sorry).. and I dont have any LARGE resistors like that around (no 1-2 watt fattys) just regular old SMD and through hole resistors.. of 1/8, 1/4, 1/2 watt..etc..
4.) Use a resistor when? you mean when 'testing' the LED on my PSU? I just cranked the voltage down to +3.3v.. and did a quick TAP on the leads.. to ensure it was working/is bright..no resistor.. (I dont recall if I dialed down the AMPs or not? usually it at 1A or so)
Im measuring roughly +6.72v on the OUTPUT (I removed the RGB LED and metered the plug/wires ends to get this)sounds ok with voltage drop across the whole board/components? (but makes me worries since thats WAY over the vF of the RGB led I'm using)
I dont understand this:"Of course the output is high with no load connected. It is regulating the current, and with no current draw, the voltage reaches the maximum it is capable of supplying."this is my first time using the LM317 chip..and trying to make a constant current circuit ever. (working my way through it)
Use a resistor when? you mean when 'testing' the LED on my PSU? I just cranked the voltage down to +3.3v.. and did a quick TAP on the leads.. to ensure it was working/is bright..
I have used red LEDs with MegOhm+ series current limiters as pilot lights in 110Vac circuits (more for continuity checking than pilots, but you get the picture. Voltage isn't really the issue.