I want to use a MOSFET as a switch driven by my microcomputer.
The original circuit using N-channel MOSFET is on the left side. Honestly, I do not understand the choice of the IRLZ44. The circuit is designed for Arduino, which has 5V logic. Which means that for GPIO=True=5V, MOSFET opens and lets the current into the load.
However I have two problems:
- I am using Raspberry Pi, which has 3.3V logic. According to available information 3.3V is not enough to fully open MOSFET.
- I want my load to be connected to the ground (I had to do some voltage measurements).
I know enough electronics to assume that using P-channel MOSFET, as shown on the right side, might solve both of my problems at one stroke. For GPIO=False=0V MOSFET will be fully open, while GPIO=True=3.3V puts -1.7V on the MOSFET gate and practically close it down. If that does not suffice, I could also put GPIO into the listening mode and therefore pull the MOSFET gate to 5V.
Could you please tell me if the idea will work? And what IRLZ44-equivalent P-channel MOSFET should I use?