I am working on a GPS test board. It is running on a battery and in order to save energy I want to switch off the GPS module controlled by a 328.
- Single power source on board
- Using a GPS module which required 2 power supplies
- One for Vcc (normal operation)
- One for backup power (V-backup)
Now I was thinking to use a transistor to switch the Vcc ON/OFF. Normally in such scenario the load (GPS module) is on the collector side.
The challenge here is that the V_backup uses the same power source (common round) and for that the ground needs to be connected :-( (meaning the Emmitter ground is useless).
See attached sketch
Any suggestions on how to get this up and running?