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VinnyCee
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Homework Statement
http://img252.imageshack.us/img252/410/prelab4problem1tz5.jpg
Find transfer function of the circuit above (i.e. - [itex]\frac{V_o(s)}{V_i(s)}[/itex])
[tex]\frac{V_o(s)}{V_i(s)}\,=\,\frac{a_1}{s^2\,+\,a_2\,s\,+\,a_3}[/tex]
1) Find a1, a2, a3 in terms of R, C1 and C2
2) Given that [itex]C_1\,=\,100\,\mu\,F[/itex] and [itex]R\,=\,10\,K\Omega[/itex], find [itex]C_2[/itex] such that the system has a pair of complex conjugate poles located at [itex]-1\,\pm\,j\,\sqrt{399}[/itex].
Homework Equations
KCL, OP Amp rules, complex numbers.
The Attempt at a Solution
Ok, I went through a nodal analysis, I'm not going to post the steps here, but here are the results...
[tex]\frac{V_o}{V_i}\,=\,\frac{1}{C_1\,C_2\,R\,s^2\,+\,2\,C_2\,R\,s\,-\,1}[/tex]
[tex]\frac{V_o}{V_i}\,=\,\frac{\frac{1}{C_1\,C_2\,R}}{s^2\,+\,\frac{2}{C_1}\,s\,-\,\frac{1}{C_1\,C_2\,R}}[/tex]So that means that...
[tex]a_1\,=\,\frac{1}{C_1\,C_2\,R}[/tex]
[tex]a_2\,=\,\frac{2}{C_1}[/tex]
[tex]a_3\,=\,\frac{1}{C_1\,C_2\,R}[/tex]
That's for part one, does that seem right?For part two, we want to MAKE the roots of the following equation (denominator):
[tex]s^2\,+\,2000\,s\,+\,\frac{1}{C_2}\,=\,0[/tex]
EQUAL TO...
[tex]-1\,\pm\,j\,\sqrt{399}[/tex]
How do I make that happen?
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