Well hello there,
I have 3v3 MCU with 5V tolerant IO and want to drive
these puppies to switch 5V.
I thought I can just pullup MCU pin to 5V like in my first example below, but boy I was wrong – it seems MCU pin acts as a ground for those 1.7V that are above MCUs 3.3V and I'm getting only 3.3V still (correct me if I'm wrong understanding why I'm getting 3.3V). So, my next solution would be to use cheapo darlington transistor array like
this one Potential problem with using array is that Pfets gates will get it's power entirely from pullup resistor, so I assume resistor have to be low value for fast switching, that means more wasted power and loosing power is an issue... I don't have experience driving Pfets, so I hope someone with experience will give his 2cents.
Pfets will be switched up to 200 times a second (not PWM) and a bit of "lag" is not an issue cos between switches I2C communication has to happen. Switching current up to 1A.
I'm not happy I need extra chips to drive them at all, but as I have 7 Pfets adding one darlington array is'nt end of the world. This is hopefully a comercial product, so component and an assembly price does matter.
P.S. I have next to me working 2nd example in the picture, Pfets seems to be a bit slow switching cos I'm using 10K pullups for now. Will test lower values. Sadly I don't have fancy oscilloscope to test this so I'm eye balling

Thank you for your time reading and hopefully helping
DON'T MIND FLIPPED FET CONNECTIONS