I am learning Tina and drew this simple MOSFET switch:
Adjusting P1 will at a certain point switch on the MOSFET, which I expected to saturate immediately. However when I look at the DC transfer characteristic, it turns on 'slowly' when the gate voltage moves between 3.5V and 4.7V
I confirm this by setting P1 to 4.3%, where the MOSFET seems to be half-conducting and thus dissipating 249W:
How can this be? I thought that this kind of MOSFET was a switch but it seems to behave like a BJT (albeit in a narrow gate voltage range)?
EDIT: Thanks to for the answers, all +1, which thoroughly enlightened me; I accepted Andy's answer simply because it corresponded best to my lack of understanding.