Seeing as how the the LCD serial Backpack recommends 6-7V would it be possible to have a boost converter that supports 5/3.3V inputs as well as a direct 6-7V input?
It wouldn’t have to be an high efficiency one perhaps just a In-cap the inductor a logic level Mosfet, schotky diode, and Cap-out and use a PWM pin from the micro to produce the needed frequency and duty cycle for the Boost converter.