BF P842 E SD BF P842 E SD Si G e: C Ultr a L o w Nois e RF Tra nsi stor i n L o w Par ts C ount 2.4 – 2.5 GHz WL AN L N A Applic at ion (For 802.11 b / g / n Wireless LAN Applications) Applic atio n N ote A N 322 Revision: Rev. 1.0 2013-03-01 RF and P r otecti on D evic es Edition 2013-03-01 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. BFP842ESD BFP842ESD Ultra Low Noise Amplifier for 2.4 GHz - 2.5 GHz WLAN Application Application Note AN322 Revision History: 2013-03-01 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 AN322, Rev. 1.0 3 / 21 2013-03-01 BFP842ESD BFP842ESD Ultra Low Noise Amplifier for 2.4 GHz - 2.5 GHz WLAN Application List of Content, Figures and Tables Table of Content 1 1.1 Introduction ........................................................................................................................................ 5 ® Wi-Fi ................................................................................................................................................... 5 2 2.1 2.2 About BFP842ESD ............................................................................................................................. 7 Device Overview .................................................................................................................................. 7 Pin Assignment of BFP842ESD ........................................................................................................... 7 3 BFP842ESD as Ultra Low Noise Amplifier for 2.4GHz WLAN Applications ................................. 8 4 4.1 Performance Overview ...................................................................................................................... 9 Summary of Measurement Results ...................................................................................................... 9 5 Schematics and Bill-of-Materials .................................................................................................... 10 6 Measured Graphs ............................................................................................................................. 11 7 Evaluation Board and Layout Information .................................................................................... 18 8 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 Figure 19 Figure 20 ® 2.4 – 2.5 GHz Wi-Fi Wireless LAN (WLAN, IEEE802.11b/g/n) Front-End......................................... 5 Package and pin Assignment of BFP842ESD ..................................................................................... 7 Schematic Diagram of the used Circuit .............................................................................................. 10 Insertion Power Gain of the 2.4 – 2.5 GHz WLAN LNA with BFP842ESD ........................................ 11 Wideband Insertion Power Gain of the 2.4 – 2.5 GHz WLAN LNA with BFP842ESD ...................... 11 Noise figure of BFP842ESD for 2.4 – 2.5 GHz .................................................................................. 12 Reverse Isolation of the 2.4 – 2.5 GHz WLAN LNA with BFP842ESD.............................................. 12 Input Matching of the 2.4 – 2.5 GHz WLAN LNA with BFP842ESD .................................................. 13 Input Matching of the 2.4 – 2.5 GHz WLAN LNA with BFP842ESD (Smith Chart) ........................... 13 Output Matching of the 2.4 – 2.5 GHz WLAN LNA with BFP842ESD ............................................... 14 Output Matching of the 2.4 – 2.5 GHz WLAN LNA with BFP842ESD (Smith Chart) ........................ 14 Wideband Stability K Factor of the 2.4 – 2.5 GHz WLAN LNA with BFP842ESD ............................. 15 Wideband Stability Mu Factor of the 2.4 – 2.5 GHz WLAN LNA with BFP842ESD .......................... 15 Input 1dB compression point of the BFP842ESD circuit at 2400 MHz .............................................. 16 rd Output 3 Order Intercept Point of 2.4 GHz WLAN LNA with BFP842ESD ...................................... 16 OFF-Mode (Vcc = 0V, Icc = 0mA) S21 of the 2.4 – 2.5 GHz WLAN LNA with BFP842ESD ............ 17 Photo Picture of Evaluation Board for 2.4 – 2.5 GHz WLAN LNA with BFP842ESD ........................ 18 Zoom-In of Photo Picture of Evaluation Board for 2.4 – 2.5 GHz WLAN LNA with BFP842ESD ..... 18 Layout Proposal for RF Grounding of the 2.4 – 2.5 GHz WLAN LNA with BFP842ESD .................. 19 PCB Layer Information ....................................................................................................................... 19 List of Tables Table 1 Table 2 Summary of Measurement Results ...................................................................................................... 9 Bill-of-Materials................................................................................................................................... 10 Application Note AN322, Rev. 1.0 4 / 21 2013-03-01 BFP842ESD BFP842ESD Ultra Low Noise Amplifier for 2.4 GHz - 2.5 GHz WLAN Application Introduction 1 Introduction 1.1 Wi-Fi® The Wi-Fi® function is one of the most important connectivity functions in Access Point (AP) routers, notebooks, smart phones and tablet PCs. Wi-Fi® according to IEEE 802.11b/g/n at 2.4 GHz has been widely implemented over years. Different applications like home entertainment with wireless high-quality multimedia signal transmission, home networking notebooks, mass data storages and printers implement 2.4 – 2.5 GHz Wi-Fi® into their system to offer high-speed wireless connection. For this kind of high-speed high data rate wireless communication standards it is essential to ensure the quality of the link path. Major performance criteria of these equipments have to be fulfilled: sensitivity, strong signal capability and interference immunity. Below a general application diagram of a WLAN system is shown. Figure 1 ® 2.4 – 2.5 GHz Wi-Fi Wireless LAN (WLAN, IEEE802.11b/g/n) Front-End In order to increase the system sensitivity an excellent low noise amplifier (LNA) in front of the receiver is mandatory, especially in an environment with very weak signal strength and because of the insertion loss of the SPDT switch and the Bandpass Filter (BPF) or diplexer. The typical allowed overall system Noise Figure (NF) of the receiver chain of approx. 2 dB Application Note AN322, Rev. 1.0 5 / 21 2013-03-01 BFP842ESD BFP842ESD Ultra Low Noise Amplifier for 2.4 GHz - 2.5 GHz WLAN Application Introduction can only be achieved by using a high-gain low noise amplifier. As an example, to increase the sensitivity by 5 dB means doubled link distance. In addition, strong signal environment can exist when the equipment is next to a transmitter. In that case, the LNA must be linear enough, i.e. have high 1dB compression point. This avoids saturation, degradation of the gain and increased noise figure. The cloudy wireless environment nowadays makes the wireless system design more complicated. All kinds of interference might introduce signal distortion and reduce the real throughput data rate. To ensure that the low noise amplifier is not interfered by those signals good linearity characteristics like high IP3 are required. 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. Application Note AN322, Rev. 1.0 6 / 21 2013-03-01 BFP842ESD BFP842ESD Ultra Low Noise Amplifier for 2.4 GHz - 2.5 GHz WLAN Application About BFP842ESD 2 About BFP842ESD 2.1 Device Overview Infineon Technologies‟ BFP842ESD is a robust, high gain, ultra low noise SiliconGermanium-Carbon (SiGe: C) HBT device suitable for a wide range of Low Noise Amplifier (LNA) applications. The BFP842ESD is specifically designed and optimized for the 2.4 – 2.5 GHz frequency range in order to reduce external parts count, ease design effort and speed the end-user‟s time-to-market. Unlike some earlier-generation devices of the same general type used for this frequency range, this transistor does not require any external inductive emitter degeneration for impedance matching or stability considerations. BFP842ESD has integrated protection structures to guard against Electro Static Discharge (ESD) events up to 1 kV per Human Body Model (HBM), and these same structures also protect the transistor against damage caused by excessive RF input power levels up to +16 dBm. The device is housed in the industry-standard SOT343 package, which is RoHS-compliant and Halogenfree. 2.2 Pin Assignment of BFP842ESD B 1 4 E XYs E 2 3 C BFP842ESD Figure 2 Package and pin Assignment of BFP842ESD Application Note AN322, Rev. 1.0 7 / 21 2013-03-01 BFP842ESD BFP842ESD Ultra Low Noise Amplifier for 2.4 GHz - 2.5 GHz WLAN Application BFP842ESD as Ultra Low Noise Amplifier for 2.4GHz WLAN Applications 3 BFP842ESD as Ultra Low Noise Amplifier for 2.4GHz WLAN Applications The circuit shown is a Low Noise Amplifier (LNA) targeted for applications in the 2.4 – 2.5 GHz ISM band, with particular emphasis on Wireless LAN (WLAN) 802.11 b / g / n applications where lowest possible cost, low external parts count, and high receiver sensitivity / long range are primary goals. “0402” case size passives are used in the applications circuit described herein. Potential target applications include Wireless LAN Access Points, laptop PCs, Tablets, Gaming Consoles, etc. Generally, LNA‟s for these applications must be able to switch on & off within about 1 microsecond or less. The charge storage (capacitance) used in this circuit is minimized to reduce on / off times, and this LNA achieves a Turn-On (OFF->ON) switching time of about 390 nanoseconds, and a turn-off (ON->OFF) time of about 40 nanoseconds. The LNA is unconditionally stable over the 10 MHz – 15 GHz frequency range. External parts count (not including BFP842ESD) is 10: 5 capacitors, 3 resistors, and 2 chip inductors. Please refer to schematic diagram, Figure 3. At 2.4 GHz, the amplifier achieves about 19.3 dB gain (On-Mode) with a Noise Figure of 0.76 dB. (PCB and SMA losses are subtracted.) The Off-Mode gain is about -17.6 dB. The circuit achieves an input and output return loss more than 13 dB. At 2400 MHz, using two tones spacing of 1 MHz, the output third intercept point OIP3 reaches 21.9 dBm. Besides, we obtain 1dB input compression point IP1dB of -9.9 dBm at 2400 MHz. Application Note AN322, Rev. 1.0 8 / 21 2013-03-01 BFP842ESD BFP842ESD Ultra Low Noise Amplifier for 2.4 GHz - 2.5 GHz WLAN Application Performance Overview 4 Performance Overview Device: BFP842ESD Application: BFP842ESD Ultra Low Noise Amplifier for 2.4 GHz - 2.5 GHz WLAN Application PCB Marking: BFP842ESD SOT343 M130225 (PCB designed for 0402 SMDs) 4.1 Summary of Measurement Results Table 1 Summary of Measurement Results Parameter Symbol Value Unit DC Voltage Vcc 3.0 V DC Current Icc 11.9 mA Frequency Range Freq 2400 2500 MHz Gain (On Mode) GON 19.3 19.0 dB Gain (Off Mode) GOFF -17.6 -17.5 dB NF 0.76 0.76 dB Input Return Loss RLin 13.2 16.6 dB Output Return Loss Rlout 26.6 18.3 dB Irev 23.5 23.5 dB Input P1dB (On Mode) IP1dBON -9.9 -9.0 dBm Input P1dB (Off Mode) IP1dBOFF > 10 > 10 dBm Output P1dB (On Mode) OP1dBON 8.4 9.0 dBm Output P1dB (Off Mode) OP1dBOFF -- -- dBm IIP3 2,6 3,7 dBm Noise Figure Reverse Isolation Input IP3 Note/Test Condition SMA and PCB losses (0.05 dB) are subtracted Power @ Input: -25 dBm Output IP3 OIP3 21.9 22,7 dBm f1= 2400 MHz, f2= 2401 MHz f1’ = 2500 MHz, f2’ = 2501 MHz Stability k Application Note AN322, Rev. 1.0 -- >1 9 / 21 Stability measured from 10MHz to 15GHz 2013-03-01 BFP842ESD BFP842ESD Ultra Low Noise Amplifier for 2.4 GHz - 2.5 GHz WLAN Application Schematics and Bill-of-Materials 5 Figure 3 Table 2 Symbol Schematics and Bill-of-Materials Schematic Diagram of the used Circuit Bill-of-Materials Value Unit Size Manufacturer Comment C1 10 pF 0402 Various Input DC block C2 1.5 pF 0402 Various Output DC block, output matching C3 10 pF 0402 Various Input RF groud, input matching C4 6.8 pF 0402 Various RF decoupling / output matching C5 330 pF 0402 Various L1 3.3 nH 0402 LQG Input matching R1 39 kΩ 0402 Various DC biasing R2 33 Ω 0402 Various DC biasing R3 22 Ω 0402 Various Stability improvement Infineon Technologies BFP842ESD SiGe:C Heterojunction Bipolar RF Transistor Q1 Application Note AN322, Rev. 1.0 SOT 343 10 / 21 2013-03-01 BFP842ESD BFP842ESD Ultra Low Noise Amplifier for 2.4 GHz - 2.5 GHz WLAN Application Measured Graphs 6 Measured Graphs Insertion Power Gain InBand 20 2500 MHz 19 dB 2400 MHz 19.3 dB 15 10 5 0 2000 Figure 4 2500 3000 Frequency (MHz) 3500 4000 Insertion Power Gain of the 2.4 – 2.5 GHz WLAN LNA with BFP842ESD Insertion Power Gain WideBand 20 2500 MHz 19 dB 15 10 2400 MHz 19.3 dB 5 0 -5 0 5000 10000 15000 Frequency (MHz) Figure 5 Wideband Insertion Power Gain of the 2.4 – 2.5 GHz WLAN LNA with BFP842ESD Application Note AN322, Rev. 1.0 11 / 21 2013-03-01 BFP842ESD BFP842ESD Ultra Low Noise Amplifier for 2.4 GHz - 2.5 GHz WLAN Application Measured Graphs Noise Figure 2 NF(dB) 1.5 1 2400 MHz 0.76 dB 2500 MHz 0.77 dB 0.5 0 2400 Figure 6 2420 2440 2460 Frequency (MHz) 2480 2500 Noise figure of BFP842ESD for 2.4 – 2.5 GHz Reverse Isolation 0 -10 2400 MHz -23.5 dB 2500 MHz -23.2 dB -20 -30 -40 1000 Figure 7 1500 2000 2500 3000 3500 Frequency (MHz) 4000 4500 5000 Reverse Isolation of the 2.4 – 2.5 GHz WLAN LNA with BFP842ESD Application Note AN322, Rev. 1.0 12 / 21 2013-03-01 BFP842ESD BFP842ESD Ultra Low Noise Amplifier for 2.4 GHz - 2.5 GHz WLAN Application Measured Graphs Input Matching 0 2400 MHz -13.3 dB -5 2500 MHz -16.6 dB -10 -15 -20 -25 1000 Figure 8 1500 2000 2500 3000 3500 Frequency (MHz) 4000 4500 5000 Input Matching of the 2.4 – 2.5 GHz WLAN LNA with BFP842ESD Swp Max 5000MHz 2. 0 6 0. 0.8 1.0 Input Matching Smith 0. 4 0 3. 5.0 10.0 5.0 4.0 3.0 2.0 1.0 10.0 0.8 0.6 2400 MHz r 0.831692 x -0.369769 0.4 0.2 0.2 0 0 4. 2500 MHz r 0.847753 x -0.228086 -10.0 2 -0. 4 .0 -5. 0 -3 .0 Figure 9 .0 -2 -1.0 -0.8 -0 .6 .4 -0 Swp Min 1000MHz Input Matching of the 2.4 – 2.5 GHz WLAN LNA with BFP842ESD (Smith Chart) Application Note AN322, Rev. 1.0 13 / 21 2013-03-01 BFP842ESD BFP842ESD Ultra Low Noise Amplifier for 2.4 GHz - 2.5 GHz WLAN Application Measured Graphs Output Matching 10 0 -10 2500 MHz -18.3 dB 2400 MHz -26.6 dB -20 -30 1000 Figure 10 1500 2000 2500 3000 3500 Frequency (MHz) 4000 4500 5000 Output Matching of the 2.4 – 2.5 GHz WLAN LNA with BFP842ESD Swp Max 5000MHz 2. 0 6 0. 0.8 1.0 Output Matching Smith 0. 4 0.2 0 4. 5.0 10.0 10.0 5.0 4.0 3.0 2.0 1.0 0.8 0.6 0.4 2500 MHz r 1.26802 x -0.065443 0.2 0 0 3. 2400 MHz r 1.00914 x 0.093458 -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 2.4 – 2.5 GHz WLAN LNA with BFP842ESD (Smith Chart) Application Note AN322, Rev. 1.0 14 / 21 2013-03-01 BFP842ESD BFP842ESD Ultra Low Noise Amplifier for 2.4 GHz - 2.5 GHz WLAN Application Measured Graphs Stability k Factor 2 1.5 2577 MHz 1.1 1 0.5 0 0 5000 10000 15000 Frequency (MHz) Figure 12 Wideband Stability K Factor of the 2.4 – 2.5 GHz WLAN LNA with BFP842ESD Stability Mu Factor 2 1.5 1 Mu2 factor 0.5 Mu1 factor 0 100 5100 10100 15000 Frequency (MHz) Figure 13 Wideband Stability Mu Factor of the 2.4 – 2.5 GHz WLAN LNA with BFP842ESD Application Note AN322, Rev. 1.0 15 / 21 2013-03-01 BFP842ESD BFP842ESD Ultra Low Noise Amplifier for 2.4 GHz - 2.5 GHz WLAN Application Measured Graphs Input 1dB Compression Point 20 -30 dBm 19.3 dB Gain(dB) 15 -9.92 dBm 18.3 dB 10 5 0 -30 Figure 14 -25 -20 -15 Pin (dBm) -10 -5 0 Input 1dB compression point of the BFP842ESD circuit at 2400 MHz Output 3rd Order Intercept Point 0 2401 MHz -5.74 Power (dBm) -20 -40 2399 MHz -61 -60 -80 -100 2398.5 Figure 15 2399.5 2400.5 Frequency (MHz) 2401.5 2402.5 rd Output 3 Order Intercept Point of 2.4 GHz WLAN LNA with BFP842ESD Application Note AN322, Rev. 1.0 16 / 21 2013-03-01 BFP842ESD BFP842ESD Ultra Low Noise Amplifier for 2.4 GHz - 2.5 GHz WLAN Application Measured Graphs OFF Mode S21 0 2400 MHz -17.6 dB 2500 MHz -17.5 dB -20 -40 -60 -80 -100 1000 Figure 16 1500 2000 2500 3000 3500 Frequency (MHz) 4000 4500 5000 OFF-Mode (Vcc = 0V, Icc = 0mA) S21 of the 2.4 – 2.5 GHz WLAN LNA with BFP842ESD Application Note AN322, Rev. 1.0 17 / 21 2013-03-01 BFP842ESD BFP842ESD Ultra Low Noise Amplifier for 2.4 GHz - 2.5 GHz WLAN Application Evaluation Board and Layout Information 7 Evaluation Board and Layout Information Figure 17 Photo Picture of Evaluation Board for 2.4 – 2.5 GHz WLAN LNA with BFP842ESD Figure 18 Zoom-In of Photo Picture of Evaluation Board for 2.4 – 2.5 GHz WLAN LNA with BFP842ESD Application Note AN322, Rev. 1.0 18 / 21 2013-03-01 BFP842ESD BFP842ESD Ultra Low Noise Amplifier for 2.4 GHz - 2.5 GHz WLAN Application Evaluation Board and Layout Information Figure 19 Layout Proposal for RF Grounding of the 2.4 – 2.5 GHz WLAN LNA with BFP842ESD Vias FR4 Core, 0.2mm Copper 35µm Figure 20 FR4 Prepreg, 0.8mm PCB Layer Information Application Note AN322, Rev. 1.0 19 / 21 2013-03-01 BFP842ESD BFP842ESD Ultra Low Noise Amplifier for 2.4 GHz - 2.5 GHz WLAN Application Authors 8 Authors Shen Jianan, Internship Student of Application Engineering of Business Unit “RF and Protection Devices” Ahmed Shamsuddin, Application Engineer of Business Unit “RF and Protection Devices” Application Note AN322, Rev. 1.0 20 / 21 2013-03-01 w w w . i n f i n e o n . c o m Published by Infineon Technologies AG AN322