great question! so historically microcontrollers (and sensors) were 5V 'CMOS' power and logic. this was way better than the up-to-12V for TTL logic but over time the desire for higher clock speeds / faster IO / lower power means the voltage needs to drop (since power = current * voltage lower voltage is lower power) the next voltage standard became 3.3V. these days, even 3.3V is a 'bit high' and we're seeing lots of device that are 1.8V or 1.65V or even 1.2V max (yeek!) one thing we do for all of our sensor breakouts is add level shifting up/down as necessary so they work with EITHER 5V older boards (yay no need to throw them out!) or with the newer 3.3V boards (woo forward compatibility) level shifting and regulation also reduces the risk of damage from over/under volting or plugging stuff in backwards. this is documented here: https://learn.adafruit.com/introducing-adafruit-stemma-qt/st...

maybe someone from sparkfun could post advice for you here too...