What's the difference between pi hybrid and small signal equivalent circuits?

[EngUOL]

Hi everyone. I am starting to study transisors at Uni. and I am confuse in some main concepts. i thought about posting it here so someone can help me up. are pi hybrid signals equivalent circuits used with the same porposes as small signals equivalent circuits? or are pi hybrid signals, small signals??

sorry i know it might be sort of a stupid question. ill be very appreciated for any feedback

thankyou

 

[zoki85]

Yes, pi-hybrid model is for small signals. Another commonly used and equivalent model is T-small signal model.

 

[EngUOL]

thanks for your reply zoki

very appreciated