I’ve been trying to switch a HC-05 Bluetooth module on and off with a 3,3V Pro Mini.
I need to be able to switch it off because this is a battery-powered application.
There’s a circuit diagram of my current circuit attached. As you can see I am using a P-CH Mosfet as a high side switch to toggle VCC of my HC 05. The Mosfets Source is connected to 3,3V and a NPN Transistor is used to pull it’s Gate to GND and essentially switch the Mosfet on.
So far this seems to work. When I connect VCC directly to the pin the power led of the HC05 lights up and it starts working - great!
However the Pro Mini seems to be unable to drive the Mosfet.
When it tries to set Pin 7 to HIGH, it reboots the µC and begins its code from the start.
Does anyone has an idea what the reason could be?
Maybe bad resistor values that makes the circuit draw too much power from the pin? I can’t seem to get it working.
Here are the datasheets of the NDP 6020 P and the BC548C in case you want to have a look: