# I need help with this transfer function.

Discussion in 'Homework Help' started by dimatizer, Dec 1, 2012.

1. ### dimatizer Thread Starter New Member

Dec 1, 2012
3
0

Vout is across Vc2

Last edited: Dec 1, 2012
2. ### WBahn Moderator

Mar 31, 2012
18,093
4,918
#1) What help do you need?

#2) What efforts have you made to work the problem?

3. ### dimatizer Thread Starter New Member

Dec 1, 2012
3
0
G(s)= (3RCS+(RCS)^2+1)/[(SC)^2)(RSC+2)^2]

I achieved this answer by doing VC2=I2/CS=(Inot/cs)(1/SRC+2) and
Vin=(Inot)(Z) were Z is the equivalent impedance and my Transfer function is Vc2/Vin

I need help figuring out what I'm doing wrong because I don't believe I'm getting the right answer

4. ### WBahn Moderator

Mar 31, 2012
18,093
4,918
Without commenting (yet) one whether you are right or wrong, why is it that you believe you aren't getting the right answer? What have you done to check you answer?

5. ### dimatizer Thread Starter New Member

Dec 1, 2012
3
0
i found the transfer function of just the left circuit to be 1/(1+RCS) . i believe the right answer should be [(1/(1+RCS))(1/(1+RCS))]

6. ### blah2222 Well-Known Member

May 3, 2010
565
33
Also, it would help if you used LaTeX formatting to read these equations easier.

http://en.wikibooks.org/wiki/LaTeX/Mathematics

$
G(s)\ =\ \frac{3RCS+(RCS)^{2}+1}{(SC)^{2}(RSC+2)^{2}}
$

Is a lot easier to read than:

G(s)= (3RCS+(RCS)^2+1)/[(SC)^2)(RSC+2)^2]

Now, I have not verified if this is indeed correct but for the sake of making it easier to read. Click "quote" to see the formatting.

7. ### ramancini8 Member

Jul 18, 2012
447
119
Look to the left of the dotted line and calculate the Thevenin equivalent circuit. Replace the stuff to the left with the TEC, and use the voltage divider rule to calculate the voltage across C2.