I have been trying to research via google on what would be needed to power LEDs with an external power source and control them via the Arduino.
The video I have found online (https://www.youtube.com/watch?v=2YDTxvEWENY) gives me a rough idea on what needs to be done. What I am struggling with is what would be the correct transistor to purchase?
https://www.sparkfun.com/products/10213 ← I believe this is what he is using in the video?
https://www.sparkfun.com/products/100 ← but could I use this as I already have one?
https://www.sparkfun.com/products/8928 ← Or could I use this?
Picking the LED driver depends on the amount of current the LEDs require. If you decide to use the relay, you will need a transistor to drive its coil. The 8928 should work. The 8928 can handle a max of 100mA, so that transistor can handle a few LEDs. The 10213 N-channel MOSFET handles up to 30A, so I assume that should be more than enough. To use the MOSFET, connect a 10K resistor from the Gate to the Source, and connect the Source to Ground. Your LED power supply’s Ground (or ‘-’ lead) needs to be connect to Ground as well. Connect the Gate to the Arduino. Connect the Drain to the negative side of the LEDs. Connect the positive end of the LEDs to a current limiting resistor, and the other end of that resistor to the positive side of the LED power supply.
Thanks, it seems the most economical choice would be either the MOSFET or the 8928.
For the MOSFET is pretty obvious the limits specified but which value on the data sheet specifies the voltage to close the circuit? Also curious what the difference between an N channel and P channel is?
For the 8928, those limits are located on the data sheet at Collector-Base Voltage, Collector-Emitter Voltage and the Collector Current? The Emitter-Base Voltage is the voltage to close the circuit?
Update: Just googled the N and P, looks like it is positive and negative…one goes before the “load” and the other goes after the “load” I guess you could say.