Help identifying an smd component

[newbie666]

Hello,

I need help with identifying the three legged (sot-23?) SMD component from the photo attached to this post. I'm fairly certain that it's a transistor (but not sure of the type).
I've measured 1-2mV on pints 1 and 3 and 5V on pin 3. Again, by looking at the circuit pin 3 may be a gate.

How can one figure out component type based on the marking? What's the deal with this rotated N (or a Z)? Is this a special kind of clue?

Thanks for help!

[selcuk]

It can be a diode to limit the input voltage to the opamp. Check CH0420LSPT in this page for example.

https://smd.yooneed.one/code4238.html