(I'm kinda new to all this stuff so sorry if I say anything wrong)
If I use a 3.7v Lithium Ion Polymer Battery,
(Found at Adafruit) connected to a 5v Pro Trinket (Also found at Adafruit), will I be able to run a 5v motor off of this? To connect them, I would use this, (Pro Trinket Battery Pack)
Like I said, I'm new to this so I'm kind of confused. The information on the board makes me think it is 5v but how could there be 5v from a 3.7v battery? If someone could explain if this is possible it would be greatly appreciated.
There is no magic, so don' be confused. You cannot use magic to get voltages more than you input to the Arduino. AND you can't run motors from an Arduino. Don't try unless you have a closet full of Arduinos.
More study required.
I wouldn't try it for anything "important"...
The ATmega chip is rated down to 1.8V, but I think you have to reduce the clock speed.
And, a battery isn't like a gas tank... The voltage drops over time. It's better to use a higher-voltage through the voltage regulator so you can maintain 5V even as the battery is drained.
The Adafruit website says "many times" you can get-away with it:
Ideally, this backpack is for use with the 3.3V Pro Trinkets & ItsyBitsy, so that the battery voltage (3.7V-4.2V) will get regulated down to 3.3V on the board. However, many times, you can run a 5V microcontroller + accessories off of the ~4V from the LiPoly battery with no problem. (Technically its overclocking but we've never seen that affect the microcontroller itself, AVRs are happy to overclock without complaint).
The Trinket board is designed to run at 16 MHz on 5V and is not guaranteed to run at 3.7V.
The motor will run on 3.7V, but you must use a motor driver of some sort.