Infineon-AN306-AN-v01_00-EN

B GS F110 G N26
SP 10T An tenna S wi tc h Mo dul e wi th
G PI O I nte rface , 2 G S MT X Por ts fo r
mul ti - mod e GS M/ E D G E, WC D M A o r
LTE Ap pli cations
Mai n RF F ront end A pplic ati on s
Applic atio n N ote A N 306
Revision: Rev. 1.0
2014-11-28
RF and P r otecti on D evic es
Edition 2015-01-21
Published by
Infineon Technologies AG
81726 Munich, Germany
© 2015 Infineon Technologies AG
All Rights Reserved.
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BGSF110GN26
Antenna Switch Module with integrated GPIO interface
Application Note AN306
Revision History: 2014-11-28
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Previous Revision: Not applicable; this is 1 version
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Subjects (major changes since last revision)
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YUDEN™ of Taiyo Yuden Co. TEAKLITE™ of CEVA, Inc. TEKTRONIX™ of Tektronix Inc. TOKO™ of TOKO
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Last Trademarks Update 2014-07-17
Application Note AN306, Rev. 1.0
3 / 23
2014-11-28
BGSF110GN26
Antenna Switch Module with integrated GPIO interface
List of Content, Figures and Tables
Table of Contents
1
Introduction ........................................................................................................................................ 6
2
2.1
2.2
2.3
2.4
BGSF110GN26 Features .................................................................................................................... 6
Main Features ...................................................................................................................................... 6
Functional Diagram .............................................................................................................................. 6
Pin Configuration .................................................................................................................................. 7
Pin Description ..................................................................................................................................... 7
3
3.1
Application .......................................................................................................................................... 8
Application Board ................................................................................................................................. 9
4
4.1
4.2
4.3
4.4
4.5
Small-Signal Characteristics ........................................................................................................... 10
Insertion Loss from Antenna Port to Respective RF Ports ................................................................ 10
Forward transmission GSM Tx........................................................................................................... 11
Reflection Antenna Port to all Ports ................................................................................................... 13
Port Reflection GSM Tx Ports ............................................................................................................ 14
Isolation .............................................................................................................................................. 15
5
5.1
5.1.1
5.1.2
5.1.3
Non-Linear Performance of BGSF110GN26 .................................................................................. 16
Intermodulation................................................................................................................................... 16
Intermodulation Measurement Setup ................................................................................................. 17
Intermodulation Measurement conditions .......................................................................................... 18
IMD Test Results for Band 1 and 5 .................................................................................................... 18
6
6.1.1
Harmonic Distortion ......................................................................................................................... 19
Harmonic Generation Measurement conditions ................................................................................. 19
7
Abbreviations ................................................................................................................................... 21
8
Authors .............................................................................................................................................. 22
Application Note AN306, Rev. 1.0
4 / 23
2014-11-28
BGSF110GN26
Antenna Switch Module with integrated GPIO interface
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
BGSF110GN26 functional diagram..................................................................................................... 6
BGSF110GN26 pin configuration ......................................................................................................... 7
BGSF110GN26 in a mobile phone front end ....................................................................................... 8
Layout of the application board ............................................................................................................ 9
Layout of de-embedding “ through” and “half” boards ......................................................................... 9
PCB layer information ........................................................................................................................ 10
Application circuit ............................................................................................................................... 10
Forward transmission antenna port to TRx ports ............................................................................... 11
Forward transmission GSM Tx ports.................................................................................................. 12
Forward transmission TRx2 over temperature ................................................................................... 12
Reflection antenna port to all TRx ports ............................................................................................ 13
Port reflection GSM Tx ports .............................................................................................................. 14
Isolation neighbour ports .................................................................................................................... 15
Isolation TRx to TX1 port ................................................................................................................... 15
Isolation TRx to Rx2 port .................................................................................................................... 16
Block diagram of RF switch intermodulation ...................................................................................... 17
Intermodulation measurement test setup ........................................................................................... 17
Set-up for harmonics measurement ................................................................................................... 19
Harmonics at fin=824 MHz .................................................................................................................. 20
Harmonics at fin=1710MHz ................................................................................................................. 20
List of Tables
Table 1
Table 2
Table 3
Table 4
Table 5
Table 6
Table 7
Table 8
Pin description (top view) ..................................................................................................................... 7
Insertion loss from antenna port to RF ports (all other ports terminated with 50Ohm resistance) .. 10
Insertion loss from antenna port to GSM Tx ports (all other ports terminated with 50 Ohm
resistance) .......................................................................................................................................... 11
Return loss from antenna port to RF ports (all other ports terminated with 50Ohm resistance) ....... 13
Return loss from antenna port to GSM Tx ports (all other ports terminated with 50-Ohm resistance)14
Test conditions of IMD measurements............................................................................................... 18
IMD measurements ............................................................................................................................ 18
Harmonic generation measurement conditions ................................................................................. 19
Application Note AN306, Rev. 1.0
5 / 23
2014-11-28
BGSF110GN26
Antenna Switch Module with integrated GPIO interface
Introduction
Introduction
1
The BGSF110GN26 is a Single-Pole Ten-Throw (SP10T) Antenna Switch Module (ASM) optimized for mobile
phone and wireless applications for operating frequencies up to 3.8 GHz. It is a perfect solution for multi-mode
handsets based on quadband GSM, WCDMA and LTE. The switch module configuration is shown in Figure 1
and supports a wide supply voltage range of 2.4 to 3.3 V.
The module comes in a miniature TSNP package and is comprised of a high power CMOS SP10T switch, an
integrated GPIO controller, and harmonic filters for GSM low-band and high-band transmit paths. The on-chip
controller integrates CMOS logic and level shifters, driven by control inputs from 1.35 to 3.1 V. External DC
blocking capacitors are not required in typical applications provided that DC voltages are not applied to any RF
port.
2
BGSF110GN26 Features
2.1
Main Features
•
•
•
•
•
•
•
•
•
•
Suitable for multi-mode GSM / EDGE / WCDMA / LTE / LTE-Advanced applications
Frequency range of 100 MHz to 2.7 GHz
Ultra-low insertion loss
Integrated GSM transmit filters
8 interchangeable, high-linearity WCDMA TRX ports
2 high-linearity GSM TX paths
High port-to-port isolation
Integrated MIPI RFFE interface
No DC decoupling capacitors required, if no DC applied on RF lines
Small form factor: 3.2 mm x 2.8 mm x 0.73 mm
2.2
Functional Diagram
ANT
TRX1
TRX2
TX_HB
TRX3
TRX4
Harmonic
Filters
TRX5
TRX6
TX_LB
TRX7
TRX8
SP10T
GND
VDD
V4
V3
V2
V1
GPIO
Controller
BGSF110G_Functional_Diagram.vsd
Figure 1
BGSF110GN26 functional diagram
Application Note AN306, Rev. 1.0
6 / 23
2014-11-28
BGSF110GN26
Antenna Switch Module with integrated GPIO interface
BGSF110GN26 Features
2.3
Pin Configuration
GND
TRX3
TRX2
TRX1
TRX7
GND
TRX8
21
GND
14
VDD
TX1
V4
GND
PG-TSNP-26-2
3.4 x 2.6 mm
400 µm pad pitch
V3
GND
V2
V1
TX2
26
GND
8
1
GND
TRX4
TRX5
TRX6
Figure 2
BGSF110GN26 pin configuration
2.4
Pin Description
Table 1
GND
GND
ANT
GND
Pin description (top view)
Pin NO
Name
Pin Type
Function
0
1
GND
GND
2
TRX4
GND
GND
I/O
Ground, die pad
DC ground
WCDMA TRX port
3
TRX5
I/O
WCDMA TRX port
4
5
TRX6
GND
GND
I/O
WCDMA TRX port
GND
GND
RF ground
RF ground
8
ANT
GND
I/O
GND
Antenna port
RF ground
9
GND
GND
RF ground
6
7
10
TX2
I
GSM HB port
11
GND
GND
GND
GND
RF ground
RF ground
TX1
GND
I
GND
I/O
GSM LB port
RF ground
12
13
14
15
16
TRX8
GND
17
TRX7
GND
I/O
18
TRX1
I/O
19
TRX2
I/O
WCDMA TRX port
WCDMA TRX port
20
TRX3
I/O
WCDMA TRX port
Application Note AN306, Rev. 1.0
7 / 23
WCDMA TRX port
RF ground
WCDMA TRX port
2014-11-28
BGSF110GN26
Antenna Switch Module with integrated GPIO interface
Application
Table 1
Pin description (top view)
Pin NO
Name
Pin Type
Function
21
GND
GND
DC ground
22
VDD
PWR
Supply Voltage
23
V4
I
GPIO Control pin
24
V3
I
GPIO Control pin
25
V2
I
GPIO Control pin
26
V1
I
GPIO Control pin
Application
3
A typical use of the BGSF110GN26 ASM in a mobile-phone application is shown in Figure 3. In the main
antenna path of the RF front end, the Infineon BGSF110GN26 routes the antenna signal to the required banddependent front end components (e.g. duplexers, filters, PA), which in turn are connected directly to the
transceiver IC. For the diversity path, Infineon recommends its RF switches such as the BGS15AN16. Infineon
also offers a broad portfolio of Low-Noise Amplifiers (LNAs) that are optimized for the receive path in mobilephone applications.
Infineon ASM
BGSF110GN26
Main
Infineon RF Switch
Diversity
ASM
Infineon
LNAs
BGAxx
Transceiver
Figure 3
BGSF110GN26 in a mobile phone front end
Application Note AN306, Rev. 1.0
8 / 23
2014-11-28
BGSF110GN26
Antenna Switch Module with integrated GPIO interface
Application
3.1
Application Board
Shown below is a picture of the EValuation Board (EVB) used for all measurements (Figure 4). This EVB is
designed such that all 50-Ohm connecting lines have the same length.
In order to obtain accurate values for insertion loss measurements of the BGSF110GN26, all influences and
losses of the EVB, lines, and connectors have to be eliminated. Therefore a separate de-embedding board
representing the line length is necessary (Figure 5).
The calibration of the NetWork Analyser (NWA) is done in six steps:
1) Perform full calibration on all NWA ports.
2) Attach special SMA connector (use same as soldered to EVB with no inner conductor) to port 2 and
perform “open” port extension. Turn the port extensions on.
3) Connect the “half” de-embedding board (Figure 5 right board) between port 1 and port 2, and store
this as an s-parameter (.s2p) file. Now turn all port extensions off.
4) Load the stored s-parameter file of the “half” de-embedding board as the de-embedding file for all
NWA ports used.
5) Now switch all port extentions on.
6) Cross-check the insertion loss with the “through” de-embedding board (Figure 5 left board)
Please note: On PCB, TRx7 is Rx 1 and TRx 8 is Rx2
Figure 4
Layout of the application board
Figure 5
Layout of de-embedding “ through” and “half” boards
The EVB is made of a sandwich of FR4 and Rogers 04002, and has 3 layers. The layer stack is shown in Figure
6.
Application Note AN306, Rev. 1.0
9 / 23
2014-11-28
BGSF110GN26
Antenna Switch Module with integrated GPIO interface
Small-Signal Characteristics
Vias
Rogers04002 , 0.2mm
Copper
35µm
FR4, 0.7mm
Figure 6
PCB layer information
4
Small-Signal Characteristics
The small-signal characteristics were measured at 25 °C using a Vector Network Analyzer (VNA), a supply
voltage, Vdd, of 3.0 V, and the application circuit shown in Figure 7.
ANT
BGS18MN14
SP8T
27nH
Figure 7
Application circuit
4.1
Insertion Loss from Antenna Port to Respective RF Ports
Table 2
Frequency
(MHz)
Insertion loss from antenna port to RF ports (all other ports terminated with 50Ohm
resistance)
704
716
740
751
824
881
TRx1
0.62
0.62
0.61
TRx2
0.63
0.62
TRx3
0.65
TRx4
0.61
0.6
0.6
0.59
0.6
0.69
0.71 0.73
0.73 0.75
0.79
0.8
0.89
1
1.1
1.7
0.62
0.62
0.6
0.6
0.6
0.6
0.68
0.7
0.72
0.72 0.74
0.77 0.78
0.85
0.99
1.1
1.7
0.64
0.64
0.64
0.61
0.61 0.61
0.61 0.67
0.68
0.7
0.7
0.71
0.75 0.76
0.83
0.97
1
1.6
0.63
0.62
0.62
0.62
0.6
0.6
0.6
0.7
0.72
0.72 0.73
0.77 0.78
0.86
1
1.1
1.8
TRx5
0.62
0.61
0.61
0.61
0.61
0.62 0.62
0.62 0.74
0.75 0.76
0.76 0.77
0.81 0.82
0.9
1.1
1.2
2
TRx6
0.59
0.59
0.58
0.58
0.57
0.57 0.57
0.57 0.72
0.75 0.79
0.79 0.82
0.88
1
1.3
1.4
2.3
TRx7 (Rx1)
0.62
0.61
0.61
0.61
0.6
0.61 0.61
0.61 0.73
0.74 0.75
0.75 0.76
0.79 0.79
0.85
0.98
1
1.7
TRx8 (Rx2)
0.63
0.62
0.62
0.62
0.59
0.59 0.59
0.59 0.72
0.71 0.71
0.71 0.72
0.75 0.76
0.84
0.98
1
1.6
Application Note AN306, Rev. 1.0
915
0.6
942
1710 1842 1960 1970 2017 2140 2170 2350 2593 2690 3500
0.68
10 / 23
0.9
2014-11-28
BGSF110GN26
Antenna Switch Module with integrated GPIO interface
Small-Signal Characteristics
Forward Transmission TRx ports
0
Forward Transmission (dB)
0.704 GHz
-0.5907 dB
2.14 GHz
-0.7452 dB
-0.5
-1
2.14 GHz
-0.8789 dB
3.5 GHz
-1.553 dB
-1.5
-2
-2.5
DB(|S(2,1)|)
TRX1
DB(|S(2,1)|)
TRX4
DB(|S(2,1)|)
RX1
DB(|S(2,1)|)
TRX2
DB(|S(2,1)|)
TRX5
DB(|S(2,1)|)
RX2
DB(|S(2,1)|)
TRX3
DB(|S(2,1)|)
TRX6
3.5 GHz
-2.34 dB
-3
0
1
2
Frequency (GHz)
Figure 8
Forward transmission antenna port to TRx ports
4.2
Forward transmission GSM Tx
Table 3
Frequency
(MHz)
Tx1(LB)
Tx2(HB)
3
4
Insertion loss from antenna port to GSM Tx ports (all other ports terminated with 50 Ohm
resistance)
704
716
0.69 0.69
1
1
740
751
0.71 0.71
1
824
881
915
0.75
0.79
0.81 0.82
1.1
1.2
1.3
1.3
1.4
1.9
2.1
4
8.5
11
47
1
0.97
0.96 0.97
43
31
28
28
28
28
28
30
36
41
25
1
Application Note AN306, Rev. 1.0
942
1710 1842 1960 1970 2017 2140 2170 2350 2593 2690 3500
11 / 23
2014-11-28
BGSF110GN26
Antenna Switch Module with integrated GPIO interface
Small-Signal Characteristics
Forward Transmission Tx ports
0
Forward Transmission (dB)
HB
-10
LB
1.862 GHz
-1.193 dB
0.883 GHz
-0.7937 dB
-20
-30
-40
1.714 GHz
-43.18 dB
-50
2.729 GHz
-42.78 dB
-60
0.0003
3.476 GHz
-50.61 dB
2
4
6
Frequency (GHz)
Figure 9
Forward transmission GSM Tx ports
0
TRx2 , -20 °
-0.2
TRx2, 25°
Forward Transmission
-0.4
TRx2, 85 °
-0.6
-0.8
-1
-1.2
500
1000
1500
2000
2500
3000
Frequency
Figure 10
Forward transmission TRx2 over temperature
Application Note AN306, Rev. 1.0
12 / 23
2014-11-28
BGSF110GN26
Antenna Switch Module with integrated GPIO interface
Small-Signal Characteristics
4.3
Reflection Antenna Port to all Ports
Table 4
Frequency
(MHz)
Return loss from antenna port to RF ports (all other ports terminated with 50Ohm
resistance)
704
716
740
751
824
881
TRx1
17.3
17.4
17.7
17.7
18.4
18.7 18.8
18.9 20.2
20.5 20.3
20.3 20.1
19.4 19.1
17.5
15
TRx2
17.3
17.4
17.6
17.7
18.4
18.7 18.8
18.8 19.8
20.1 20.1
20.1
19.5 19.4
18.1
15.7
14.6 10.3
TRx3
16.9
17.1
17.4
17.5
18.4
19.4
22.1 21.7
21.7 21.3
20.2 19.9
17.8
15.1
14.1 10.2
TRx4
17.5
17.7
18
18.1
18.9
19.4 19.6
19.7 20.7
20.8 20.4
20.4 20.1
19.1 18.8
17
14.6
13.5
TRx5
17.9
17.9
18
18
18.1
17.9 17.8
17.7 17.5
18.1 18.5
18.5 18.6
18.4 18.3
17.2
14.6
13.4 8.24
TRx6
18.9
19.1
19.5
19.6
20.4
20.7 20.7
20.8
17.3 16.4
16.4
16
14.9 14.7
13.1
11.1
10.4 7.05
TRx7 (Rx1)
17.5
17.6
17.8
17.8
18
18
18.1 18.1
17.9
16.6
15.5 10.2
TRx8 (Rx2)
17
17.2
17.5
17.6
18.6
20.1 19.8
17.7
15.2
14.3 10.8
19
18
915
19.2
942
1710 1842 1960 1970 2017 2140 2170 2350 2593 2690 3500
22
18
20
17.9
17.9 17.1
17.5 17.8
17.9
19.3 19.5
19.8 22.2
22.4 21.9
21.8 21.5
14
10.3
9
Reflection TR ports
0
Reflection (dB)
-5
-10
-15
-20
-25
-30
0.0003
TRx1
TRx4
DB(|S(1,1)|)
RX1
TRx2
TRx5
DB(|S(1,1)|)
RX2
TRx3
Trx6
2
4
6
Frequency (GHz)
Figure 11
Reflection antenna port to all TRx ports
Application Note AN306, Rev. 1.0
13 / 23
2014-11-28
BGSF110GN26
Antenna Switch Module with integrated GPIO interface
Small-Signal Characteristics
4.4
Port Reflection GSM Tx Ports
Table 5
Return loss from antenna port to GSM Tx ports (all other ports terminated with 50-Ohm
resistance)
Frequency (MHz)
704
716
740
751
824
881
915
942
Tx1 (LB)
11.0
11.1
11.2
11.4
12.9
15.4
18.4
22.4
Tx2 (HB)
18.2
18.0
17.6
17.4
16.1
15.2
14.9
14.7
1710
13.1
1842
12.9
1960
1970
11.7
11.6
2017
10.8
Reflection TX ports
0
Reflection (dB)
-10
HB
LB
-20
1.899 GHz
-16.15 dB
-30
-40
0.0003
2
4
6
Frequency (GHz)
Figure 12
Port reflection GSM Tx ports
Application Note AN306, Rev. 1.0
14 / 23
2014-11-28
BGSF110GN26
Antenna Switch Module with integrated GPIO interface
Small-Signal Characteristics
4.5
Isolation
Isolation_Neighbour_ TRx
0
-20
-40
-60
-80
-100
-120
0.0003
DB(|S(2,1)|)
Isolation_RX1_tRX2
DB(|S(2,1)|)
Isolation_TRX3_tTRX4
DB(|S(2,1)|)
Isolation_TRX1_tTRX2
DB(|S(2,1)|)
Isolation_TRX5_tTRX4
DB(|S(2,1)|)
Isolation_TRX3_tTRX2
DB(|S(2,1)|)
Isolation_TRX5_tTRX6
3
6
8.5
Frequency (GHz)
Figure 13
Isolation neighbour ports
Isolation TRx_to_Tx1
-20
-40
-60
-80
-100
-120
0.0003
DB(|S(2,1)|)
Isolatio_RX2_tTX1
DB(|S(2,1)|)
Isolation_TRX2_tTX1
DB(|S(2,1)|)
Isolation_RX1_tTX1
DB(|S(2,1)|)
Isolation_TRX3_tTX1
DB(|S(2,1)|)
Isolation_sTRX6_tTX1
DB(|S(2,1)|)
Isolation_TRX4_tTX1
DB(|S(2,1)|)
Isolation_TRX1_tTX1
DB(|S(2,1)|)
Isolation_TRX5_tTX1
2
4
6
Frequency (GHz)
Figure 14
Isolation TRx to TX1 port
Application Note AN306, Rev. 1.0
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2014-11-28
BGSF110GN26
Antenna Switch Module with integrated GPIO interface
Non-Linear Performance of BGSF110GN26
Isolation_TRx_to_Tx2
-20
-40
-60
-80
-100
DB(|S(2,1)|)
Isolation_RX1_tTX2
DB(|S(2,1)|)
Isolation_TRX1_tTX2
DB(|S(2,1)|)
Isolation_RX2_tTX2
DB(|S(2,1)|)
Isolation_TRX2_tTX2
DB(|S(2,1)|)
Isolation_sTRX5_tTX2
DB(|S(2,1)|)
Isolation_TRX3_tTX2
DB(|S(2,1)|)
Isolation_sTRX6_tTX2
DB(|S(2,1)|)
Isolation_TRX4_tTX2
-120
0.0003
2
4
6
Frequency (GHz)
Figure 15
Isolation TRx to Rx2 port
5
Non-Linear Performance of BGSF110GN26
Smart phones today can operate across several cellular bands covering GSM / EDGE / CDMA / UMTS /
WCDMA / LTE/TD-SCDMA / TD-LTE / LTE-A. The design of the RF front-end part in modern cellular phones is
becoming increasingly complex and demanding due to the increasing number of frequency bands and modes
that the phone needs to support. One of the main components of the RF front-end is the antenna switch that
selects which transmitter (TX)/receiver (RX) path can be connected to the antenna. The RF switch has to satisfy
high linearity requirements. The following material describes some of the main challenges of antenna switches
in mobile applications.
Modern smartphones are multi-mode devices that are capable of connecting to 2G, 3G and 4G networks. These
networks often use different frequency bands. The smartphone’s RF frontend must therefore include bandspecific components. In order to appropriately route signals for a given mode and band of operation, a highperformance RF switch is an essential component of the front-end circuitry. The performance requirements of
the RF swtich are discussed in the following sections.
5.1
Intermodulation
Intermodulation Distortion (IMD2 and IMD3) is a parameter that describes the linearty of a device under multitone conditions. The intermodulation between different frequency components generates undesired output
frequencies at the sum and difference frequencies of the input tones, and at multiples of those sum and
difference frequencies.
Application Note AN306, Rev. 1.0
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2014-11-28
BGSF110GN26
Antenna Switch Module with integrated GPIO interface
Non-Linear Performance of BGSF110GN26
Some of these possible intermodulation scenarios are shown in Figure 16. In this example, the transmitted (Tx)
signal from the main antenna is coupled into the diversity antenna with high power. This signal (20 dBm) and a
received jammer signal (-15 dBm) are entering the switch.
Certain combinations of the TX and jammer frequencies are producing second- and third-order intermodulation
products that fall into the desired reception band, and reduce the sensitivity of the receiver.
Main
BT
WLAN
Navigation
Wifi
FM
diversity
PA
CB
Radio
TV
...
PA
PA
Rx1
Tx1
Txn
Rxn
Rx1
Figure 16
Block diagram of RF switch intermodulation
5.1.1
Intermodulation Measurement Setup
Rxn
Rx2/3
Load
-20dB
-6 dB
IMD Product
reference Plane
Tx
Signal
Generator
Power
Amplifier
Circulator
Blocker
Signal
Duplexer
Tunable
Bandpass
Filter
-3 dB
ANT
Phase Shifter /
Delay Line
DUT
Tx
-6dB*
-20dB
ANT
Tunable
Bandpass
Filter
Signal
Generator
Rx
Signal
Analyzer
Figure 17
-6 dB
Power reference plane
regarding Specification
Intermodulation measurement test setup
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2014-11-28
BGSF110GN26
Antenna Switch Module with integrated GPIO interface
Non-Linear Performance of BGSF110GN26
A requirement of the test setup for IMD measurements is high isolation between the RX and TX signals (Figure
17). In practice, a laboratory-grade duplexer with an isolation of 80 dB is used.
Table 6 shows the test specification for Band 1 and Band 5.
5.1.2
Intermodulation Measurement conditions
Table 6
Test conditions of IMD measurements
Band 1
TX
Test case
FIN (MHz)
PIN (dBm) CW
IMD3
IMD2 low
IMD2 high
1950
20
Interferer
FIN (MHz)
PIN (dBm) CW
1760
190
-15
4090
IMD product
FIMD (MHz)
2140
Band 5
Test case
FIN (MHz)
PIN (dBm) CW
IMD3
IMD2 low
IMD2 high
835
20
FIN (MHz)
790
45
1715
PIN (dBm) CW
FIMD (MHz)
-15
880
The results for Band 1 and Band 5 are given in Table 7.
5.1.3
IMD Test Results for Band 1 and 5
Table 7
IMD measurements
Band 1
TX
Intermodulation Products UMTS
Band 1
Interferer
Test case
FIN (MHz)
PIN (dBm)
FIN (MHz)
PIN (dBm)
FIMD (MHz)
PIMD (dBm)
IIPx (dBm)
IMD3
IMD2 low
IMD2 high
1950
1950
1950
20
20
20
1760
190
4090
-15
-15
-15
2140
2140
2140
-107
-93
-104
66
98
109
TX
Band 5
Interferer
Intermodulation Products UMTS
Band 5
Test case
FIN (MHz)
PIN (dBm)
FIN (MHz)
PIN (dBm)
FIMD (MHz)
PIMD (dBm)
IIPx (dBm)
IMD3
835
20
790
-15
880
-123
74
IMD2 low
IMD2 high
835
835
20
20
45
1715
-15
-15
880
880
-92
-105
97
110
Application Note AN306, Rev. 1.0
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2014-11-28
BGSF110GN26
Antenna Switch Module with integrated GPIO interface
Harmonic Distortion
Harmonic Distortion
6
Harmonic distortion is another important parameter for the characterization of an RF switch. RF switches have
to withstand high RF levels, up to 36 dBm. This high RF power at the input of a switch generates harmonics of
the waveform that is present. These harmonics (2
nd
rd
and 3 ) can interfere with other reception bands or can
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
-20dB
Tunable
Bandstop
Filter
Signal
Analyzer
Directional
Coupler
Figure 18
Set-up for harmonics measurement
6.1.1
Harmonic Generation Measurement conditions
Table 8
Tx
Harmonic generation measurement conditions
Tx
FIN (MHz)
824
1800
Harmonic Products
FH2(MHz)
FH3 (MHz)
PIN (dBm), 50% DC
20…38 TX LB port
20…30 TRX LB ports
20…38 TX HB port
20…30 TRX HB ports
1648
2472
3600
5400
The results for the harmonic generation at 824 MHZ and 1710 MHz are shown in Figure 19 for TX1 and Figure
20 Tx2. The input power (Pin) is plotted on the x axis, and the generated harmonics in dBm on the y axis.
Application Note AN306, Rev. 1.0
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2014-11-28
BGSF110GN26
Antenna Switch Module with integrated GPIO interface
Harmonic Distortion
Harmicics [dBm]
Harmonic
HarmonicGeneration
Gereration @ 824 MHz TX1
0
-10
-20
-30
-40
-50
-60
-70
-80
-90
H2
H3
20
25
30
35
40
Pin [dBm]
Figure 19
Harmonics at fin=824 MHz
Harmonic
HarmonicGeneration
Gerneration@1710MHz Tx2
0
-10
Harmonics[dBm]
-20
-30
-40
-50
H2
-60
H3
-70
-80
-90
20
25
30
35
40
Pin [dBm]
Figure 20
Harmonics at fin=1710MHz
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2014-11-28
BGSF110GN26
Antenna Switch Module with integrated GPIO interface
Abbreviations
7
ASM
CMOS
EDGE
FR4
GPIO
GPS
GSM
LTE
LTE-A
PA
PCB
SMA
Rodgers
RF
TD LTE
TD-SCDMA
TSNP
UMTS
W-CDMA
WLAN
Abbreviations
Antenna Switch Module
Complementary Metall-Oxide-Semiconductor
Enhanced Data Rates for GMS Evolution
Material for PCB
General Purpose Input Output
Global Positioning System
Global System for Mobile Communication
Long-Term Evolution
LTE Advanced
Power Amplifier
Printed Circuit Board
Sub Miniature version A
Material for RF PCBs
Radio Frequency
Time Division LTE
Time Division Synchronous Code Division Multiple Access
Thin Small Non Leaded Package
Universal Mobile Telecommunications System
Wideband Code Division Multiple Access
Wireless Local Area Network
Application Note AN306, Rev. 1.0
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2014-11-28
BGSF110GN26
Antenna Switch Module with integrated GPIO interface
Authors
8
Authors
Andre Dewai, Senior Application Engineer of the Business Unit “RF and Protection Devices”
Ralph Kuhn, Senior Staff Application Engineer of the Business Unit “RF and Protection Devices”
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2014-11-28
w w w . i n f i n e o n . c o m
Published by Infineon Technologies AG
AN306