Hey lefty that is a nice looking board. Look forward to hearing how it performs. Limiting the current that is fed into the arduino is one way to limit its magic smoke potential?
Yea it's cute alright. It still brings up that argument about what constant current really means and what is a CC/CV supply. I have stated (correctly I might add
) that a supply like this should not be called a constant voltage/constant current supply but rather a constant voltage supply with an adjustable current limit where it will gracefully decrease (foldback) the output voltage to maintain the adjusted current amount if faced with a decreasing load resistance. Example is if you set this to 10 volts output and 1 amp current limit and then wire a short to the output terminals you will still get a steady 1 amp current flow, but most certainly won't see 10vdc applied across the wire!
Alternately if you remove the wire and replace it with a 20 ohm resistor you will not then get a constant 1 amp of current flow but rather only 500 ma, so nothing constant current about that, just automatic current limiting action when the load resistance forces it into that mode.
Now that is not to say you can't operate it as a constant current supply for say a 350ma power led, you just set the current limit to 350 ma and set the output voltage well above the Vf value of the led and the power supply will stay in it's current limiting mode forever and will raise and lower the output voltage to any changing load condition of the LED.
So I guess you can say it can operate as a constant voltage supply or as a constant current supply, but just not at the same time, ohms law still wins.