Imput impedance

Discussion in 'Homework Help' started by omar-rodriguez, Feb 13, 2016.

Jun 24, 2015
51
2
Hello,I have a very basic question ¿What's the imput impedance on this circuit?

I'm not sure if it is Zin=Vsignal/i or Zin=Va/i ?

Last edited: Feb 13, 2016
2. WBahn Moderator

Mar 31, 2012
17,777
4,804
Why do you think it might be Va/i?

Jun 24, 2015
51
2
because I believed that with imput, they are talking about all the input branch

Last edited: Feb 13, 2016
4. WBahn Moderator

Mar 31, 2012
17,777
4,804
First, the word is "input", not "imput".

What is are the input terminals for this circuit?

Jun 24, 2015
51
2
I'm sorry I don't speak English I'm just trying... now I understand your point it is Zin=Vsignal/i, because Vsignal is the input

6. WBahn Moderator

Mar 31, 2012
17,777
4,804
Don't worry -- you're English is far better then my (fill-in-your-native-tongue-here).

Correct. Vsignal is the input voltage and i is the input current. The ratio between them is therefore the input impedance.

Though there are really two input impedances -- large signal and small signal; but I don't know if you have gotten to that yet.