Improving Immunity of BGA231L7 against Out-Of-Band Jammers (LTE Band-13, GSM850/900/1800, UMTS, WLAN) Using Series Notches Application Note AN276 Revision: Rev. 1.0 RF and Protection Devices
Edition 2011-09-16 Published by Infineon Technologies AG 81726 Munich, Germany 2011 Infineon Technologies AG All Rights Reserved. LEGAL DISCLAIMER THE INFORMATION GIVEN IN THIS APPLICATION NOTE IS GIVEN AS A HINT FOR THE IMPLEMENTATION OF THE INFINEON TECHNOLOGIES COMPONENT ONLY AND SHALL NOT BE REGARDED AS ANY DESCRIPTION OR WARRANTY OF A CERTAIN FUNCTIONALITY, CONDITION OR QUALITY OF THE INFINEON TECHNOLOGIES COMPONENT. THE RECIPIENT OF THIS APPLICATION NOTE MUST VERIFY ANY FUNCTION DESCRIBED HEREIN IN THE REAL APPLICATION. INFINEON TECHNOLOGIES HEREBY DISCLAIMS ANY AND ALL WARRANTIES AND LIABILITIES OF ANY KIND (INCLUDING WITHOUT LIMITATION WARRANTIES OF NON-INFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS OF ANY THIRD PARTY) WITH RESPECT TO ANY AND ALL INFORMATION GIVEN IN THIS APPLICATION NOTE. Information For further information on technology, delivery terms and conditions and prices, please contact the nearest Infineon Technologies Office (www.infineon.com). Warnings Due to technical requirements, components may contain dangerous substances. For information on the types in question, please contact the nearest Infineon Technologies Office. Infineon Technologies components may be used in life-support devices or systems only with the express written approval of Infineon Technologies, if a failure of such components can reasonably be expected to cause the failure of that life-support device or system or to affect the safety or effectiveness of that device or system. Life support devices or systems are intended to be implanted in the human body or to support and/or maintain and sustain and/or protect human life. If they fail, it is reasonable to assume that the health of the user or other persons may be endangered.
Application Note AN276 Revision History: Previous Revision: None Page Subjects (major changes since last revision) Trademarks of Infineon Technologies AG AURIX, C166, CanPAK, CIPOS, CIPURSE, EconoPACK, CoolMOS, CoolSET, CORECONTROL, CROSSAVE, DAVE, EasyPIM, EconoBRIDGE, EconoDUAL, EconoPIM, EiceDRIVER, eupec, FCOS, HITFET, HybridPACK, I²RF, ISOFACE, IsoPACK, MIPAQ, ModSTACK, my-d, NovalithIC, OptiMOS, ORIGA, PRIMARION, PrimePACK, PrimeSTACK, PRO-SIL, PROFET, RASIC, ReverSave, SatRIC, SIEGET, SINDRION, SIPMOS, SmartLEWIS, SOLID FLASH, TEMPFET, thinq!, TRENCHSTOP, TriCore. 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. Mifare of NXP. 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 2011-02-24 Application Note AN276, Rev. 1.0 3 / 22
Table of Content, List of Figures and Tables Table of Content 1 BGA231L7 GPS Front-End LNA... 6 2 Introduction... 7 3 Application Circuit... 9 4 Typical Measurement Results... 10 5 Measured Graphs for GPS and GLONASS bands... 12 6 Miscellaneous Measured Graphs... 17 7 Evaluation Board... 20 8 Authors... 21 Application Note AN276, Rev. 1.0 4 / 22
Table of Content, List of Figures and Tables List of Figures Figure 1 BGA231L7 in TSLP-7-1 Package (2 mm x 1.3 mm x 0.4 mm)... 6 Figure 2 Block diagram of the BGA231L7 for GNSS band 1559-1615MHz applications... 8 Figure 3 BGA231L7 application circuit for improved rejection of out-of-band jammers... 9 Figure 4 Power gain of BGA231L7 for GPS and GLONASS bands... 12 Figure 5 Narrowband power gain of BGA231L7 for GPS and GLONASS bands... 12 Figure 6 Input matching of BGA231L7 for GPS and GLONASS bands... 13 Figure 7 Output matching of BGA231L7 for GPS and GLONASS bands... 13 Figure 8 Reverse isolation of BGA231L7 for GPS and GLONASS bands... 14 Figure 9 Noise figure of BGA231L7 for GPS and GLONASS bands... 14 Figure 10 Input 1 db compression point of BGA231L7 at supply voltage of 1.8V for GPS and GLONASS Figure 11 bands... 15 Input 1 db compression point of BGA231L7 at supply voltage of 2.8V for GPS and GLONASS bands... 15 Figure 12 Carrier and intermodulation products of BGA231L7 for GPS band at Vcc=1.8V... 16 Figure 13 Carrier and intermodulation products of BGA231L7 for GPS band at Vcc=2.8V... 16 Figure 14 Stability factor k of BGA231L7 upto 10GHz... 17 Figure 15 Stability factor µ1 of BGA231L7 upto 10GHz... 17 Figure 16 Stability factor µ2 of BGA231L7 upto 10GHz... 18 Figure 17 Input and output matching for GPS and GLONASS bands with Vcc=1.8V... 18 Figure 18 Input and output matching for GPS and GLONASS bands with Vcc=2.8V... 19 Figure 19 Populated PCB picture of BGA231L7... 20 Figure 20 PCB layer stack... 20 List of Tables Table 1 Pin Definition... 8 Table 2 Switching Mode... 8 Table 3 Bill-of-Materials... 9 Table 4 Electrical Characteristics (at room temperature), Vcc = Vpon = 1.8V... 10 Table 5 Electrical Characteristics (at room temperature), Vcc = Vpon = 2.8V... 11 Application Note AN276, Rev. 1.0 5 / 22
BGA231L7 GPS Front-End LNA 1 BGA231L7 GPS Front-End LNA 1.1 Features High gain: 16.0 db High out-of-band input 3 rd -order intercept point: +5 dbm High input 1dB compression point: -5 dbm Low noise figure: 0.75 db Low current consumption: 4.4 ma Operating frequency: 1550-1615 MHz Supply voltage: 1.5 V to 3.6 V Digital on/off switch (1V logic high level) Tiny TSLP-7-1 leadless package B7HF Silicon Germanium technology RF output internally matched to 50 Ω Only three external SMD components necessary 2 kv HBM ESD protection (including AI-pin) Pb-free (RoHS compliant) package Figure 1 BGA231L7 in TSLP-7-1 Package (2 mm x 1.3 mm x 0.4 mm) 1.2 Applications - Global Positioning System (GPS) - GLONASS (Russian GNSS) - Galileo (European GNSS) - COMPASS (Chinese Beidou Navigation System) Application Note AN276, Rev. 1.0 6 / 22
Introduction 2 Introduction The BGA231L7 is a front-end Low Noise Amplifier (LNA) for Global Navigation Satellite Systems (GNSS) application. It is based on Infineon Technologies B7HF Silicon-Germanium technology, enabling a cost-effective solution in a small TSLP-7-1 package with low noise figure, high gain, high linearity and low current consumption over a wide range of supply voltages from 3.6 V down to 1.5 V. All these features make BGA231L7 an excellent choice for GNSS LNA as it improves sensitivity, provide greater immunity against out-of-band jammer signals, reduces filtering requirement and hence the overall cost of the GNSS receiver. This application note addresses the issue of out-of-band jammers and improving the immunity of BGA231L7 against these jammers. There is always a tradeoff between noise figure and out-of-band supression. The circuit designed here is inclined toward the applications where low noise figure is desired at the cost of out-of-band intermodulation products. The out-of-band signals considered are LTE Band-13, GSM850/900/1800, UMTS and WLAN as their intermodulation products fall into GPS band. The jamming resistance of BGA231L7 against these jammers is improved by increasing the attenuation of the circuit at these specific out-of-band frequencies (787MHz, 827MHz, 897MHz, 1712MHz, 1850MHz, 2402MHz, 2472MHz). This is achieved by using external SMDs and a SAW filter before BGA231L7. In some applications where more rejection is required at special frequencies and SAW filter alone cannot provide sufficient attenuation, some external notches can be designed for those frequencies. Figure 3 shows such an application circuit where notches have been designed to attenuate 787MHz, 827MHz, 897MHz, 2402 MHz and 2472MHz. The notches L3-C3/L4-C4 and L5-C5 are designed for 750-950MHz range and 2.45GHz respectively. The component values are fine tuned so as to have optimal noise figure, jammer rejection, gain and input matching. Application Note AN276, Rev. 1.0 7 / 22
Introduction The Internal circuit diagram of the BGA231L7 is presented in Figure 2. Table 1 shows the pin assignment of BGA231L7. Table 2 shows the truth table to turn on/off BGA231L7 by applying different voltage to the PON pin. Figure 2 Block diagram of the BGA231L7 for GNSS band 1559-1615MHz applications Table 1 Pin Definition Pin Symbol Comment 1 PON Power on control 2 AI LNA input 3 BIAS DC Bias 4 n.c. Not connected 5 AO LNA output 6 VCC DC Supply 7 GND RF and DC ground Table 2 Switching Mode Mode Symbol ON/OFF Control Voltage Min Max On PON, on 1.0V VCC Off PON, off 0 0.4 Application Note AN276, Rev. 1.0 8 / 22
Application Circuit 3 Application Circuit 3.1 Schematic Diagram RFin N2 SAW L2 Pon N1 BGA231L7 PON, 1 VCC, 6 AI, 2 AO, 5 RFout Vcc C1 L3 L4 L5 L1 BIAS, 3 GND, 7 n.c., 4 C3 C4 C5 Figure 3 BGA231L7 application circuit for improved rejection of out-of-band jammers Table 3 Bill-of-Materials Symbol Value Unit Package Manufacturer Comment C1 (optional) 10.0 nf 0201 Various RF bypass L1 39.0 nh 0201 Murata LQP series Biasing inductor L2 7.5 nh 0201 Murata LQP series Matching between SAW and LNA L3 10.0 nh 0201 Murata LQP series 750-950 MHz Notch C3 3.0 pf 0201 Various 750-950 MHz Notch L4 8.2 nh 0201 Murata LQP series 750-950 MHz Notch C4 4.3 pf 0201 Various 750-950 MHz Notch L5 2.8 nh 0201 Murata LQP series 2.45 GHz Notch C5 1.1 pf 0201 Various 2.45 GHz Notch N1 BGA231L7 TSLP-7-1 Infineon SiGe LNA N2 SAW TSNP-7-10 SAW filter of BGM1033N7 PCB substrate FR4 Application Note AN276, Rev. 1.0 9 / 22
Typical Measurement Results 4 Typical Measurement Results Table 4 and Table 5 show typical measurement results of the application circuit shown in Figure 3. The values given in this table include losses of the board and the SMA connectors if not otherwise stated. Table 4 Electrical Characteristics (at room temperature), Vcc = Vpon = 1.8V Parameter Symbol Value Unit Comment/Test Condition DC Voltage Vcc 1.8 V DC Current Icc 4.3 ma Frequency System Frequency Range Sys GPS GLONASS Freq 1575 1602-1615 MHz Gain G 14.9 14.4 db Noise Figure NF 2.1 2.45 db PCB and SMA connector losses of 0.07 db substracted Input Return Loss Output Return Loss Reverse Isolation RLin 10.7 11.0 db RLout 19.0 28.8 db IRev 23.7 23.9 db Input P1dB IP1dB -6.2-5.9 dbm Output P1dB OP1dB 7.7 7.5 dbm LTE band-13 2 nd Harmonic Output IM2 Out-of-band H2-75.0 dbm IM2-94.8 dbm f gps = f GLONASS = f IN = 787.76 MHz P IN = +15 dbm f 1 = 827 MHz, P 1IN = +12 dbm; f 2 = 2402 MHz, P 2IN = +8 dbm Output IM2 Out-of-band IM2-99.1 dbm f 1 = 897 MHz, P 1IN = +12 dbm; f 2 = 2472 MHz, P 2IN = +8 dbm Input IP3 In-band IIP3 0.7 dbm Output IP3 In-band OIP3 15.6 dbm Input IP3 Out-of-band IIP3 OOB 67.1 dbm Stability k >1 -- f 1 = 1575.5 MHz f 2 = 1576.5 MHz Input power= -30dBm f 1 = 1712.7 MHz, P 1IN = +10 dbm; f 2 = 1850 MHz, P 2IN = +10 dbm Unconditionnally Stable from 0 to 10GHz Application Note AN276, Rev. 1.0 10 / 22
Table 5 Electrical Characteristics (at room temperature), Vcc = Vpon = 2.8V Parameter Symbol Value Unit Comment/Test Condition DC Voltage Vcc 2.8 V DC Current Icc 4.5 ma Frequency System Frequency Range Sys GPS GLONASS Freq 1575 1602-1615 MHz Gain G 15.0 14.6 db Noise Figure NF 2.1 2.45 db PCB and SMA connector losses of 0.07 db substracted Input Return Loss Output Return Loss Reverse Isolation RLin 11.3 11.4 db RLout 17.2 34.9 db IRev 24.3 24.4 db Input P1dB IP1dB -3.5-3.1 dbm Output P1dB OP1dB 10.5 10.5 dbm LTE band-13 2 nd Harmonic Output IM2 Out-of-band H2-75.2 dbm IM2-95.0 dbm f gps = f GLONASS = f IN = 787.76 MHz P IN = +15 dbm f 1 = 827 MHz, P 1IN = +12 dbm; f 2 = 2402 MHz, P 2IN = +8 dbm Output IM2 Out-of-band IM2-99.4 dbm f 1 = 897 MHz, P 1IN = +12 dbm; f 2 = 2472 MHz, P 2IN = +8 dbm Input IP3 In-band IIP3 0.9 dbm Output IP3 In-band OIP3 15.9 dbm Input IP3 Out-of-band IIP3 OOB 67.1 dbm Stability k >1 -- f 1 = 1575.5 MHz f 2 = 1576.5 MHz Input power= -30dBm f 1 = 1712.7 MHz, P 1IN = +10 dbm; f 2 = 1850 MHz, P 2IN = +10 dbm Unconditionnally Stable from 0 to 10GHz Application Note AN276, Rev. 1.0 11 / 22
S21 (db) BGA231L7 Measured Graphs for GPS and GLONASS bands 5 Measured Graphs for GPS and GLONASS bands Figure 4 Power gain of BGA231L7 for GPS and GLONASS bands 16 15.5 Narrowband gain Gain at Vcc=1.8V Gain at Vcc=2.8V 15 14.5 15 db 14.9 db 14.6 db 14.4 db 14 13.5 13 1500 1525 1550 1575 1600 1625 1650 1675 1700 Frequency (MHz) Figure 5 Narrowband power gain of BGA231L7 for GPS and GLONASS bands Application Note AN276, Rev. 1.0 12 / 22
S22 (db) S11 (db) BGA231L7 Measured Graphs for GPS and GLONASS bands 0 Input matching S11 at Vcc=1.8V -5 S11 at Vcc=2.8V -10-10.69 db -10.95 db -11.33 db -11.41 db -15-20 -25 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 Frequency (MHz) Figure 6 Input matching of BGA231L7 for GPS and GLONASS bands 0 Output matching -5-10 S22 at Vcc=1.8V S22 at Vcc=2.8V -15-20 -17.2 db -19.04 db -25-30 -28.76 db -34.85 db -35 1000 1100 1200 1300 1400 1500 1600 1700 1800 1900 2000 Frequency (MHz) Figure 7 Output matching of BGA231L7 for GPS and GLONASS bands Application Note AN276, Rev. 1.0 13 / 22
NF (db) S12 (db) BGA231L7 Measured Graphs for GPS and GLONASS bands -20-25 -23.69 db -24.27 db -23.87 db -24.39 db Isolation S12 at Vcc=1.8V S12 at Vcc=2.8V -30-35 -40-45 -50 0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500 6000 Frequency (MHz) Figure 8 Reverse isolation of BGA231L7 for GPS and GLONASS bands 3.5 3.3 3.1 2.9 Noise figure NF at Vcc=1.8V NF at Vcc=2.8V 2.7 2.45 2.5 2.3 2.1 2.1 2.45 1.9 2.1 1.7 1.5 1559 1567 1575 1583 1591 1599 1607 1615 Frequency (MHz) Figure 9 Noise figure of BGA231L7 for GPS and GLONASS bands Application Note AN276, Rev. 1.0 14 / 22
Gain (db) Gain (db) BGA231L7 Measured Graphs for GPS and GLONASS bands 20 Compression point at 1dB with Vcc=1.8V P1dB at Vcc=1.8V GPS (1575MHz) P1dB at Vcc=1.8V GLONASS (1605MHz) 18 16-25 dbm 14.73 db -6.199 dbm 13.73 db 14-25 dbm 14.39 db 12-5.894 dbm 13.39 db 10-25 -20-15 -10-5 0 Power (dbm) Figure 10 Input 1 db compression point of BGA231L7 at supply voltage of 1.8V for GPS and GLONASS bands 20 Compression point at 1dB with Vcc=2.8V P1dB at Vcc=2.8V GPS (1575MHz) P1dB at Vcc=2.8V GLONASS (1605MHz) 18 16-25 dbm 14.86 db -3.471 dbm 13.86 db 14-25 dbm 14.51 db 12-3.136 dbm 13.51 db 10-25 -20-15 -10-5 0 Power (dbm) Figure 11 Input 1 db compression point of BGA231L7 at supply voltage of 2.8V for GPS and GLONASS bands Application Note AN276, Rev. 1.0 15 / 22
Power (dbm) Power (dbm) BGA231L7 Measured Graphs for GPS and GLONASS bands 0 Intermodulation for GPS band -10-20 -30 1575.5 MHz -15.15 1576.5 MHz -15.17-40 -50-60 -70 1577.5 MHz -76.69-80 -90-100 1573.5 1574.5 1575.5 1576.5 1577.5 1578.5 Frequency (MHz) Figure 12 Carrier and intermodulation products of BGA231L7 for GPS band at Vcc=1.8V 0 Intermodulation for GPS band -10-20 -30 1575.5 MHz -15.04 1576.5 MHz -15.07-40 -50-60 -70 1577.5 MHz -77.03-80 -90-100 1573.5 1574.5 1575.5 1576.5 1577.5 1578.5 Frequency (MHz) Figure 13 Carrier and intermodulation products of BGA231L7 for GPS band at Vcc=2.8V Application Note AN276, Rev. 1.0 16 / 22
Miscellaneous Measured Graphs 6 Miscellaneous Measured Graphs 3 Stability K factor Stability K factor at Vcc=1.8V Stability K factor at Vcc=2.8V 2 1.443 1.503 1 0 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 Frequency (MHz) Figure 14 Stability factor k of BGA231L7 upto 10GHz 3 Stability Mu1 factor Stability Mu1 factor at Vcc=1.8V Stability Mu1 factor at Vcc=2.8V 2 1.928 1 1.924 0 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 Frequency (MHz) Figure 15 Stability factor µ1 of BGA231L7 upto 10GHz Application Note AN276, Rev. 1.0 17 / 22
0-1.0 0.2 0.4 0.6 0.8 2.0 3.0 4.0 5.0 10.0 BGA231L7 Miscellaneous Measured Graphs 3 Stability Mu2 factor 2 1.554 1.63 1 Stability Mu2 factor at Vcc=1.8V Stability Mu2 factor at Vcc=2.8V 0 0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 Frequency (MHz) Figure 16 Stability factor µ2 of BGA231L7 upto 10GHz Input Input and Output matching with Vcc=1.8V Output 0.6 0.8 1.0 1.0 2.0 Swp Max 1615MHz 0.4 3.0 0.2 r 0.81988 x 0.101402 r 1.01514 x -0.0570512 4.0 5.0 10.0-0.2-0.4 r 0.63387 x -0.320972 r 0.636747 x -0.299718-3.0-10.0-5.0-4.0-2.0-0.6-0.8 Swp Min 1559MHz Figure 17 Input and output matching for GPS and GLONASS bands with Vcc=1.8V Application Note AN276, Rev. 1.0 18 / 22
0-1.0 0.2 0.4 0.6 0.8 2.0 3.0 4.0 5.0 10.0 BGA231L7 Miscellaneous Measured Graphs Input Input and Output matching with Vcc=2.8V Output 0.6 0.8 1.0 1.0 2.0 Swp Max 1615MHz 0.4 3.0 0.2 r 0.794992 x 0.144932 r 1.00382 x 0.0161302 4.0 5.0 10.0-0.2 r 0.647339 x -0.276686 r 0.662865 x -0.312783-10.0-5.0-4.0-0.4-3.0-2.0-0.6-0.8 Swp Min 1559MHz Figure 18 Input and output matching for GPS and GLONASS bands with Vcc=2.8V Application Note AN276, Rev. 1.0 19 / 22
Evaluation Board 7 Evaluation Board Figure 19 Populated PCB picture of BGA231L7 Vias FR4, 0.2mm Copper 35µm FR4, 0.8mm Figure 20 PCB layer stack Application Note AN276, Rev. 1.0 20 / 22
Authors 8 Authors Jagjit Singh Bal, Application Engineer of Business Unit RF and Protection Devices. Dr. Chih-I Lin, Senior Staff Engineer of Business Unit RF and Protection Devices. Application Note AN276, Rev. 1.0 21 / 22
w w w. i n f i n e o n. c o m Published by Infineon Technologies AG AN276