Hi, I tried to simulate mosfet switch for 2x10W LEDs, but there is a huge voltage drop on the mosfets. Why 5V logic signal can't open mosfet?
LEDs specs: 10V 1A

 

What type of MOSFET (part number)?

What is the load?

 

What type of MOSFET (part number)?

What is the load?

And what is the gate voltage on the yellow MOSFET?

 

There is no model of the mosfet. Only params.
Drain voltage 9.3V
Load - 2 LEDS (10V 1A)

 

Your MOSFET is way too small for this load and drive combination.

 

Where can I find real mosfet crystal size? I use ao3400 in my project, but this information is not presented in datasheet

 

Where can I find real mosfet crystal size? I use ao3400 in my project, but this information is not presented in datasheet

That's never given in the data sheet.
For discrete MOSFETs you look at the voltage rating, the on-resistance, and the voltage at which the on-resistance is measured, when they are used as a switches.