I'm designing a pcb with a 3.3v mcu and some 5.5++V modules on it. My microcontroller is doing the power-management, turning the 5.5V supply on/off. But I'm not sure how to turn the "high" voltage supply on/off from the mcu(GPIO).
The 5.5V is from a battery and is powering some modules(GSM/GPS) with internal regulators, so supplier encouraged "raw" battery-voltage so they can consume the current they need. I would like to be able to power these modules off completely(ultra-low-power system) when they aren't in use, often hours/days at a time.
The mcu is also powered from the battery, but via its own 3.3v LDO reg, and should always be powered on.
My knowledge in analog electronics is basic and limiting :p How to I enable the power-supply to one part of the circuit using my 3.3V mcu? Is a MOSFET the way to go? I would like to avoid a relay and other large components.
EDIT: Link for the Datasheet(GSM) The power-off current is 40µA, and would almost triple my idle current consumption if left on.