Transcript Multi-functional Packaged Antennas for Next

Quiz, HW, and overall (so far) performances
Quiz 4 Performance
HW 5 Performance
25
90
80
20
70
60
15
50
Series1
40
30
20
Series1
10
5
10
0
0
1
2
3
4
5
6
7
8
9
10 11 12
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
Overall Performance
(out of 58)
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Example
Magnitude of Av(f):
Magnitude Plots
In decibels,
Phase Plots
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FET Common Source Amplifier model at High Frequencies
where
Thus to obtain higher value of upper freq:
1. Reduce Cgs and Cds
2. Reduce Rsig and RL
The Miller Effect
Section 8.3
For large voltage gains Av, the Zout, Miller  Zf. Thus, we can calculate Av, and finally calculate
the modified input impedance Zin, Miller.
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Note that the value of the input impedance depends on the load impedance, due to the influence of the feedback resistance
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Miller effect applied to feedback capacitances
The feedback impedance is given as :
The Miller impedance reflected
across the input terminals is :
Zf 
Zin,Miller 
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jC f
1
jC f 1  Av 
Thus, due to Miller effect a small capacitor can manifest as a large capacitor across the input terminals, if the amplifier
has a huge gain.
Note that a RC low
pass filter is formed by
Rsig and Ctotal
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Example for high frequency analysis of Common Source Amplifier
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