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Design >> RF Design >> Why the two circuits have equal output impedance?
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Message started by baab on Oct 5^th, 2013, 8:37pm

Title: Why the two circuits have equal output impedance?
Post by baab on Oct 5^th, 2013, 8:37pm

Hi,
I am reading about noise in Design of Analog CMOS Integrated Circuits [Behzad Razavi].
Please help me with this question. Thank you.

Title: Re: Why the two circuits have equal output impedance?
Post by baab on Oct 5^th, 2013, 8:38pm

Sorry for the post. I can't attach more than one image in a post. Please ignore this post.

Title: Re: Why the two circuits have equal output impedance?
Post by raja.cedt on Oct 6^th, 2013, 3:58am

Dear Baab,
those two are similar circuit with noise current souse in one case and noise voltage source in one case. Otherwise open the current source and short the voltage source.

My sincere advice, for noise razavi book little bit confusing and complicated, so better you derive all for first time learning.

.....Raj.

Title: Re: Why the two circuits have equal output impedance?
Post by baab on Oct 6^th, 2013, 4:50am

Thank you, Raj. :)

Quote:

My sincere advice, for noise razavi book little bit confusing and complicated, so better you derive all for first time learning.

Sorry for asking this, because of my limited knowledge English. I am not sure what you mean "derive" here.
Did you mean that I should derive all formulas and proofs it myself to get a comprehensive understanding?