Electronic Components Datasheet Search
  English  ▼

Delete All
ON OFF
ALLDATASHEET.COM

X  

Preview PDF Download HTML

ADL5523 Datasheet(PDF) 20 Page - Analog Devices

Part No. ADL5523
Description  Low Noise Amplifier
Download  21 Pages
Scroll/Zoom Zoom In 100% Zoom Out
Maker  AD [Analog Devices]
Homepage  http://www.analog.com
Logo 

ADL5523 Datasheet(HTML) 20 Page - Analog Devices

 
Zoom Inzoom in Zoom Outzoom out
 20 / 21 page
background image
ADL5523
Data Sheet
Rev. C | Page 20 of 21
S11 OF THE LNA WITH S22 MATCHED
To determine the correct matching circuit for optimal noise,
look at the results of S11 for the various frequencies at which
S22 was tuned earlier in the Tuning S22 section. Once S11 is
determined for a particular frequency, find the matching
components that provided that match. Figure 63 and Figure 64
show S11 for the various frequencies. Again, these measurements
are all based on S22 being matched at that particular frequency.
Note that, for the examples shown in Figure 63 and Figure 64, S11
is either in the lower left quadrant of the Smith Chart or slightly
into the upper left. To move the impedance in the given noise
circle, a series L component at the LNA input is required. The L
values in the examples differ but a correct L value moves the match
along the constant R circle up into the upper left quadrant of the
Smith Chart.
A shunt capacitor can then be added to move the match along a
constant admittance line, down and to the right, directly into
the center of the noise circle given in Figure 61.
The solution for the structure of the match for the examples in
Figure 63 and Figure 64 is a series L to the input of the LNA
and a shunt capacitor at the generator end of this inductor. The
recommended components for matching at various frequencies
are shown in Table 7.
An example of the effect of the series L, shunt C match, based
on the 800 MHz example, is given in Figure 62. This example
uses the output from the Agilent ADS Smith Chart tool.
Figure 62. Example of Series L, Shunt C Matching Network for ΓOPT
M2
M1
FREQUENCY (400MHz TO 4GHz)
M1
FREQUENCY 400MHz
S11 = 0.877/–44.639
IMPEDANCE = Z0 × (0.443 – j2.365)
M2
FREQUENCY 2GHz
S11 = 0.615/–170.569
IMPEDANCE = Z0 × (0.240 – j0.078)
Figure 63. S11 of ADL5523 with S22 Matched at 2 GHz
M2
M1
FREQUENCY (400MHz TO 4GHz)
M1
FREQUENCY 400MHz
S11 = 0.864/–40.186
IMPEDANCE = Z0 × (0.594 – j2.615)
M2
FREQUENCY 3.2GHz
S11 = 0.595/163.164
IMPEDANCE = Z0 × (0.259 + j0.138)
Figure 64. S11 of ADL5523 with S22 Matched at 3.2 GHz


Html Pages

1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17  18  19  20  21 


Datasheet Download




Link URL




Privacy Policy
ALLDATASHEET.COM
Does ALLDATASHEET help your business so far?  [ DONATE ]  

About Alldatasheet   |   Advertisement   |   Datasheet Upload   |   Contact us   |   Privacy Policy   |   Alldatasheet API   |   Link Exchange   |   Manufacturer List
All Rights Reserved© Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn