I have an off-brand (RedQualis) Arduino Uno that I am using to power one string of 50 addressable LED's using Fast_LED. I am using the 5v pin + Gnd for the lights and digital pin 6 for the I/O. To be safe, I encased this board in a small enclosure to run this string of lights for a Christmas decoration. However, I noticed that the enclosure is getting a little bit warm. Not super hot, but a little warm. I suppose this is because I am driving the LED's directly from the Arduino.
My question is this: I have a temperature/humidity sensor for the Arduino. I was going to use this in combination with an if(statement) to allow the LED's to come on only if the temperature remains below a certain value. However, this sensor needs its own 5v supply, which I've used for the LED's.
Can I use digitalWrite(7, High) as a 5 volt supply on pin-7 for this sensor? Would that be 5 volts or 3.3 volts? (side question, how do I know which pins are 5v and which are 3.3v?)
Thanks. I think I can guess the direction this thread will go, but I figured I might as well ask anyway.