AN-1151 Application Note

AN-1151
Application Note
One Technology Way • P.O. Box 9106 • Norwood, MA 02062-9106, U.S.A. • Tel: 781.329.4700 • Fax: 781.461.3113 • www.analog.com
Using a Johanson 2450BM14E0007 Impedance-Matched, Integrated Filter Balun
with the ADF7241 and ADF7242
by Mary O’Keefe
INTRODUCTION
EVALUATION BOARD LAYOUT
This application note describes the use and performance achieved
using the Johanson Technology, Inc., 2450BM14E0007 impedancematched (complex differential impedance value) filter balun with
the ADF7241 or ADF7242 2.4 GHz RF transceivers. The filter
balun from Johanson Technology effectively reduces the RF
front-end component count and layout space. This balun is 100%
RF tested by Johanson Technology. The Additional Information
from Johanson Technology section provides more insight about
how harmonic emissions are attenuated, as well as further details
about the balun component.
An outline of the RF board layout is shown in Figure 1. Gerber
files of the board layout are available on the Analog Devices, Inc.,
ADF7242 evaluation board product website. Because the impedance seen by the balun is inherently dependent on the layout,
it is recommended to follow the EVAL-ADF724xDB3Z layout
as shown in the Gerber files as closely as possible for optimum
performance.
The board schematic is shown in Figure 2. Note that the C7 and
C8 capacitors are required for power amplifier stability, and the
specified 10 nF value should be used.
Table 1. Key Parameters of the Filter Balun
Parameter
Part Number
Frequency
Unbalanced Port Impedance
Balanced Port Impedance
Description
2450BM14E0007
2400 MHz to 2500 MHz
50 Ω
Matched to ADF7241/ADF7242
RF port impedance
TYPICAL PERFORMANCE DATA
Table 2 shows typical performance data obtained from the
ADF7241 and ADF7242 using the 2450BM14E0007 impedancematched filter balun.
Table 2. Typical Performance of the ADF7241 and ADF7242
Using the 2450BM14E0007 Filter Balun
Value
3 dBm
−50 dBm
−47 dBm
10634-001
Parameter
Tx Output Power
Harmonics
4.9 GHz
7.35 GHz
Figure 1. EVAL-ADF724xDB3Z Board Layout Highlighting Balun Location
Rev. 0 | Page 1 of 8
AN-1151
Application Note
TABLE OF CONTENTS
Introduction ...................................................................................... 1
Revision History ................................................................................2
Typical Performance Data ............................................................... 1
Evaluation Board Schematic ............................................................3
Evaluation Board Layout ................................................................. 1
Additional Information from Johanson Technology ....................4
REVISION HISTORY
5/12—Revision 0: Initial Version
Rev. 0 | Page 2 of 8
Application Note
AN-1151
10634-002
EVALUATION BOARD SCHEMATIC
Figure 2. EVAL-ADF724xDB3Z Schematic
Rev. 0 | Page 3 of 8
AN-1151
Application Note
ADDITIONAL INFORMATION FROM JOHANSON TECHNOLOGY
The following content and logos are provided courtesy of Johanson Technology, Inc. Johanson Technology is an independent corporation
and is not owned by, controlled by, or an affiliate of Analog Devices, Inc. Analog Devices, Inc., makes no representations or warranties
with respect to the Johanson 2450BM14E007 or any other Johanson Technology products.
High Frequency Ceramic Solutions
2.4 GHz Im pedance-Matched Balun-Filter Integrated Passive for ADF7241 and AADF7242
Detail Specification:
P/N 2450BM14E0007
5/15/2012
Page 1 of 3
General Specifications
Part Num ber
2450BM14E0007
Frequency (MHz)
2400 - 2500
50 Ω
Unbalanced Impedance (Antenna Out)
Insertion Loss
1.5 dB max.
Return Loss
9.5 dB min.
180° ± 10°
Phase Difference
Balanced Differential Im pedance
Conjugate match to ADI
ADF7241 and ADF7242
Am plitude Difference
2.0 dB max.
Attenuation (dB)
[email protected]~5000MHz
[email protected]~7500MHz
Operating Tem perature
-40 to +85°C
Pow er Capacity
2W max.
Recom m ended Storage
Tem perature
+5 to +35°C, Humidity:
45-75%RH, 18 mos. Max *
Reel Quanity
4,000
*18 months in vacuum sealed bag and 1 week cumulative after opened. For more info go to www.johansontechnology.c om/silverleads .html
Packaging
Style
P/N
Suffix Termination Style
Bulk
Suffix = S
T & R (Paper)
Suffix = E
Eg. 2450BM14E0007S
Eg. 2450BM14E0007T
AgPt
Suffix = None
Eg. 2450BM14E0007(S or T)
Term inal Configuration
No.
Function
1
Mechanical Dimensions
In
mm
c
Unbalanced Port
2
GND
3
Balanced Port
L
0.063 ± 0.004
1.60 ± 0.10
4
Balanced Port
W
0.031 ± 0.004
0.80 ± 0.10
5
GND
T
0.024 ± 0.004
0.60 ± 0.10
6
GND
a
0.008 ± 0.004
0.20 ± 0.10
b
0.008 +.004/-.006
0.20 +0.1/-0.15
c
0.006 ± 0.004
0.15 ± 0.10
g
0.012 ± 0.004
0.30 ± 0.10
p
0.020 ± 0.002
0.50 ± 0.05
W
L
a
p
3
2
1
4
5
6
T
g
b
Mounting Considerations
Mount these devices w ith brow n mark facing up.
* Line w idth should be designed to provide 50 Ω
0.25
impedance matching characteristics.
10nF caps (f or
DC-Block)
Solder Resist
Land
ADF724X
Units: mm
0.3
0.55
Through-hole
( f 0.2/0.35)
*
SAC 305 Solder Paste Recommended
0.25
Units: mm
Johanson Technology, Inc. reserves the right to make design changes w ithout notice.
All sales are subject to Johanson Technology, Inc. terms and conditions.
www.johansontechnology.com
4001 Calle Tecate • Camarillo, CA 93012 • TEL 805.389.1166 FAX 805.389.182
2012 Johanson Technology, Inc. All Rights Reserved
Rev. 0 | Page 4 of 8
Application Note
Preliminary
AN-1151
High Frequency Ceramic Solutions
2.4 GHz Impedance-Matched Balun-Filter Integrated Passive for ADF7242
P/N 2450BM14E0007
Detail Specification: 02/15/12
Page 2 of 3
Layout Details
)
)
)
)
)
)
Johanson Technology, Inc. reserves the right to make design changes without notice.
All sales are subject to Johanson Technology, Inc. terms and conditions.
www.johansontechnology.com
4001 Calle Tecate • Camarillo, CA 93012 • TEL 805.389.1166 FAX 805.389.1821
2012 Johanson Technology, Inc. All Rights Reserved
Rev. 0 | Page 5 of 8
AN-1151
Application Note
High Frequency Ceramic Solutions
Preliminary
2.4 GHz Impedance-Matched Balun-Filter Integrated Passive for ADF7242
P/N 2450BM14E0007
Detail Specification: 02/15/12
Page 3 of 3
Typical Electrical Performance (T=25°C)
0
)
-10
Insertion Loss
Return Loss
dB(RL)
dB(IL)
)
-20
-30
-40
-50
2
3
4
5
)
7
8
freq, GHz
200
20
)
10
)
0
)
100
0
-100
-10
-20
2.0
2.5
dif_Phase
dif_Amplitude
6
-200
3.0
freq, GHz
Actual Picture:
Johanson Technology, Inc. reserves the right to make design changes without notice.
All sales are subject to Johanson Technology, Inc. terms and conditions.
www.johansontechnology.com
4001 Calle Tecate • Camarillo, CA 93012 • TEL 805.389.1166 FAX 805.389.1821
2012 Johanson Technology, Inc. All Rights Reserved
Rev. 0 | Page 6 of 8
Application Note
AN-1151
NOTES
Rev. 0 | Page 7 of 8
AN-1151
Application Note
NOTES
©2012 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
AN10634-0-5/12(0)
Rev. 0 | Page 8 of 8