So I am considering buying a 5V Noctua computer fan to be controlled with an Arduino Etherten. The one on the amazon website (linked below) says that it's 3 wire PWM and 5V.
My question is, how do I control it with an Arduino? I assume I just connect the power and ground to the Arduino's power and ground and the signal pin to one of the digital pins, but I'm not sure exactly how to control it in the code. I am using a 1.5A 12V power supply.
Here's a link to the fan: https://www.amazon.com/Noctua-Cooling-Bearing-NF-A4X10-FLX-5V/dp/B00NEMGCIA/ref=sr_1_fkmr0_1?s=electronics&ie=UTF8&qid=1490147513&sr=1-1-fkmr0&keywords=noctua+4+pin+5V+fan
Supply the fan with its own voltage and just share the ground with your arduino.
Then the PWM pin should do the rest.
Do you know what the range of the pwm pin is ?
just in case to have to step it up or down in some way.
Can't I just use the arduino's 5V and ground? The fan only uses 50mA and my power supply is 12V so I can't supply it from elsewhere.
I don't know the PWM range (it's an Atmega 328P chip like the Uno...). Is it necessary to step it up or down?
Using the supply from the Arduino is never really advisable except for many known sensors and loads.
Split your positive supply to give the fan its own. constant supply.
Sorry I meant the "pwm range" of the fan itself.
Step up or down will rely on the details of the fan which I don't have here.
I have similar project coming up that will involve a few 12 volt fans and an atmosphere detector to switch one or more on.
For that I am using the common mosfet modules as they are a better method.