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Next: Sinusoids Up: Collected Problems Previous: FIR Filter

Circuits

Consider the DC circuit in the diagram below:

graphnewbox graphtempnewdimen = =by 1by 2 by .5exby 1.083in to 0pt$\:$-$\:$ =.5exby 0.833in to 0pt$\:$Vs$\:$ =by -1by 2 by .5exby 0.583in to 0pt$\:$+$\:$ =by 1by 2 by .5exby 0.167in to 0pt$\:$R1$\:$ =by -1by 2 by .5exby 0.083in to 0pt$\:$I1$\:$ =.5exby 0.833in to 0pt$\:$R2$\:$ =.5exby 0.400in to 0pt$\:$I2$\:$ =.5exby 0.833in to 0pt$\:$R3$\:$ =by -1by 2 by .5exby 0.583in to 0pt$\:$+$\:$ =.5exby 0.833in to 0pt$\:$V3$\:$ =by 1by 2 by .5exby 1.083in to 0pt$\:$-$\:$ =.5exby 0.400in to 0pt$\:$I3$\:$ depth1.603in width0pt height 0pt

1.
Determine a general expression for the current I1 and the voltage V3 as a function of the input voltage and the resistor values.
2.
Give numeric values for I1 and V3 if Vs=5V, $R_1=1K\Omega$, $R_2=R_3=2K\Omega$.
3.
Now consider the following AC circuit:
graphnewbox graphtempnewdimen = =by 1by 2 by .5exby 1.083in to 0pt$\:$-$\:$ =.5exby 0.833in to 0pt$\:$vs(t)$\:$ =by -1by 2 by .5exby 0.583in to 0pt$\:$+$\:$ =by 1by 2 by .5exby 0.167in to 0pt$\:$R1$\:$ =by -1by 2 by .5exby 0.083in to 0pt$\:$i1(t)$\:$ =.5exby 0.833in to 0pt$\:$R2$\:$ =.5exby 0.400in to 0pt$\:$i2(t)$\:$ =.5exby 0.833in to 0pt$\:$C$\:$ =by -1by 2 by .5exby 0.783in to 0pt$\:$+$\:$ =.5exby 0.833in to 0pt$\:$vc(t)$\:$ =by 1by 2 by .5exby 0.883in to 0pt$\:$-$\:$ =.5exby 0.533in to 0pt$\:$i3(t)$\:$ depth1.603in width0pt height 0pt
Assume that the input signal is a complex exponential, $v_s(t) = \exp(j 2\pi
ft)$. Then, the voltage vc(t) can be expressed in the form $v_c(t)= A \exp(j 2\pi
\hat{f}t + \phi)$. Determine the paramters A, $\hat{f}$, and $\phi$.
4.
What is the frequency response of this circuit?


next up previous
Next: Sinusoids Up: Collected Problems Previous: FIR Filter
Prof. Bernd-Peter Paris
2001-10-02