I understand that the more saturated a transistor is, it takes a longer time to turn off, but is there a way to calculate this? To calculate the turn on and off time? Or is a test circuit the only way?

 

Hello,
What is the need to know its time diag?

 

I understand that the more saturated a transistor is, it takes a longer time to turn off, but is there a way to calculate this? To calculate the turn on and off time? Or is a test circuit the only way?

If there is a way to predict any of these things mathematically, I've never seen it; turn-on time, rise time, storage time and fall time all depend heavily on operating conditions and individual device characteristics. IMO, the best information would probably come from the device spec sheet backed up with experimental data taken under realistic operating conditions.

That's the approach I would take, anyway...

 

Look at the data sheet, for example the 2n4401.

There is always simulation...

 

Hello,
What is the need to know its time diag?

To help me figure out this http://forum.allaboutcircuits.com/threads/mosfet-driver-question.109687/

I know about data sheets, I read them. But often times I want to know the reaction times of the transistor at different parameters than specified. That's why I asked about calculating.