AN302 - BGS22WL10

B GS 22WL 10
Per for man ce of D P D T ( Dual -P ole /
Dou ble - Th row ) RF M O S s witc h
Bro adb an d Di ffe ren tial L TE , WC D M A,
CD MA, U MT S M obi le Di v ers i t y
Applic atio ns
Applic atio n N ote A N 302
Revision: Rev. 1.0
2012-11-29
RF and P r otecti on D evic es
Edition 2013-06-26
Published by
Infineon Technologies AG
81726 Munich, Germany
© 2013 Infineon Technologies AG
All Rights Reserved.
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BGS22WL10
Broadband Diffential Diversity Applications
Application Note AN302
Revision History: 2012-11-29
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Subjects (major changes since last revision)
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Application Note AN302, Rev. 1.0
3 / 27
2012-11-29
BGS22WL10
Broadband Diffential Diversity Applications
List of Content, Figures and Tables
Table of Content
1
Introduction ........................................................................................................................................ 6
2
2.1
2.2
2.3
Features .............................................................................................................................................. 7
Main Features ...................................................................................................................................... 7
Functional Diagram .............................................................................................................................. 7
Signal Description ................................................................................................................................ 8
3
3.1
3.2
3.3
Small Signal Characteristics Measurement Results ...................................................................... 9
Insertion Loss ....................................................................................................................................... 9
Return loss ......................................................................................................................................... 10
Isolation of inactive paths ................................................................................................................... 12
4
4.1
4.2
4.3
Switching time .................................................................................................................................. 14
Measurement Specifications .............................................................................................................. 14
Measurement Setup ........................................................................................................................... 15
Measurement results .......................................................................................................................... 16
5
5.1
5.2
5.3
Intermodulation ................................................................................................................................ 17
Test conditions ................................................................................................................................... 17
Measurement Setup ........................................................................................................................... 18
Measurement results .......................................................................................................................... 19
6
6.1
6.2
6.2.1
6.2.2
Harmonic Generation ....................................................................................................................... 20
Measurement setup ........................................................................................................................... 20
Measurement results .......................................................................................................................... 21
Low Band (824 MHz) ......................................................................................................................... 21
High Band (1800 MHz) ....................................................................................................................... 22
7
Power Compression Measurements .............................................................................................. 23
8
8.1
8.2
Application Board and Measurement desciption ......................................................................... 24
Application board................................................................................................................................ 24
Measurement description and deembedding ..................................................................................... 25
Author
26
Application Note AN302, Rev. 1.0
4 / 27
2012-11-29
BGS22WL10
Broadband Diffential Diversity Applications
List of Content, Figures and Tables
List of Figures
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Figure 7
Figure 8
Figure 9
Figure 10
Figure 11
Figure 12
Figure 13
Figure 14
Figure 15
Figure 16
Figure 17
Figure 18
Figure 19
Figure 20
Figure 21
Figure 22
Figure 23
Figure 24
Differential Band select Switching application ..................................................................................... 6
Functional Diagram .............................................................................................................................. 7
Pin configuration of BGS22WL10 ........................................................................................................ 8
Forward Transmission curves for all RF paths .................................................................................... 9
Return loss for active port 2 (2P/2N) .................................................................................................. 10
Return loss for active port 3 (3P/3N) .................................................................................................. 11
Isolation of Port 3 (3P/3N) by active Port 2 (2P/2N) .......................................................................... 12
Isolation of Port 2 (2P/2N) by active Port 3 (3P/3N) .......................................................................... 13
Switching Time ................................................................................................................................... 14
Rise/Fall Time .................................................................................................................................... 14
Switching Time Measurement Setup ................................................................................................. 15
Switching Time of BGS22WL10 ......................................................................................................... 16
Block diagram of RF Switch intermodulation ..................................................................................... 17
Test set-up for IMD Measurements.................................................................................................... 18
Set-up for harmonics measurement ................................................................................................... 20
nd
2 harmonic at fc=824 MHz ............................................................................................................... 21
rd
3 harmonic at fc=824 MHz ................................................................................................................ 21
nd
2 harmonic at fc=1800 MHz ............................................................................................................. 22
rd
3 harmonic at fc=1800 MHz .............................................................................................................. 22
Power Compression Measurement Results at fc=824 MHz ............................................................... 23
BGS22WL10 application board .......................................................................................................... 24
Layout of the application board and deembedding kit ....................................................................... 24
PCB layer information ........................................................................................................................ 24
SMA connector for deembedding procedure ..................................................................................... 25
List of Tables
Table 1
Table 2
Table 3
Table 4
Table 5
Table 6
Table 7
Table 8
Table 9
Table 10
Table 11
Table 12
Device desciption ................................................................................................................................. 6
Pin Description (top view) .................................................................................................................... 8
Truth table ............................................................................................................................................ 8
Insertion Loss of throw between port1 (1P/1N) and port2 (2P/2N) .................................................... 10
Insertion Loss of throw between port1 (1P/1N) and port3 (3P/3N) .................................................... 10
Return loss of active ports .................................................................................................................. 11
Isolation of Port3 (3P/3N) bby active port 2 (2P/2N) .......................................................................... 12
Isolation of Port2 (2P/2N) bby active port 3 (3P/3N) .......................................................................... 13
Switching time measurement results of BGS22WL10 ....................................................................... 16
Test conditions and specifications of IMD measurements ................................................................. 17
IMD products of Band I ...................................................................................................................... 19
IMD products of Band V ..................................................................................................................... 19
Application Note AN302, Rev. 1.0
5 / 27
2012-11-29
BGS22WL10
Broadband Diffential Diversity Applications
List of Content, Figures and Tables
1
Introduction
The BGS22WL10 RF MOS switch is specifically designed for differential diversity applications (e.g. Figure 1) in
low bands up to 3 GHz like 3G WCDMA diversity, CDMA diversity, UMTS diversity or LTE diversity RF frontend
system solutions. Therefore, the Insertion loss of the BGS22WL10 below 2 GHz is closed to 0.35 dB, upto 3
GHz the IL is in the range of 0.45 dB and the port to port Isolation is more than 26 dB. A typical application is to
combine two Rx paths in a mobile cellular device after the Rx filters or duplexers into one input to the tranceiver
IC. The IC can also be used for a wide variety of applications switching balanced signals in a frequency range of
0.1 - 3 GHz.
Diversity Switch
B3L
Diversity
Antenna
B7L
High Band
Low Band
B20L
B20L
Figure 1
Diversity Inputs
B1
DPDT
B1&B8
DPDT
B3L
UMTS/LTE
Transceiver
IC
Differential Band select Switching application
Unlike GaAs technology, external DC blocking capacitors at the RF Ports are only required if DC voltage is
applied externally. The BGS22WL10 RF Switch is manufactured in Infineon’s patented MOS technology,
offering the performance of GaAs with the economy and integration of conventional CMOS including the
inherent higher ESD robustness. This DPDT (Dual-Pole / Double Throw) RF MOS switch which combines two
differential signals into one differential output or splits one differential signal into two separate differential lines.
The parallel paths of the
switch are controlled simultaneously through the same signals. The switch is designed to operate in battery
powered applications with a supply voltage range of 2.4 - 3.6 V while the current consumption is below 300 μA.
The highly symmetric design ensures best phase- and amplitude accuracy.
The RF switch is packaged in a standard RoHS compliant TSLP-10-1 package with a small outline of only 1.55
x 1.15 mm².
Table 1
Device desciption
Product Name
Product Type
Package
Marking
BGS22WL10
DPDT RF Switch
TSLP-10-1
W2
Application Note AN302, Rev. 1.0
6 / 27
2012-11-29
BGS22WL10
Broadband Diffential Diversity Applications
List of Content, Figures and Tables
2
Features
2.1
Main Features











2.2
DPDT (Dual-Pole / Double-Throw) differential RF
switch
All ports fully symmetrical
High ESD robustness
Frequency range: 0.1 - 3 GHz
High signal power up to 30 dBm
Extremely low insertin loss
High port-to-port-isolation
Supply voltage 2.4 - 3.6 V
No decoupling capacitors required if no DC applied on
RF lines
Lead and halogen free package (RoHS and WEEE
compliant)
Small leadless package TSLP-10-1 with the size of
1.55 x 1.15 mm² and a maximum height of 0.77 mm.
Functional Diagram
BGS22W2L10
Port 2P
Port 1P
Port 3P
Port 2N
Port 1N
Port 3N
DPDT
ESD Protection
VDD
Figure 2
VCTRL
Functional Diagram
Application Note AN302, Rev. 1.0
7 / 27
2012-11-29
BGS22WL10
Broadband Diffential Diversity Applications
List of Content, Figures and Tables
2.3
Signal Description
Table 2
Figure 3
Pin Description (top view)
Pin NO
Name
Pin Type
1
Port 3P
I/O
Function
2
GND
GND
Ground
3
GND
GND
Ground
4
Port 2N
I/O
RF port 2N
5
Port 2P
I/O
RF port 2P
6
CTRL
I
Control Pin
7
Port 1P
I/O
RF port 1P
8
Port 1N
I/O
RF port 1N
9
VDD
Supply
10
CTRL
I
RF port 3P
Supply voltage
Control Pin
Pin configuration of BGS22WL10
Table 3
Truth table
Pin No.
Control
Port1 to Port2
0
Port1 to Port3
1
Application Note AN302, Rev. 1.0
8 / 27
2012-11-29
BGS22WL10
Broadband Diffential Diversity Applications
List of Content, Figures and Tables
3
Small Signal Characteristics Measurement Results
All measurement results of this application note are measured with a typical device of the BGS22WL10 on an
application board. The measurement procedure is shown in chapter 8 including the needed deembedding.
The small signal characteristics are measured at 25 °C, 0 dBm Pin, 3 Volt Vdd, 3 V Vcrlt up to 10 GHz with a
Network analyzer connected to an automatic multiport switch box in single ended mode. A differential simulation
is possible ba using a ideal trabnsformator inbetween the Port 1P to 1N, 2P to 2N and 3P to 3N thanks to the
full s-Parameter matrix of the BGS22WL10 which is provided @ Infinieon’s internet page.
In the following tables and graphs the most important RF parameter of the BGS22WL10 are shown. The
markers are set to the most important frequencies of the WCDMA system.
3.1
Insertion Loss
Insertion_Loss
10
1000 MHz 1710 MHz
-0.3632 dB -0.4109 dB
1910 MHz
915 MHz
-0.4226 dB
-0.3618 dB
5
2170 MHz
-0.4397 dB
824 MHz
-0.3479 dB
2690 MHz
-0.5038 dB
0
1N to 2N
1N to 3N
1P to 2P
1P to 3P
-5
-10
10
Figure 4
2010
4010
6010
Frequency (MHz)
8010
10000
Forward Transmission curves for all RF paths
Application Note AN302, Rev. 1.0
9 / 27
2012-11-29
BGS22WL10
Broadband Diffential Diversity Applications
List of Content, Figures and Tables
Table 4
Frequency
(MHz)
Insertion Loss of throw between port1 (1P/1N) and port2 (2P/2N)
824
915
1000
1710
1910
2170
2690
0.35
0.34
0.36
0.35
0.36
0.35
0.41
0.41
0.42
0.42
0.44
0.44
0.5
0.52
RF path
1P  2P
1N  2N
Table 5
Frequency
(MHz)
RF path
1P  3P
1N  3N
3.2
Insertion Loss of throw between port1 (1P/1N) and port3 (3P/3N)
824
915
1000
1710
1910
2170
2690
0.34
0.34
0.35
0.36
0.36
0.36
0.41
0.42
0.41
0.43
0.43
0.44
0.5
0.5
Return loss
Return loss Port1 to Port2 active
0
-10
-20
1N
2N
1P
2P
-30
-40
10
Figure 5
2010
4010
6010
Frequency (MHz)
8010
10000
Return loss for active port 2 (2P/2N)
Application Note AN302, Rev. 1.0
10 / 27
2012-11-29
BGS22WL10
Broadband Diffential Diversity Applications
List of Content, Figures and Tables
Return loss Port1 to Port3 active
0
-10
-20
1N
3N
3P
1P
-30
-40
10
Figure 6
Table 6
Frequency
(MHz)
2010
4010
6010
Frequency (MHz)
8010
10000
Return loss for active port 3 (3P/3N)
Return loss of active ports
port
824
915
1000
1710
1910
2170
2690
1P
-29.4
-29.8
-30.2
-30.7
-29.2
-32.7
-28.9
-30.9
-28.2
-28.6
-28.9
-30.7
-28.7
-37.6
-27.7
-29.8
-28.8
-28.6
-29
-31.4
-23.2
-31.6
-27
-29.3
-29.5
-27.6
-32.4
-27.1
-24.4
-32.4
-25.8
-31
-30.5
-28.3
-30.2
-27.4
-22.5
-26.6
-26
-29.3
-33.3
-28.6
-33.1
-27.7
-28.9
-23.9
-27.3
-29.5
-29.4
-22.4
-26.2
-21
-25.8
-31.5
-25.8
-27.5
Active Path
Throw port
1 to port 2
1N
2P
2N
1P
Throw port
1 to port 3
1N
3P
3N
Application Note AN302, Rev. 1.0
11 / 27
2012-11-29
BGS22WL10
Broadband Diffential Diversity Applications
List of Content, Figures and Tables
3.3
Isolation of inactive paths
Isolation_2N_2P_active
0
-20
-40
2690 MHz
-25.06 dB
-60
3P to 1P
3N to 1N
3N to 2P
3N to 1P
3P to 2P
3N to 2N
3N to 1N
3P to 2N
-80
100
Figure 7
2100
4100
6100
Frequency (MHz)
8100
10000
Isolation of Port 3 (3P/3N) by active Port 2 (2P/2N)
Table 7
Isolation of Port3 (3P/3N) bby active port 2 (2P/2N)
Port to port
isolation
824
915
1000
1710
1910
2170
2690
3P  1P
-36
-42.8
-45.6
-43.3
-42.8
-48.1
-45.3
-50.6
-35
-41.8
-44.6
-42.2
-42.2
-46.9
-44.4
-48.7
-34.3
-41.2
-43.6
-41.6
-41.4
-45.6
-43.8
-47.5
-33.1
-41.4
-40.1
-37.3
-36.5
-39.4
-39.8
-38.6
-29.6
-36.6
-37.1
-35.3
-34.3
-36.8
-37.1
-36.6
-27.7
-34.1
-34.1
-33.2
-31.7
-35.6
-34.6
-35.9
-25.1
-31.2
-31.7
-30.6
-27.2
-31
-30.1
-31.5
3N  1P
3P  1N
3N  1N
3P  2P
3P  2N
3N  2P
3N  2N
Application Note AN302, Rev. 1.0
12 / 27
2012-11-29
BGS22WL10
Broadband Diffential Diversity Applications
List of Content, Figures and Tables
Isolation_3N_3P_active
0
-20
-40
-60
2P to 1P
3P to 2N
2P to 1N
2N to 1N
3N to 2P
2N to 1P
3P to 2P
3N to 2N
-80
10
Figure 8
2010
4010
6010
Frequency (MHz)
8010
10000
Isolation of Port 2 (2P/2N) by active Port 3 (3P/3N)
Table 8
Isolation of Port2 (2P/2N) bby active port 3 (3P/3N)
Port to port
isolation
824
915
1000
1710
1910
2170
2690
2P  1P
-36.3
-42.5
-45.1
-42.5
-36
-48.5
-49
-46
-35.1
-41.3
-44.2
-41.2
-35
-47
-47.8
-45.1
-34
-41.1
-43.6
-40.1
-34
-45.3
-46.5
-44.3
-32.9
-39.4
-40.3
-34.8
-28.5
-37.9
-37.8
-37.7
-29.1
-35.6
-34.5
-33.7
-27.9
-35.9
-36
-35.1
-27.3
-34.4
-34.2
-31.7
-26.1
-33.2
-33.4
-34.1
-24.2
-31.5
-31.2
-29.5
-24.1
-30.2
-30.3
-30.9
2N  1P
2P  1N
2N  1N
2P  3P
2P  3N
2N  3P
2N  3N
Application Note AN302, Rev. 1.0
13 / 27
2012-11-29
BGS22WL10
Broadband Diffential Diversity Applications
List of Content, Figures and Tables
4
Switching time
4.1
Measurement Specifications
Switching On Time:
50% Trigger signal to 90 % RF Signal
Switching Off Time:
50% Trigger signal to 10% RF Signal
VCTRL
2
VCTRL
tON
90% RF signal
RF signal
tOFF
Figure 9
10% RF signal
Switching Time
Rise time: 10% to 90% RF Signal
Fall time: 90% to 10% RF Signal
90% RF signal
RF signal
tOFF
tON
Figure 10
10% RF signal
Rise/Fall Time
Application Note AN302, Rev. 1.0
14 / 27
2012-11-29
BGS22WL10
Broadband Diffential Diversity Applications
List of Content, Figures and Tables
4.2
Measurement Setup
Pulse Generator
Oscilloscope
1 kHz, 1.8 Volt
50 % Duty Cycle
1 MΩ input
VDD = constant,
3Volt
Vctrl
Vctrl
VDD
50 Ω
3P
2P
50 Ω
50 Ω input
50 Ω
BGS22WL10
RFOUT
2N
3P
1N
3 dB
50 Ω
1P
Signal Generator
RFIN
Rf Signal,
1 GHz, +10 dBm
50 Ω output
Figure 11
Switching Time Measurement Setup
The switching Time measurement setup consist of one pulse generator which generates a sqare wave with 50%
duty cycle and an amplitude of 1.8 Volts, an oscilloscope which can detect the 1 GHz signal and the 1 kHz
signal and one Signal generator which is set to an output signal of 1GHz with a power level 10 dBm.
If the oscilloscope can not detect the 1 GHz signal of the RF path, due to small bandwith, it is possible tu use a
cristal oscillator in front of the oscilloscope (such a device detects any RF signal present at input and
commutate that one) that the RF signal can be detected.
Application Note AN302, Rev. 1.0
15 / 27
2012-11-29
BGS22WL10
Broadband Diffential Diversity Applications
List of Content, Figures and Tables
4.3
Measurement results
RF rise time
Switching time
Figure 12
Table 9
Switching Time of BGS22WL10
Switching time measurement results of BGS22WL10
BGS22WL10
Application Note AN302, Rev. 1.0
RF rise time (ns)
Switching time (ns)
350
607
16 / 27
2012-11-29
BGS22WL10
Broadband Diffential Diversity Applications
List of Content, Figures and Tables
5
Intermodulation
5.1
Test conditions
Another very important parameter of a RF switch is the large signal capability. One of the possible
intermodulation scenarios is shown in Figure 13.The transmission (Tx) signal from the main antenna is coupled
into the diversity antenna with with high power.This signal (20 dBm) and a received Jammer signal (-15 dBm)
are entering the switch. Thank to the spezified application for the BGS22WL10 inbetween the filters and the
Transceiver, the Tx signal from the main antenna loose until arriving at the switch input moslty 5 to 10 or more
dB, depending of the filter and pcb structure of the RF frontend. The IMD products are measured with a Tx of
20dBm, which is corresponding to the IMD spec of a main antenna diversity switch like Infineons BGSF110GN.
Therefore, the measured IMD products will be extremly better in the spezified application circuit within the filters
and transceiver as showed in the measurement results below.
Coupled Tx
Signal from
main antenna
Jammer
(CW)
Receiver
Diversity
Antenna
RF Switch
IMD
Figure 13
Block diagram of RF Switch intermodulation
Special combinations of TX and Jammer signal are producing intermodulation products 2
nd
and 3rd order, which
fall in the RX band and disturb the wanted RX signal.
In Table 10 frequencies for 3 bands and the linearity specifications for an undisturbed communication are given.
Table 10
Test conditions and specifications of IMD measurements
Test Conditions
(Tx = +20dBm, Bl = -15dBm,freq.in MHz,@25°C)
Band
Tx Freq.
Rx Freq.
IMD2 Low
Jammer 1
850
836.5
881.5
45
791.5
1900
1880
1960
80
2100
1950
2140
190
Application Note AN302, Rev. 1.0
Linearity Specification
IMD3
IMD2 High
Jammer 2 Jammer 3
IM2
(dBm)
IIP2
(dBm)
IM3
(dBm)
IIP3
(dBm)
1718
-105
110
-105
65
1800
3840
-105
110
-105
65
1760
4090
-105
110
-105
65
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2012-11-29
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Broadband Diffential Diversity Applications
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5.2
Measurement Setup
The test setup for the IMD measurements has to provide a very high isolation between RX and TX signals. As
an example the test set-up and the results for the high band are shown (Figure 14 and Table 11).
For the RX / TX separation a professional duplexer with 80 dB isolation is used.
In Table 12 the results for Low band are given.
For each distortion scenario there is a min and a max value given. This variation is caused by a phase shifter
connected between switch and duplexer. In the test set-up the phase shifter represents a no ideal matching of
the switch to 50 Ohm.
Load
-20dB
-3dB
Tx
K&L
Mini Circuits
(ZHL-30W-252 -S+)
Signal
Generator
Power
Amplifier
Duplexer
Tunable
Bandpass
Filter
Circulator
DUT
ANT
Phase Shifter /
Delay Line
TRx
-20dB
ANT
K&L
Tunable
Bandpass Filter
Signal
Generator
Rx
K& L
Signal
Analyzer
Figure 14
Power reference plane
PTx = +20 dBm
PBl = -15 dBm
-3 dB
Tunable
Bandpass
Filter
Test set-up for IMD Measurements
Application Note AN302, Rev. 1.0
18 / 27
2012-11-29
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Broadband Diffential Diversity Applications
List of Content, Figures and Tables
5.3
Measurement results
Table 11
IMD products of Band I
IMD Band 1
1P  2P
1N  2N
1P  3P
1N  3N
Min
Max
Min
Max
Min
Max
Min
Max
IMD2Low
(fblocker = 190 MHz)
-116.72
-109.12
-117.71
-109.40
-118.60
-110.42
-118.89
-111.11
IMD2High
(fblocker = 4090 MHz)
-118.37
-114.48
-115.80
-113.08
-118.23
-115.11
-119.19
-115.91
IMD3
(fblocker = 1760 MHz)
-123.37
-117.75
-123.00
-117.54
-122.55
-117.68
-123.19
-116.54
Table 12
IMD products of Band V
IMD Band 5
1P  2P
1N  2N
1P  3P
1N  3N
Min
Max
Min
Max
Min
Max
Min
Max
IMD2Low
(fblocker = 45 MHz)
-107.69
-96.55
-108.80
-97.42
-108.59
-97.75
-107.62
-96.32
IMD2High
(fblocker = 1718 MHz)
-113.11
-108.38
-112.34
-109.11
-112.65
-108.11
-113.55
-109.56
IMD3
(fblocker = 791.5 MHz)
-112.88
-108.46
-111.70
-107.97
112.86
-108.50
-113.62
-108.74
Application Note AN302, Rev. 1.0
19 / 27
2012-11-29
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Broadband Diffential Diversity Applications
List of Content, Figures and Tables
6
Harmonic Generation
6.1
Measurement setup
Harmonic generation is another important parameter for the characterization of a RF switch. RF switches have
in such a Differential Band select Switching application to deal with high RF levels, up to 24 dBm. With this high
RF power at the input of the switch harmonics are generated. This harmonics (2
nd
rd
and 3 ) can disturb the other
reception bands or cause distortion in other RF applications (GPS, WLan) within the mobile phone.
Load
-20dB
Directional
Coupler
-20dB
Signal
Generator
Power
Amplifier
Circulator
Tunable
Bandpass
Filter
A
Power meter
Agilent
E4419B
-3dB
B
DUT
ANT
K&L
Signal
Analyzer
Figure 15
-20dB
Tunable
Bandstop
Filter
Tx
Directional
Coupler
Set-up for harmonics measurement
nd
rd
The results for the harmonic generation at 830 MHZ are shown in Figure 16 (2 harmonic) and Figure 17 (3
harmonic) for all RF ports.
At the x-axis the input power is plotted and at the y- axis the generated harmonics in dBm.
Application Note AN302, Rev. 1.0
20 / 27
2012-11-29
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Broadband Diffential Diversity Applications
List of Content, Figures and Tables
6.2
Measurement results
6.2.1
Low Band (824 MHz)
H2 of BGS22WL10
-40
15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
-45
[email protected]
-50
[email protected]
-55
H2 (dBm)
-60
[email protected]
-65
[email protected]
-70
-75
Pin (dBm)
-80
Figure 16
nd
2
harmonic at fc=824 MHz
H3 of BGS22WL10
-40
15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
-45
[email protected]
-50
-55
[email protected]
-60
-65
[email protected]
H3 (dBm)
-70
[email protected]
-75
-80
-85
-90
Pin (dBm)
Figure 17
rd
3 harmonic at fc=824 MHz
Application Note AN302, Rev. 1.0
21 / 27
2012-11-29
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6.2.2
High Band (1800 MHz)
H2 of BGS22WL10
-55
15
16
17
18
19
20
21
22
23
24
25
-60
H2 (dBm)
-65
1P to 2P @ 3V
1P to 3P @ 3V
-70
1N to 2N @ 3V
1N to 3N @ 3V
-75
-80
-85
Figure 18
nd
2
Pin (dBm)
harmonic at fc=1800 MHz
H3 of BGS22WL10
-45
15
16
17
18
19
20
21
22
23
24
25
-50
H3 (dBm)
-55
1P to 2P @ 3V
-60
1P to 3P @ 3V
-65
1N to 2N @ 3V
1N to 3N @ 3V
-70
-75
-80
Figure 19
Pin (dBm)
rd
3 harmonic at fc=1800 MHz
Application Note AN302, Rev. 1.0
22 / 27
2012-11-29
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Broadband Diffential Diversity Applications
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7
Power Compression Measurements
To judge the large signal capability the power compression is a usual measurement tool. The input power is
increase and at the output the power is measured. At a certain point the output power could not follow the input
and the switch compresses the RF signal. In the diagram below (Figure 20) the IL is plotted versus the injected
input power. The input power can be increased to 29 dBm and there is no compression visible of the RF port.
BGS22WL10
1.2
1
Loss (dB)
0.8
0.6
0.4
0.2
6.0
7.0
8.0
9.0
10.0
11.0
12.0
13.0
14.0
15.0
16.0
17.0
18.0
19.0
20.0
21.0
22.0
23.0
24.0
25.0
26.0
27.0
28.0
29.0
30.0
31.0
32.0
33.0
34.0
35.0
0
Pin (dBm)
Figure 20
Power Compression Measurement Results at fc=824 MHz
The measurements are done on Large Signal measurement setup which is not calibrated for Insertion Loss with
high precision. So the values here may differ with the actual IL values earlier in this report.
Application Note AN302, Rev. 1.0
23 / 27
2012-11-29
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8
Application Board and Measurement desciption
8.1
Application board
Figure 21
BGS22WL10 application board
Figure 22
Layout of the application board and deembedding kit
Vias
Rodgers , 0.2mm
Copper
35µm
Figure 23
FR4, 0.8mm
PCB layer information
Application Note AN302, Rev. 1.0
24 / 27
2012-11-29
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List of Content, Figures and Tables
8.2
Measurement description and deembedding
Below is a picture of the evaluation board used for the measurements (Figure 22). The board is designed in the
way that all connecting 50 Ohm lines have the same length.
To get correct called “device level” measurement values for the insertion loss of the BGS22WL10 all influences
and losses of the evaluation board, lines and connectors have to be eliminated. Therefore a separate deembedding board, representing the line length is necessary.
After full port calibration of the network analyzer (NWA) a deembedding has to be done in severall steps:

Attach empty SMA connector (with cutted RF line, Figure 24) at any port of the measurements setup
and perform “open” port extension for that one. Turn port extensions on.

Connect the “half” de-embedding board (Figure 22, smallest board) between the the port where one of
the two RFin port (1P/1N) of the BGS22WL10 will be connected and the port with the maded port
extension, store this as a S-parameter (s2p) file.

Turn all port extention off.

Load the stored s-parameter file as de-embedding on all used NWA ports

Check insertion loss with the de-embedding through board (Figure 22 right upper board)
Figure 24
SMA connector for deembedding procedure
If the check of the deembedding shows an insertion loss of the through about +- 0.4 dB (depending on the
measurement setup accuracy, e.g. NWA) then the Device itself can be measured.
Application Note AN302, Rev. 1.0
25 / 27
2012-11-29
BGS22WL10
Broadband Diffential Diversity Applications
List of Content, Figures and Tables
Author
André Dewai, Application Engineer of the Business Unit “RF and Protection Devices”
Ralph Kuhn, Senior Staff Application Engineer of the Business Unit “RF and Protection Devices”
Application Note AN302, Rev. 1.0
26 / 27
2012-11-29