BF P650 High Lin e arit y Lo w Nois e A m plifier using BF P 650 f or 2. 4 GHz WL AN Applic atio n Applic atio n N ote A N 329 Revision: Rev. 1.0 2013-06-21 RF and P r otecti on D evic es Edition 2013-06-21 Published by Infineon Technologies AG 81726 Munich, Germany © 2013 Infineon Technologies AG All Rights Reserved. Legal Disclaimer The information given in this document shall in no event be regarded as a guarantee of conditions or characteristics. With respect to any examples or hints given herein, any typical values stated herein and/or any information regarding the application of the device, 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. 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. BFP650 High Linearity LNA for 2.4 GHz WLAN Application Application Note AN329 Revision History: 2013-06-21 Previous Revision: No previous revision Page Subjects (major changes since last revision) Trademarks of Infineon Technologies AG AURIX™, C166™, CanPAK™, CIPOS™, CIPURSE™, EconoPACK™, CoolMOS™, CoolSET™, CORECONTROL™, CROSSAVE™, DAVE™, DI-POL™, EasyPIM™, EconoBRIDGE™, EconoDUAL™, EconoPIM™, EconoPACK™, EiceDRIVER™, eupec™, FCOS™, HITFET™, HybridPACK™, I²RF™, ISOFACE™, IsoPACK™, MIPAQ™, ModSTACK™, my-d™, NovalithIC™, OptiMOS™, ORIGA™, POWERCODE™, 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. 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 Application Note AN329, Rev. 1.0 3 / 21 2013-06-21 BFP650 High Linearity LNA for 2.4 GHz WLAN Application List of Content, Figures and Tables Table of Content 1 1.1 Introduction ........................................................................................................................................ 5 ® About Wi-Fi /Wireless LAN (WLAN) ................................................................................................... 5 2 2.1 2.2 BFP650 Overview ............................................................................................................................... 7 Features ............................................................................................................................................... 7 Key Applications of BFP650 ................................................................................................................. 7 3 3.1 3.2 3.3 BFP650 as Low Noise Amplifier for 2.4–2.5 GHz Wireless LAN Applications ............................ 8 Description ........................................................................................................................................... 8 Performance Overview ......................................................................................................................... 9 Schematics and Bill-of-Materials ........................................................................................................ 10 4 Measurement Graphs ...................................................................................................................... 12 5 Evaluation Board and Layout Information .................................................................................... 18 6 Authors .............................................................................................................................................. 20 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 The 2.4 GHz WLAN (IEEE802.11b/g/n/a/c/ac) Front-End System Block Diagram. ............................ 5 BFP650 in SOT343 .............................................................................................................................. 7 Schematic Diagram of the Application Circuit .................................................................................... 10 Insertion Power Gain Wideband of the 2400-2500 MHz WLAN LNA with BFP650 .......................... 12 Insertion Power Gain Inband of the 2400-2500 MHz WLAN LNA with BFP650 ................................ 12 Reverse Isolation of the 2400-2500 MHz WLAN LNA with BFP650 .................................................. 13 Noise figure of the 2400-2500 MHz WLAN LNA with BFP650 .......................................................... 13 Input Matching of the 2400-2500 MHz WLAN LNA with BFP650 ...................................................... 14 Input Matching of the 2400-2500 MHz WLAN LNA with BFP650 (Smith Chart) ............................... 14 Output Matching of the 2400-2500 MHz WLAN LNA with BFP650 ................................................... 15 Output Matching of the 2400-2500 MHz WLAN LNA with BFP650 (Smith Chart) ............................ 15 Input 1dB compression point of the BFP650 LNA at 2400 MHz ........................................................ 16 Wideband Stability K Factor of the 2400-2500 MHz WLAN LNA with BFP650 ................................. 16 Wideband Stability Mu Factor of the 2400-2500 MHz WLAN LNA with BFP650 .............................. 17 rd Output 3 Order Intercept Point of BFP650 LNA at 2400 MHz ......................................................... 17 Photo of the BFP650 2400-2500 MHz LNA Evaluation Board .......................................................... 18 Zoom-in Pictutre of the BFP650 2400-2500 MHz LNA Evaluation Board ......................................... 18 PCB Layer Information ....................................................................................................................... 19 List of Tables Table 1 Table 2 Summary of Measurement Results ...................................................................................................... 9 Bill-of-Materials................................................................................................................................... 10 Application Note AN329, Rev. 1.0 4 / 21 2013-06-21 BFP650 High Linearity LNA for 2.4 GHz WLAN Application Introduction 1 Introduction 1.1 About Wi-Fi® /Wireless LAN (WLAN) Wireless Fidelity (Wi-Fi ) or the well-known Wireless LAN (WLAN) plays a major role in today’s communications by enabling constant connection in the 2.4 GHz and broadband Internet access for users with laptops or devices equipped with wireless network interface while roaming within the range of fixed Access Points (AP) or a public hotspot. Different applications like home entertainment with wireless high-quality multimedia signal transmission, home networking notebooks, mass data storages and printers implement 2.4 GHz wireless data transfer functions into their system for the connectivity convinience. For this kind of high-speed and high data rate wireless communication standards, it is essential to ensure the data transfer quality of the link path. Major performance criteria of these equipments have to be fulfilled: sensitivity, strong signal capability and interference immunity. Fig.1 presents a general block diagram of the WLAN system. Figure 1 The 2.4 GHz WLAN (IEEE802.11b/g/n/a/c/ac) Front-End System Block Diagram. The Wi-Fi router provides the ability to receive relatively weak signals from Wi-Fi enabled devices such as mobile phones. Therefore, it should have high sensitivity to detect a weak signal in the presence of strong interfering signals. The sensitivity of the receiver can be improved by using a low noise amplifier (LNA) as a first block of the receiver front-end to increase the signal-to-noise ratio (SNR) of the overall system, especially in an environment with very weak signal strength. Due to the insertion loss of the single-pole-double-throw (SPDT) switch and the Bandpass Filter (BPF) or diplexer, the typical allowed receiver chain Noise Figure (NF) of approx. 2 dB can only be achieved by using a high-gain LNA. In addition, the WLAN systems are subject to co-channel interference and the interference from strong co-existing cellular signals. High linearity Application Note AN329, Rev. 1.0 5 / 21 2013-06-21 BFP650 High Linearity LNA for 2.4 GHz WLAN Application Introduction characteristics of the LNA, such as the 3rd order intercept point ( ( 1dB ), 3) and 1dB compression point are required to improve the ability to distinguish between desired signals and interference signals received close together. This application note is focusing on the LNA block, but Infineon does also support with RFswitches, TVS-diodes for ESD protection and RF Schottky diodes for power detection for WLAN. Application Note AN329, Rev. 1.0 6 / 21 2013-06-21 BFP650 High Linearity LNA for 2.4 GHz WLAN Application BFP650 Overview 2 BFP650 Overview 2.1 Features • Linear low noise driver amplifier for RF front-end up to 5 GHz, based on Infineon´s reliable, high volume SiGe:C wafer technology • High Output compression point 1dB 17 dBm at 70 mA, 3 V, 2.4 GHz, 50 Ω system • High Output 3rd order intermodulation point 3 30 dBm at 70 mA, 3 V, 2.4 GHz, 50 Ω system • Maximum available gain max Figure 2 BFP650 in SOT343 17.5 dB at 70 mA, 3 V, 2.4 GHz • Minimum noise figure min 1 dB at 30 mA, 3 V, 2.4 GHz • Easy to use Pb-free (RoHS compliant) and halogen-free standard package with visible leads 2.2 Key Applications of BFP650 Driver amplifier: • ISM bands 434 and 868 MHz • 1.9 GHz cordless phones • CATV LNA amplifiers • ISM bands up to 10 GHz Transmitter driver amplifier • 2.4 GHz WLAN / Bluetooth, 2.4 / 3.5 GHz WiMAX Output stage LNA for active antennas • TV, GPS, SDARS • 2.4 / 5 GHz WLAN • 2.4 / 3.5 / 5 GHz WiMAX, etc Suitable for 5-10.5 GHz oscillators Application Note AN329, Rev. 1.0 7 / 21 2013-06-21 BFP650 High Linearity LNA for 2.4 GHz WLAN Application BFP650 as Low Noise Amplifier for 2.4–2.5 GHz Wireless LAN Applications 3 BFP650 as Low Noise Amplifier for 2.4–2.5 GHz Wireless LAN Applications 3.1 Description BFP650 from Infineon Technologies is a low cost discrete SiGe:C hetero-junction bipolar transistor (HBT) specifically designed for WLAN LNA with high power applications. This report presents the application circuit with the low-cost SiGe BFP650 RF transistor as LNA for 2.4 GHz WLAN application. The circuit requires 11 external SMDs (0402 case size). The LNA provides gain from 11.7 dB to 12.1 dB over the WLAN band from 2.4 GHz to 2.5 GHz, and the noise figure (NF) varies from 0.92 dB to 0.97 dB (SMA and PCB losses are subtracted) over the complete frequency band. Furthermore, the circuit provides unconditional stability from 10 MHz to 15 GHz. The circuit is matched at input and output, and presents an input return loss more than 11.9 dB, and an output return loss more than 10.8 dB. At the frequency of 2.4 GHz, using two tones spaced of 1MHz, the output 3rd intercept point reaches +20.9 dBm. Besides, the measured input 1 dB compression point at 2.4 GHz is -3.4 dBm. Application Note AN329, Rev. 1.0 8 / 21 2013-06-21 BFP650 High Linearity LNA for 2.4 GHz WLAN Application BFP650 as Low Noise Amplifier for 2.4–2.5 GHz Wireless LAN Applications 3.2 Performance Overview Device: BFP650 Application: High Linearity LNA for 2.4 GHz WLAN Application PCB Marking: BFP740 SOT343, 740-080704 Rev A Table 1 Summary of Measurement Results Parameter Symbol Value Unit DC Voltage Vcc 3.0 V DC Current Icc 14.2 mA Frequency Range Note/Test Condition Freq 2400 2500 MHz Gain G 12.1 11.7 dB Noise Figure NF 0.92 0.97 dB RLin 11.9 12.1 dB RLout 12.0 10.8 dB IRev 17.2 16.9 dB Input P1dB IP1dB -3.4 -3.2 dBm Output P1dB OP1dB 7.7 7.5 dBm Input IP3 IIP3 8.8 dBm Output IP3 OIP3 20.9 dBm f=2400 MHz, Δf=1 MHz, Pin= -25 dBm -- Stability measured from 10 MHz to 15 GHz Input Return Loss Output Return Loss Reverse Isolation Stability k Application Note AN329, Rev. 1.0 >1 9 / 21 SMA and PCB losses (~0.08 dB) are subtracted 2013-06-21 BFP650 High Linearity LNA for 2.4 GHz WLAN Application BFP650 as Low Noise Amplifier for 2.4–2.5 GHz Wireless LAN Applications 3.3 Schematics and Bill-of-Materials Vcc= 3.0 V All passives are “0402“ case size Inductors: LQG Series Capacitors: various J3 DC Connector I = 14.2 mA R3 20 Ohms R2 33k Ohms C3 33 pF C5 1 nF R1 9.1 Ohms L1 12 nH L2 5.1 nH J1 RF Port1 INPUT C4 8.2 pF Q1: BFP650 C2 C1 J2 RF Port2 OUTPUT 2.2 pF 3.3 pF C6 1 pF Inductive Emitter Degeneration Micro Stripline (refer to Gerber-file) PCB = 740-080704 Rev A PCB Board Material = Standard FR4 Layer spacing (top RF to internal ground plane): 0.305 mm Figure 3 Table 2 Symbol Total Component Count = 11 Inductors = 2 (LQG Low-Q series) Resistors = 3 Capacitors = 6 Schematic Diagram of the Application Circuit Bill-of-Materials Value Unit Size Manufacturer Comment C1 3.3 pF 0402 Various DC block & input matching C2 2.2 pF 0402 Various DC block & output matching C3 33 pF 0402 Various RF decoupling C4 8.2 pF 0402 Various C5 1.0 nF 0402 Various Output matching RF decoupling C6 1.0 pF 0402 Various Input matching L1 12 nH 0402 LQG series input matching and bias to the Base L2 5.1 nH 0402 LQG series Output matching and bias to the Collector R1 9.1 Ω 0402 Various Inband stability improvement R2 33 kΩ 0402 Various R3 20 Ω 0402 Various Base biasing DC biasing (provides DC negative Application Note AN329, Rev. 1.0 10 / 21 2013-06-21 BFP650 High Linearity LNA for 2.4 GHz WLAN Application BFP650 as Low Noise Amplifier for 2.4–2.5 GHz Wireless LAN Applications Table 2 Symbol Bill-of-Materials Value Unit Q1 Application Note AN329, Rev. 1.0 Size SOT343 Manufacturer Infineon Technologies 11 / 21 Comment feedback to stabilize DC operating point over temperature variation, transistor hFE variation, etc.) BFP650 low-cost SiGe:C RF transistor 2013-06-21 BFP650 High Linearity LNA for 2.4 GHz WLAN Application Measurement Graphs 4 Measurement Graphs Insertion Power Gain WideBand 15 2500 MHz 11.7 dB 5 2400 MHz 12.1 dB -5 -15 -25 -35 1000 Figure 4 6000 Frequency (MHz) 11000 15000 Insertion Power Gain Wideband of the 2400-2500 MHz WLAN LNA with BFP650 Insertion Power Gain InBand 15 2400 MHz 12.1 dB 10 2500 MHz 11.7 dB 5 0 2000 Figure 5 2500 3000 Frequency (MHz) 3500 4000 Insertion Power Gain Inband of the 2400-2500 MHz WLAN LNA with BFP650 Application Note AN329, Rev. 1.0 12 / 21 2013-06-21 BFP650 High Linearity LNA for 2.4 GHz WLAN Application Measurement Graphs Reverse Isolation 0 -10 -20 2400 MHz -17.2 dB 2500 MHz -16.9 dB -30 -40 1000 Figure 6 2000 3000 4000 Frequency (MHz) 5000 6000 Reverse Isolation of the 2400-2500 MHz WLAN LNA with BFP650 Noise Figure 1.5 1.4 1.3 NF(dB) 1.2 1.1 2500 MHz 0.97 dB 2400 MHz 0.92 dB 1 0.9 0.8 0.7 0.6 0.5 2400 Figure 7 2420 2440 2460 Frequency (MHz) 2480 2500 Noise figure of the 2400-2500 MHz WLAN LNA with BFP650 Application Note AN329, Rev. 1.0 13 / 21 2013-06-21 BFP650 High Linearity LNA for 2.4 GHz WLAN Application Measurement Graphs Input Matching 0 -5 2400 MHz -11.9 dB -10 2500 MHz -12.1 dB -15 1000 Figure 8 1500 2000 2500 3000 3500 4000 Frequency (MHz) 4500 5000 5500 6000 Input Matching of the 2400-2500 MHz WLAN LNA with BFP650 Swp Max 4000MHz 2. 0 6 0. 0.8 1.0 Input Matching Smith 0. 4 0 3. 0 4. 5.0 0.2 10.0 5.0 4.0 3.0 10.0 2.0 1.0 0.8 0.6 0.4 0 0.2 2400 MHz r 0.680335 x -0.289791 2500 MHz r 0.700312 x -0.309178 -4 .0 -5. 0 -3 .0 .0 -2 -1.0 -0.8 -0 .6 .4 -0 Figure 9 -10.0 2 -0. Swp Min 1000MHz Input Matching of the 2400-2500 MHz WLAN LNA with BFP650 (Smith Chart) Application Note AN329, Rev. 1.0 14 / 21 2013-06-21 BFP650 High Linearity LNA for 2.4 GHz WLAN Application Measurement Graphs Output Matching 0 -5 2400 MHz -12 dB 2500 MHz -10.8 dB -10 -15 -20 -25 -30 1000 Figure 10 1500 2000 2500 3000 3500 4000 Frequency (MHz) 4500 5000 5500 6000 Output Matching of the 2400-2500 MHz WLAN LNA with BFP650 Swp Max 4000MHz 2. 0 6 0. 0.8 1.0 Output Matching Smith 0. 4 0 3. 0 4. 5.0 10.0 5.0 4.0 2500 MHz r 1.63598 x -0.439316 3.0 2.0 1.0 10.0 0.8 0.6 0.4 0 0.2 0.2 2400 MHz r 1.5794 x -0.295666 -10.0 2 -0. -4 .0 -5. 0 -3 .0 Figure 11 .0 -2 -1.0 -0.8 -0 .6 .4 -0 Swp Min 1000MHz Output Matching of the 2400-2500 MHz WLAN LNA with BFP650 (Smith Chart) Application Note AN329, Rev. 1.0 15 / 21 2013-06-21 BFP650 High Linearity LNA for 2.4 GHz WLAN Application Measurement Graphs Input 1dB Compression Point at 2400MHz 15 -30 dBm 12.09 dB -3.396 dBm 11.09 dB Gain(dB) 10 5 0 -30 Figure 12 -25 -20 -15 Pin (dBm) -10 -5 0 Input 1dB compression point of the BFP650 LNA at 2400 MHz Stability k Factor 2 1.5 1 1736.6 MHz 1.03 0.5 0 10 5010 10010 15000 Frequency (MHz) Figure 13 Wideband Stability K Factor of the 2400-2500 MHz WLAN LNA with BFP650 Application Note AN329, Rev. 1.0 16 / 21 2013-06-21 BFP650 High Linearity LNA for 2.4 GHz WLAN Application Measurement Graphs Stability Mu Factor 2 1.5 1 Mu2 factor 0.5 Mu1 factor 0 10 5010 10010 15000 Frequency (MHz) Figure 14 Wideband Stability Mu Factor of the 2400-2500 MHz WLAN LNA with BFP650 Output 3rd Order Intercept Point 0 2400.0 MHz -12.6 Power (dBm) -20 -40 -60 2402.0 MHz -79.5 -80 -100 2398.5 Figure 15 2399.5 2400.5 Frequency (MHz) 2401.5 2402.5 rd Output 3 Order Intercept Point of BFP650 LNA at 2400 MHz Application Note AN329, Rev. 1.0 17 / 21 2013-06-21 BFP650 High Linearity LNA for 2.4 GHz WLAN Application Evaluation Board and Layout Information 5 Evaluation Board and Layout Information Figure 16 Photo of the BFP650 2400-2500 MHz LNA Evaluation Board Figure 17 Zoom-in Pictutre of the BFP650 2400-2500 MHz LNA Evaluation Board Application Note AN329, Rev. 1.0 18 / 21 2013-06-21 BFP650 High Linearity LNA for 2.4 GHz WLAN Application Evaluation Board and Layout Information Vias FR4 Core, 0.305 mm Copper 35µm Figure 18 FR4 Prepreg, 0.711 mm PCB Layer Information Application Note AN329, Rev. 1.0 19 / 21 2013-06-21 BFP650 High Linearity LNA for 2.4 GHz WLAN Application Authors 6 Authors Shamsuddin Ahmed, Application Engineer of Business Unit “RF and Protection Devices” Dr. Chih-I Lin, Senior Staff Engineer/Technical Marketing RF of Business Unit “RF and Protection Devices” 7 Remark The graphs are generated with the simulation program AWR Microwave Office®. Application Note AN329, Rev. 1.0 20 / 21 2013-06-21 w w w . i n f i n e o n . c o m Published by Infineon Technologies AG AN329