ADL5380-29A-EVALZ AD [Analog Devices], ADL5380-29A-EVALZ Datasheet - Page 29

• Manufacturer Part Number: ADL5380-29A-EVALZ
• Description: 400 MHz to 6 GHz Quadrature Demodulator
• Manufacturer: AD [Analog Devices]

As the load impedance of the filter increases, the filter design
becomes more challenging in terms of meeting the required
rejection and pass band specifications. In the previous W-CDMA
example, the 500 Ω load impedance resulted in the design of a
sixth-order filter that has relatively large inductor values and small
capacitor values. If the load impedance is 200 Ω, the filter design
becomes much more manageable. Figure 92 shows a fourth-order
filter designed for a 10 MHz wide LTE signal. As shown in Figure 92,
the resultant inductor and capacitor values become much more
practical with a 200 Ω load.
Figure 92. Fourth-Order Low-Pass LTE Filter Schematic
2.2µH
2.2µH
1.5µH
1.5µH
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Figure 93 and Figure 94 illustrate the magnitude response and
group delay response of the fourth-order filter, respectively.
Figure 94. Fourth-Order Low-Pass LTE Filter Group Delay Response
Figure 93. Fourth-Order Low-Pass LTE Filter Magnitude Response
–10
–15
–20
–25
–30
–35
–40
–5
5
0
0
0
5
5
10
10
FREQUENCY (MHz)
FREQUENCY (MHz)
15
15
20
20
25
25
30
30
ADL5380
35
35
40
40