BGS16MN14 SP6T Antenna Switch Diversity RF Frontend

RF and Protect ion Devices

BGS16MN14

Appl icat ion Note AN368 Revision: Rev. 1.0

2014-05-23

SP6T Antenna Switch

Diversi ty RF Frontend Appl icat ions

Edition 2014-06-02

Published by Infineon Technologies AG 81726 Munich, Germany

© 2014 Infineon Technologies AG All Rights Reserved.

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Information

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BGS16MN14 Diversity RF Frontend Applications

Application Note AN368, Rev. 1.0 2014-05-23 3 / 20

Application Note AN368

Revision History: 2014-05-23

Previous Revision: prev. Rev. x.x

Page Subjects (major changes since last revision)

Trademarks of Infineon Technologies AG

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Other Trademarks

Advance Design System™ (ADS) of Agilent Technologies, AMBA™, ARM™, MULTI-ICE™, KEIL™, PRIMECELL™, REALVIEW™, THUMB™, µVision™ of ARM Limited, UK. AUTOSAR™ is licensed by AUTOSAR development partnership. Bluetooth™ of Bluetooth SIG Inc. CAT-iq™ of DECT Forum. COLOSSUS™, FirstGPS™ of Trimble Navigation Ltd. EMV™ of EMVCo, LLC (Visa Holdings Inc.). EPCOS™ of Epcos AG. FLEXGO™ of Microsoft Corporation. FlexRay™ is licensed by FlexRay Consortium. HYPERTERMINAL™ of Hilgraeve Incorporated. IEC™ of Commission Electrotechnique Internationale. IrDA™ of Infrared Data Association Corporation. ISO™ of INTERNATIONAL ORGANIZATION FOR STANDARDIZATION. MATLAB™ of MathWorks, Inc. MAXIM™ of Maxim Integrated Products, Inc. MICROTEC™, NUCLEUS™ of Mentor Graphics Corporation. MIPI™ of MIPI Alliance, Inc. MIPS™ of MIPS Technologies, Inc., USA. muRata™ of MURATA MANUFACTURING CO., MICROWAVE OFFICE™ (MWO) of Applied Wave Research Inc., OmniVision™ of OmniVision Technologies, Inc. Openwave™ Openwave Systems Inc. RED HAT™ Red Hat, Inc. RFMD™ RF Micro Devices, Inc. SIRIUS™ of Sirius Satellite Radio Inc. SOLARIS™ of Sun Microsystems, Inc. SPANSION™ of Spansion LLC Ltd. Symbian™ of Symbian Software Limited. TAIYO YUDEN™ of Taiyo Yuden Co. TEAKLITE™ of CEVA, Inc. TEKTRONIX™ of Tektronix Inc. TOKO™ of TOKO KABUSHIKI KAISHA TA. UNIX™ of X/Open Company Limited. VERILOG™, PALLADIUM™ of Cadence Design Systems, Inc. VLYNQ™ of Texas Instruments Incorporated. VXWORKS™, WIND RIVER™ of WIND RIVER SYSTEMS, INC. ZETEX™ of Diodes Zetex Limited.

Last Trademarks Update 2011-11-11


List of Content, Figures and Tables


Table of Content

1 Introduction ........................................................................................................................................ 6

2 BGS16MN14 Features ........................................................................................................................ 6 2.1 Main Features ...................................................................................................................................... 6 2.2 Functional Diagram .............................................................................................................................. 6 2.3 Pin Configuration .................................................................................................................................. 7 2.4 Pin Description ..................................................................................................................................... 7

3 Application .......................................................................................................................................... 8 3.1 Application Board ................................................................................................................................. 8

4 Small Signal Characteristics ........................................................................................................... 10 4.1 Insertion Loss from Antenna to the respective RF port...................................................................... 10 4.2 Return Loss from Antenna to the respective RF port ......................................................................... 10 4.3 Forward Transmission ........................................................................................................................ 11 4.4 Reflection Antenna Port ..................................................................................................................... 11 4.5 Port Reflection .................................................................................................................................... 12 4.6 Antenna Isolation Neighbour Ports .................................................................................................... 12 4.7 Port Isolation Neighbour Ports ........................................................................................................... 13

5 Intermodulation ................................................................................................................................ 14 5.1 Introduction ......................................................................................................................................... 14 5.2 IMD Test Set-up ................................................................................................................................. 14 5.3 IMD Test Results for Band 1 and 5 .................................................................................................... 15

6 Harmonic Generation ....................................................................................................................... 15

7 Appendix: Switch Controller Unit ................................................................................................... 18 7.1 Operating Guide ................................................................................................................................. 18

8 Authors .............................................................................................................................................. 19


List of Content, Figures and Tables


List of Figures

Figure 1 BGS16MN14 Functional Diagram ....................................................................................................... 6 Figure 2 BGS16MN14 Pin Configuration ........................................................................................................... 7 Figure 3 RF switch in mobile phone cellular frontend ........................................................................................ 8 Figure 4 Layout of the application board ............................................................................................................ 9 Figure 5 Layout of de-embedding boards .......................................................................................................... 9 Figure 6 PCB layer information .......................................................................................................................... 9 Figure 7 Application circuit ............................................................................................................................... 10 Figure 8 Forward Transmission Curves for RF Ports ....................................................................................... 11 Figure 9 Reflection Antenna Port ..................................................................................................................... 11 Figure 10 Port Reflection .................................................................................................................................... 12 Figure 11 Antenna Isolation Neighbour Ports .................................................................................................... 12 Figure 12 Port Isolation of Neighbour Ports ....................................................................................................... 13 Figure 13 Block diagram of RF Switch intermodulation ..................................................................................... 14 Figure 14 Test set-up for IMD Measurements .................................................................................................... 14 Figure 15 Set-up for harmonics measurement ................................................................................................... 15 Figure 16 2

nd Harmonic at fc=824 MHz............................................................................................................... 16

Figure 17 3rd

harmonic at fc=824 MHz ................................................................................................................ 16 Figure 18 2

nd Harmonic at fc=1800 MHz............................................................................................................. 17

Figure 19 3rd

Harmonic at fc=1800 MHz ............................................................................................................. 17 Figure 20 Switch Controller Unit Board .............................................................................................................. 18

List of Tables

Table 1 Pin Description (top view) .................................................................................................................... 7 Table 2 Insertion Loss from Antenna to the respective RF port with all other ports terminated with 50Ω ...... 10 Table 3 Antenna Return Loss with all other ports terminated with 50Ω .......................................................... 10 Table 4 IMD Measurements ............................................................................................................................ 15


Introduction


1 Introduction

The BGS16MN14 is a Single Pole Six Throw (SP6T) Diversity Switch optimized for wireless applications up to 2.7 GHz. It is a perfect solution for multi-mode handsets based on quadband GSM, WCDMA and LTE. The switch configuration is shown in Fig. 1. The BGS16MN14 comes in a miniature TSNP package and comprises of a high power CMOS SP6T switch with integrated MIPI RFFE interface.

No external DC blocking capacitors are required in typical applications as long as no DC is applied to any RF port.

2 BGS16MN14 Features

2.1 Main Features

Suitable for multi-mode EDGE / C2K / WCDMA / LTE applications

Ultra-low insertion loss and harmonics generation

6 high-linearity, interchangeable WCDMA RX ports

0.1 to 2.7 GHz coverage

High port-to-port-isolation

Direct to battery supply enabled by large supply voltage range

from 2.5 V to 5.5 V

Integrated MIPI RFFE interface supporting 1.2 and 1.8 V bus voltage

Software programmable MIPI RFFE USID

No decoupling capacitors required if no DC applied on RF lines

Small form factor 2.0 mm x 2.0 mm

1 kV HBM ESD protection

RoHS and WEEE compliant package

2.2 Functional Diagram

Figure 1 BGS16MN14 Functional Diagram

MIPI RFFE

Controller

SD

AT

A

SC

LK

VD

D

GN

D

VIO

ANT

RX01 RX02

RX03 RX04

RX05

SP6T

RX06


BGS16MN14 Features


2.3 Pin Configuration

Figure 2 BGS16MN14 Pin Configuration

2.4 Pin Description

Table 1 Pin Description (top view)

Pin NO Name Pin Type Function

0 GND GND RF ground; die pad

1 RX03 I/O RX port 3



4 VDD PWR VDDSupply Voltage

5 VIO PWR MIPI RFFE Supply

6 SDATA I/O MIPI RFFE data

7 SCLK I MIPI RFFE clock

8 NC Not connected




12 NC Not connected

13 ANT I/O Antenna port

14 NC Not connected

91011

SCLK

VIO

SDATAR

X0

4

12

13

8

14

7

6

5

4321

NC

NC

VD

DN

C

ANT

RX

05

RX

01

RX

02

RX

03

RX

06

0


Application


3 Application

A typical application of the BGS16MN14 RF switch in a mobile phone application is shown in Figure 3. In the diversity path of the RF frontend the BGS16MN14 switches the different receive bands to the inputs of the transceiver. Infineon offers also a broad portfolio of Low Noise Amplifiers and Antenna Switch Modules.

Figure 3 RF switch in mobile phone cellular frontend

3.1 Application Board

Below is a picture of the evaluation board used for the measurements (Figure 4). The board is designed so that all connecting 50 Ohm lines have the same length.

In order to get accurate values for the insertion loss of the BGS16MN14 all influences and losses of the evaluation board, 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 severall steps:

- Perform full calibration on all NWA ports.

- Attach empty SMA connector at port 2 and perform “open” port extension. Turn port extensions on.

Transceiver

ASM

Infineon ASMs BGSF18G BGSF110GN26

Infineon RF Switch BGS16MN14

Infineon LNAs BGAxx

http://www.infineon.com/dgdl?folderId=db3a30431f848401011fcbf2ab4c04c4&fileId=db3a30433f2e70c5013f334cfa28119c

http://www.infineon.com/dgdl?folderId=db3a30431f848401011fcbf2ab4c04c4&fileId=db3a30433ea3aef6013ea848e89e07b1

http://www.infineon.com/cms/en/product/rf-and-wireless-control/rf-switch/BGS16MN14/productType.html?productType=db3a30443fccdddd013fccdeaa440001

http://www.infineon.com/cms/en/product/rf-and-wireless-control/rf-mmic-lna/lte-lna-solutions/channel.html?channel=db3a304314dca389011540e1d03815ed


Application


- Connect the “half” de-embedding board (Figure 5 left board) between port1 and port2, store this as a

s-parameter (.s2p) file.

- Turn all port extentions off.

- Load the stored s-parameter file as de-embedding file for all used NWA ports

- Switch all port extentions on

- Check insertion loss with the de-embedding through board (Figure 5 right board)

Figure 4 Layout of the application board

Figure 5 Layout of de-embedding boards

The construction of the PCB is shown in Figure 6.

Figure 6 PCB layer information

Copper

35µm

Rodgers , 0.2mm

FR4, 0.7mm

Vias


Small Signal Characteristics


4 Small Signal Characteristics

The small signal characteristics are measured at 25 °C with a Network analyzer in an application circuit shown

in figure 7.

Figure 7 Application circuit

4.1 Insertion Loss from Antenna to the respective RF port

Table 2 Insertion Loss from Antenna to the respective RF port with all other ports terminated with 50Ω

Frequency (MHz)

740 751 881 942 1842 1960 2017 2140 2350 2593 3500

RX1 0.43 0.42 0.36 0.34 0.31 0.32 0.33 0.34 0.36 0.38 0.52

RX2 0.41 0.41 0.36 0.34 0.33 0.34 0.35 0.36 0.38 0.41 0.56

RX3 0.4 0.4 0.34 0.32 0.29 0.3 0.31 0.33 0.36 0.4 0.61

RX4 0.42 0.41 0.36 0.34 0.32 0.33 0.34 0.35 0.39 0.43 0.65

RX5 0.41 0.4 0.34 0.32 0.3 0.31 0.32 0.33 0.36 0.38 0.48

RX6 0.44 0.44 0.38 0.36 0.32 0.33 0.34 0.35 0.37 0.4 0.54

4.2 Return Loss from Antenna to the respective RF port

Table 3 Antenna Return Loss with all other ports terminated with 50Ω

Frequency (MHz)

740 751 881 942 1842 1960 2017 2140 2350 2593 3500

RX1 15 15.1 16.9 17.7 33.7 32.6 31.7 30.4 28.6 27 20.2

RX2 15.5 15.6 17.5 18.4 29.6 29.3 29 28.7 27.6 25.3 18.2

RX3 15.3 15.5 17.4 18.2 33.6 29.6 28 25.6 22.9 20.5 15.2

RX4 15.5 15.6 17.7 18.6 31.6 29 27.7 25.9 23.4 20.9 15.1

RX5 15 15.2 17.7 18.8 24.4 22.7 22.1 21.1 19.7 19.2 19.5

RX6 14.7 14.9 16.6 17.5 37.7 32.8 30.9 28.8 27.1 26.2 20.9

27nH

ANT

BGS16MN14SP6T




4.3 Forward Transmission

Figure 8 Forward Transmission Curves for RF Ports

4.4 Reflection Antenna Port

Figure 9 Reflection Antenna Port

0.5 1.5 2.5 3.5

Frequency (GHz)

BGS16MN14 Forward Transmission

-1

-0.75

-0.5

-0.25

0

Forw

ard

Tra

nsm

issio

n (

dB

)

2.59 GHz-0.38 dB

2.35 GHz-0.36 dB

3.50 GHz-0.48 dB

1.96 GHz-0.30 dB

2.14 GHz-0.33 dB

1.84 GHz-0.29 dB

0.94 GHz-0.32 dB

0.88 GHz-0.34 dB

0.75 GHz-0.40 dB

0.74 GHz-0.40 dB

ANT_Rx1

ANT_Rx2

ANT_Rx3

ANT_Rx4

ANT_Rx5

ANT_Rx6

0.5 1.5 2.5 3.5 4

Frequency (GHz)

BGS16MN14 Reflection Antenna Port

-60

-45

-30

-15

0

Reflection (

dB

)

2.69 GHz-19.4 dB

Rx1

Rx2

Rx3

Rx4

Rx5

Rx6




4.5 Port Reflection

Figure 10 Port Reflection

4.6 Antenna Isolation Neighbour Ports

Figure 11 Antenna Isolation Neighbour Ports

0.5 1.5 2.5 3.5 4

Frequency (GHz)

BGS16MN14 Reflection Rx Ports

-70

-55

-40

-25

-10

0

Reflection (

dB

)

2.69 GHz-16.95 dB

Rx1

Rx2

Rx3

Rx4

Rx5

Rx6

0.05 1.05 2.05 3.05 3.5

Frequency (GHz)

Antenna Isolation of Neighbour Ports

-100

-80

-60

-40

-20

0

Isola

tion (

dB

)

2.69 GHz-27.86 dB

Rx1 activeANT_Rx2

Rx1 activeANT_Rx6

Rx2 activeANT_Rx3

Rx2 activeANT_Rx1

Rx3 activeANT_Rx4

Rx3 activeANT_Rx2

Rx4 activeANT_Rx5

Rx4 activeANT_Rx3

Rx5 activeANT_Rx6

Rx5 activeANT_Rx4

Rx6 activeANT_Rx1

Rx6 activeANT_Rx5




4.7 Port Isolation Neighbour Ports

Figure 12 Port Isolation of Neighbour Ports

0.05 1.05 2.05 3.05 3.5

Frequency (GHz)

Port Isolation of Neighbour Ports

-100

-80

-60

-40

-20

0

Isola

tion (

dB

)

2.69 GHz-25.16 dB

Rx1 activeRx1_Rx2

Rx1 activeRx1_Rx6

Rx2 activeRx2 Rx3

Rx2 activeRx2_Rx1

Rx3 activeRx3_Rx4

Rx3 activeRx3_Rx2

Rx4 activeRx4_Rx5

Rx4 activeRx4_Rx3

Rx5 activeRx5_Rx6

Rx5 activeRx5_Rx4

Rx6 activeRx6_Rx1

Rx6 activeRx6_Rx5


Intermodulation


5 Intermodulation

5.1 Introduction

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.

Figure 13 Block diagram of RF Switch intermodulation

Special combinations of TX and Jammer signal are producing intermodulation products 2nd

and 3rd order, which

fall in the RX band and disturb the wanted RX signal.

5.2 IMD Test Set-up

The test setup for the IMD measurements has to provide a very high isolation between RX and TX signals.

( Figure 14).For the RX / TX separation a professional duplexer with 80 dB isolation is used.

Please find the results for high and low band in table 5 below. 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.

Figure 14 Test set-up for IMD Measurements

RF Switch

Diversity

Antenna

Receiver

Coupled Tx

Signal from

main antenna

Jammer

(CW)

IMD

Mini Circuits

(ZHL-30W-252 -S+)

Load

Signal Generator

Power Amplifier

Circulator

-20dB

Signal Analyzer

-3 dB

-3dB

Duplexer

Tx

Rx

ANTPhase Shifter /

Delay Line

Signal Generator

DUT -20dB

Tunable Bandpass Filter

K & L

Power reference planePTx = +20 dBm

PBl = -15 dBm

TRx ANT

K & L

Tunable Bandpass

Filter

K & L

Tunable

Bandpass Filter


Harmonic Generation


5.3 IMD Test Results for Band 1 and 5

Table 4 IMD Measurements

Band 1 TX Interferer

Intermodulation Products UMTS Band 1

Testcase FIN

(MHz) PIN (dBm) FIN (MHz) PIN (dBm) FIMD (MHz) PIMD (dBm) IIPx (dBm)

IMD3 1950 20 1760 -15 2140 -113 68

IMD2 low 1950 20 190 -15 2140 -94 99

IMD2 high 1950 20 4090 -15 2140 -111 116

Band 5 TX Interferer

Intermodulation Products UMTS Band 5

Testcase FIN

(MHz) PIN (dBm) FIN (MHz) PIN (dBm) FIMD (MHz) PIMD (dBm) IIPx (dBm)

IMD3 835 20 790 -15 880 -111 68

IMD2 low 835 20 45 -15 880 -99 105

IMD2 high 835 20 1715 -15 880 -110 115

6 Harmonic Generation

Harmonic generation is another important parameter for the characterization of a RF switch. RF switches have

to deal with high RF levels, up to 27 dBm. With this high RF power at the input of the switch harmonics are

generated. This harmonics (2nd

and 3rd

) can disturb the other reception bands or cause distortion in other RF

applications (GPS, WLan) within the mobile phone.

Figure 15 Set-up for harmonics measurement

Lo

ad

Signal

Generator

Power

AmplifierCirculator

Tunable

Bandpass

Filter

-20dB

Directional

Coupler

Directional

CouplerTunable

Bandstop

Filter

Signal

Analyzer

-3dB

K & L

Power meter

Agilent

E4419B

A

B

-20dB

-20dB

DUTTxANT


Harmonic Generation


The results for the harmonic generation at 830 MHZ are shown in Figure 16 (2nd

harmonic) and Figure 17 (3rd

harmonic) for all RF ports.

At the x-axis the input power is plotted and at the y- axis the generated harmonics in dBm.

Figure 16 2nd

Harmonic at fc=824 MHz

Figure 17 3rd

harmonic at fc=824 MHz

-90

-85

-80

-75

-70

-65

-60

-55

-50

20 21 22 23 24 25 26 27

H2

(d

Bm

)

Pin (dBm)

BGS16MN14 RX at fin=824MHz

RX1

RX2

RX3

RX4

RX5

RX6

-90

-85

-80

-75

-70

-65

-60

-55

-50

20 21 22 23 24 25 26 27

H3

(d

Bm

)

Pin (dBm)


RX1

RX2

RX3

RX4

RX5

RX6


Harmonic Generation


Figure 18 2nd


Figure 19 3rd


-90

-85

-80

-75

-70

-65

-60

-55

-50

20 21 22 23 24 25 26 27

H2

(d

Bm

)

Pin (dBm)


RX1

RX2

RX3

RX4

RX5

RX6

-100

-95

-90

-85

-80

-75

-70

-65

-60

-55

-50

20 21 22 23 24 25 26 27

H3

(d

Bm

)

Pin (dBm)


RX1

RX2

RX3

RX4

RX5

RX6


Appendix: Switch Controller Unit


7 Appendix: Switch Controller Unit

The BGS18MN14 is controlled via MIPI interface and Infineon offers a MIPIcontroller unit to ease the evaluation of its BGS18MN14 on application board. The unit is very simple to use with a few buttons to select the right device and different states.

This section helps as a short user guide for the controller unit shown in Figure 20. The controller unit requires a DC supply of 5.5V with a current capability of 50mA.

Figure 20 Switch Controller Unit Board

Please observe the following steps to use the controller unit:

7.1 Operating Guide

1. Connect evalboard and control unit via controller cable

2. Connect control unit to power supply

3. Version number “S.0” is displayed

4. Press P1 and P3 simultaneously until desired switch type is displayed

- “0D” for BGS110MN20



5. Press P1 or P3 to enable active mode “PU” is displayed*

6. Press P1 or P3 to alter switch state

- IS … Isolation Mode (all channels off)

- PD … Power Down Mode (low current consumption)

- PU ... Power Up Mode (active mode)

- R1 – R0 ... RX1 – RX10 enabled

P3

P2

P1

to BGSF18D

G V G

N C N

D C D

GND GND

GND GND

Vcc NC

LVdd SPI

FRM CLK


Authors


8 Authors

Ralph Kuhn, Senior Staff Application Engineer of the Business Unit “RF and Protection Devices”

Andre Dewai, Senior Application Engineer of the Business Unit “RF and Protection Devices”

w w w . i n f i n e o n . c o m

Published by Infineon Technologies AG AN368

Documents

BGS16MN14 SP6T Antenna Switch Diversity RF Frontend