Ap pl ica t io n N o te, Re v. 1 . 2, F e br ua ry 2 00 8 A p p li c a t i o n N o t e N o . 1 5 1 L o w N o i s e A m p l i fi e r ( L N A ) f o r 2 . 3 - 2 . 5 G H z A p pl i c a t i o n s U s i n g t h e S i G e B F P 6 4 0 T r a ns i s t o r R F & P r o t e c ti o n D e v i c e s Edition 2008-02-22 Published by Infineon Technologies AG 81726 München, Germany © Infineon Technologies AG 2009. 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. 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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 No. 151 Application Note No. 151 Revision History: 2008-02-22, Rev. 1.2 Previous Version: 2003-09-07, Rev. 1.1 Page Subjects (major changes since last revision) All Small changes in figure descriptions Application Note 3 Rev. 1.2, 2008-02-22 Application Note No. 151 Low Noise Amplifier (LNA) for 2.3 - 2.5 GHz Applications Using the SiGe 1 Low Noise Amplifier (LNA) for 2.3 - 2.5 GHz Applications Using the SiGe BFP640 Transistor Applications • 2.3 GHz SDARS, 2.4 GHz (Bluetooth, WiLAN, other 2.4 GHz ISM band applications) Overview • • • • • Design Goals: Gain =15 dB, Noise Figure < 1.2 dB, Input / Output Return Loss 10 dB or better, current < 7 mA from a 3.0 V power supply, Output P1dB > -15 dBm min. Printed Circuit Board used is Infineon Part Number 640-061603 Rev A. Standard FR4 material is used in a three-layer PCB. Please refer to cross-sectional diagram. Low-cost, standard "0402" case-size SMT passive components are used throughout. Please refer to schematic and Bill Of Material. The LNA is unconditionally stable from 5 MHz to 6 GHz. Total PCB area used for the single LNA stage is approximately 35 mm². Total Parts count, including the BFP640 transistor, is 12. Achieved 15 dB gain, 0.96 dB Noise Figure at 2400 MHz from a 3.0 V supply, drawing 6.7 mA. Note noise figure result does NOT "back out" FR4 PCB losses - if the PCB loss at LNA input were extracted, Noise Figure result would be approximately 0.2 dB lower. Amplifier is unconditionally stable from 5 MHz to 6 GHz. Input P1dB ≈ -13.1 dBm @ 2400 MHz. Outstanding Input Third Order Intercept of +11.6 dBm. PCB Cross - Section Diagram 7+,663$&,1*&5,7,&$/ 723/$<(5 LQFKPP ,17(51$/*5281'3/$1( LQFKPP" /$<(5)250(&+$1,&$/5,*,',7<2)3&%7+,&.1(66+(5(127 &5,7,&$/$6/21*$6727$/3&%7+,&.1(66'2(6127(;&((' ,1&+PP63(&,),&$7,21)25727$/3&%7+,&.1(66 ,1&+PPPP %27720/$<(5 $1B3&%YVG Figure 1 PCB - Cross Sectional Diagram Application Note 4 Rev. 1.2, 2008-02-22 Application Note No. 151 Low Noise Amplifier (LNA) for 2.3 - 2.5 GHz Applications Using the SiGe Summary of LNA Data T = 25 °C, Network analyzer source power = -25 dBm Table 1 Summary of Results Parameter Result Comments Frequency Range 2300 - 2500 MHz Covers SDARS 2.330 GHz band as well as 2.4 GHz ISM band. DC Current 6.7 mA DC Voltage, VCC 3.0 V Collector-Emitter Voltage, VCE 2.5 V BFP640: VCEmax = 4.0 V Gain 15.8 dB @ 2330 MHz 15.5 dB @ 2400 MHz 15.2 dB @ 2483 MHz Gain target: 15 dB min. Noise Figure 0.93 dB @ 2330 MHz 0.96 dB @ 2400 MHz 0.95 dB @ 2483 MHz See noise figure plots and tabular data, Figure 3 and Table 3. (These values do not extract PCB losses, etc. resulting from FR4 board an passives used on PCB these results are at input SMA connector) Input P1dB -11.3 dBm @ 2400 MHz See input power sweep vs. gain plot, Figure 7. Output P1dB +3.2 dBm @ 2400 MHz rd Input 3 Order Intercept +11.6 dB @ 2400 MHz Input Return Loss 10.5 dB @ 2330 MHz 11.5 dB @ 2400 MHz 12.8 dB @ 2483 MHz Output Return Loss 16.1 dB @ 2330 MHz 13.3 dB @ 2400 MHz 11.2 dB @ 2483 MHz Reverse Isolation 21.9 dB @ 2330 MHz 21.7 dB @ 2400 MHz 21.5 dB @ 2483 MHz Application Note 5 Two-Tone Test, see Figure 12 and Figure 13. Rev. 1.2, 2008-02-22 Application Note No. 151 Low Noise Amplifier (LNA) for 2.3 - 2.5 GHz Applications Using the SiGe Bill of Material Table 2 Bill of Material, Broadband BFP640 UHF Feedback LNA Reference Designator Value Manufacturer Case Size Function C1 8.2 pF Various 0402 DC blocking, input C2 1.5 pF Various 0402 DC block, output. Also influences output and input impedance match. C3 0.1 µF Various 0402 Decoupling, low frequency. Also improves Third-Order Intercept. C4 8.2 pF Various 0402 Decoupling (RF short) C5 5.6 pF Various 0402 Decoupling (RF short). Also has some influence on stability (using less than 8.2 pF causes output of amplifier to “see” more loss from R1 at lower frequencies → stability improvement). C6 0.1 µF Various 0402 Decoupling, low frequency L1 12 nH Murata LQP15M series 0402 RF choke at input L2 3.9 nH Murata LQP15M series 0402 RF choke + impedance match at output R1 10 Ω Various 0402 Stability improvement R2 51 kΩ Various 0402 Bring bias current / voltage into base of transistor R3 68 Ω Various 0402 Provides some negative feedback for DC bias / DC operating point to compensate for variations in transistor DC current gain, temperature variations, etc. Q1 - Infineon Technologies SOT343 BFP640 B7HF Transistor J1, J2 - Johnson 142-0701-841 - RF input / output connectors J3 - AMP 5 pin header MTA100 series 640456-5 (standard pin plating) or 641215-5 (gold plated pins) - DC connector Application Note Pins 1, 5 = ground Pin 3 = VCC Pins 2, 4 = no connection 6 Rev. 1.2, 2008-02-22 Application Note No. 151 Low Noise Amplifier (LNA) for 2.3 - 2.5 GHz Applications Using the SiGe Schematic Diagram for 2.3 - 2.5 GHz LNA 9FF 9 - '&&RQQHFWRU , P$ 5 RKPV 5 . & X) & S) & X) 5 RKPV / %ODFNUHFWDQJOHVDUHPLFURVWULS Q+ WUDFNVQRWFKLSFRPSRQHQWV 4 %)36L*H 7UDQVLVWRU / Q+ & S) & S) - 5)287387 - 5),1387 & S) 3&% 5HY$ 3&%RDUG0DWHULDO 6WDQGDUG)5 ,QGXFWLYH(PLWWHU'HJHQHUDWLRQ0LFURVWULSIRU ,3 LPSURYHPHQW5)PDWFKLQJ :LGWK LQFKPP /HQJWK LQFKPP %)39FH 9 $1B6FKHPDWLFYVG Figure 2 Schematic Diagram Application Note 7 Rev. 1.2, 2008-02-22 Application Note No. 151 Low Noise Amplifier (LNA) for 2.3 - 2.5 GHz Applications Using the SiGe Noise Figure, Plot, Center of Plot (x-axis) is 2400 MHz. 5RKGH6FKZDU])6(. 6HS 1RLVH)LJXUH (871DPH 0DQXIDFWXUHU 2SHUDWLQJ&RQGLWLRQV 2SHUDWRU1DPH 7HVW6SHFLILFDWLRQ &RPPHQW %)3*+]/1$ ,QILQHRQ7HFKQRORJLHV 9 9, P$7 & *HUDUG:HYHUV /:56'/1$3 2Q3&%5HY$ 6HSWHPEHU $QDO\]HU 5)$WW 5HI/YO G% G%P 5%: 9%: 0+] +] 5DQJH G% 5HI/YODXWR 21 0HDVXUHPHQW QGVWDJHFRUU 21 0RGH 'LUHFW (15 +3$(15 1RLVH)LJXUHG% 0+] 0+]',9 0+] $1BSORWBQIYVG Figure 3 Noise Figure Application Note 8 Rev. 1.2, 2008-02-22 Application Note No. 151 Low Noise Amplifier (LNA) for 2.3 - 2.5 GHz Applications Using the SiGe Noise Figure, Tabular Data From Rohde & Schwarz FSEK3 + FSEB30 System Preamplifier = MITEQ SMC-02 Table 3 Noise Figure Frequency Noise Figure 2200 MHz 0.93 dB 2225 MHz 0.94 dB 2250 MHz 0.97 dB 2275 MHz 0.96 dB 2300 MHz 0.96 dB 2325 MHz 0.93 dB 2350 MHz 0.96 dB 2375 MHz 0.96 dB 2400 MHz 0.96 dB 2425 MHz 0.95 dB 2450 MHz 0.95 dB 2475 MHz 0.95 dB 2500 MHz 0.96 dB 2525 MHz 0.95 dB 2550 MHz 0.95 dB 2575 MHz 0.97 dB 2600 MHz 0.97 dB Application Note 9 Rev. 1.2, 2008-02-22 Application Note No. 151 Low Noise Amplifier (LNA) for 2.3 - 2.5 GHz Applications Using the SiGe Scanned Image of PC Board Figure 4 Image of PC Board Application Note 10 Rev. 1.2, 2008-02-22 Application Note No. 151 Low Noise Amplifier (LNA) for 2.3 - 2.5 GHz Applications Using the SiGe Scanned Image of PC Board, Close-In Shot. Figure 5 Image of PC Board, Close-In Shot Application Note 11 Rev. 1.2, 2008-02-22 Application Note No. 151 Low Noise Amplifier (LNA) for 2.3 - 2.5 GHz Applications Using the SiGe Stability Factor K and Stability Measure B1 Note that if K > 1 and B1 > 0, the amplifier is unconditionally stable. Measured LNA s-parameters were taken on a Network Analyzer and then imported into GENESYS simulation package, which calculates and plots K and B1. $1BSORWBVWDELOLW\B.B%YVG Figure 6 Plot of K(f) and B1(f) Application Note 12 Rev. 1.2, 2008-02-22 Application Note No. 151 Low Noise Amplifier (LNA) for 2.3 - 2.5 GHz Applications Using the SiGe Power Sweep at 2400 MHz (CW) Source Power (Input) Swept from -25 to 0 dBm Input P1dB ≅ -11.3 dBm &+ 6 ORJ0$* 6HS 5()G% BG% G% G%P 35P BG% G%P &RU 0$5.(5 G%P 'HO 67$57G%P &:0+] 6723G%P $1BSORWBSRZHUBVZHHSYVG Figure 7 Plot of Power Sweep at 2400 MHz Application Note 13 Rev. 1.2, 2008-02-22 Application Note No. 151 Low Noise Amplifier (LNA) for 2.3 - 2.5 GHz Applications Using the SiGe Input Return Loss, Log Mag &+ 6 ORJ0$* G% 5()G% 6HS BG% 0+] 35P BG% *+] &RU BG% *+] 'HO 6PR 67$570+] 67230+] $1BSORWBLQSXWBUHWXUQBORVVYVG Figure 8 Plot of Input Return Loss Application Note 14 Rev. 1.2, 2008-02-22 Application Note No. 151 Low Noise Amplifier (LNA) for 2.3 - 2.5 GHz Applications Using the SiGe Forward Gain, Wide Sweep 5 MHz - 6 GHz &+ 6 ORJ0$* G% 5()G% 6HS BG% 0+] 35P BG% *+] &RU BG% *+] 'HO 6PR 67$570+] 67230+] $1BSORWBIZBJDLQYVG Figure 9 Plot of Forward Gain Application Note 15 Rev. 1.2, 2008-02-22 Application Note No. 151 Low Noise Amplifier (LNA) for 2.3 - 2.5 GHz Applications Using the SiGe Reverse Isolation &+ 6 ORJ0$* G% 5()G% 6HS BG% 0+] 35P BG% *+] &RU BG% *+] 'HO 6PR 67$570+] 67230+] $1BSORWBUHYHUVHBLVRODWLRQYVG Figure 10 Plot of Reverse Isolation Application Note 16 Rev. 1.2, 2008-02-22 Application Note No. 151 Low Noise Amplifier (LNA) for 2.3 - 2.5 GHz Applications Using the SiGe Output Return Loss, Log Mag &+ 6 ORJ0$* G% 5()G% 6HS BG% 0+] 35P BG% *+] &RU BG% *+] 'HO 6PR 67$570+] 67230+] $1BSORWBRXWSXWBUHWXUQBORVVYVG Figure 11 Plot of Output Return Loss Application Note 17 Rev. 1.2, 2008-02-22 Application Note No. 151 Low Noise Amplifier (LNA) for 2.3 - 2.5 GHz Applications Using the SiGe Two-Tone Test, 2400 MHz Input Stimulus for Amplifier Two-Tone Test. f1 = 2400 MHz, f2 = 2401 MHz, -17 dBm each tone. $1BSORWBWZRBWRQHBLQSXWYVG Figure 12 Tow-Tone Test, Input Stimulus @ 2400 MHz Application Note 18 Rev. 1.2, 2008-02-22 Application Note No. 151 Low Noise Amplifier (LNA) for 2.3 - 2.5 GHz Applications Using the SiGe Two-Tone Test, 2400 MHz LNA Response to Two-Tone Test. Input IP3 = -17 + (57.1 / 2) = +11.6 dBm Output IP3 = +11.6 dBm + 15.5 dB gain = +27.1 dBm $1BSORWBWZRBWRQHBUHVSRQVHYVG Figure 13 Tow-Tone Test, LNA Response @ 2400 MHz Application Note 19 Rev. 1.2, 2008-02-22 Application Note No. 151 Temperature Test, BFP640 2.4 GHz LNA Application, High DC Current Gain 2 Temperature Test, BFP640 2.4 GHz LNA Application, High DC Current Gain (High HFE) Device Sample November 6, 2003 Overview • Goal: determine if high HFE device (HDP Oxide, Ge Step) exhibits excessive performance shift and excessive DC operating point shift due to more extreme HFE versus Temperature curve inherent in high HFE devices. (Higher HFE target permits lower noise figure, however higher HFE also yields steeper negative slope of HFE versus Temperature curve.) Device tested has HFE of 187.4 @ T = 25 °C, VCE = 3.0 V, IC = 30 mA (Samples provided by J. Ramos, K. Gnannt). PCB = Infineon P/N 640-061603 Rev A. Network Analyzer source power = -20 dBm, VCC measured at PCB = 3.0 V. Summary of Data Table 4 Summary of Data Temp °C Freq. MHz dB[s11]² dB[s21]² dB[s12]² dB[s22]² Current mA -40 2330 11.7 16.4 21.8 19.2 7.9 -40 2400 12.9 16.2 21.5 14.9 7.9 -40 2483 14.3 15.9 21.3 12.3 7.9 +25 2330 10.8 15.7 21.9 15.7 6.8 +25 2400 11.8 15.4 21.7 12.7 6.8 +25 2483 13.0 15.1 21.5 10.6 6.8 +85 2330 10.5 15.0 21.9 12.6 6.2 +85 2400 11.6 14.7 21.7 10.6 6.2 +85 2483 12.7 14.4 21.6 9.0 6.2 • • • Comments bad S22 Total current shift, cold to hot ⇒ -1.7 mA Percent shift, cold to hot ⇒ 1.7 mA / 6.8 mA ⇒ 25 % Gain shift, cold to hot, 2400 MHz ⇒ 1.5 dB Overall Impression Results not as bad as expected. If voltage drop across R3 can be increased (e.g. trade off some VCE, by increasing R3, decrease R2 to maintain IC, yielding lower VCE) additional negative feedback can be obtained, which would further minimize DC current shift over temperature. AF PNP transistors are now < $0.01 U.S. in volume; active bias with PNP transistor would provide even more DC operating point stabilization. Use of AF PNP in TSFP-X or TSLP-X packages would minimize penalty on board space. If increased HFE really provides significant noise figure improvement, steeper HFE slope can be accommodated with more negative feedback in resistor bias circuit, or active bias can be employed. Application Note 20 Rev. 1.2, 2008-02-22 Application Note No. 151 Temperature Test, BFP640 2.4 GHz LNA Application, High DC Current Gain Cold, Input Return Loss (-40 °C) &+ 6 ORJ0$* G% 5()G% 1RY BG% 0+] BG% *+] &RU BG% *+] $YJ 6PR 67$570+] 67230+] $1BSORWBLQSXWBUHWXUQBORVVBFROGYVG Figure 14 Plot of Input Return Loss, Cold (-40 °C) Application Note 21 Rev. 1.2, 2008-02-22 Application Note No. 151 Temperature Test, BFP640 2.4 GHz LNA Application, High DC Current Gain Cold, Gain (-40 °C) &+ 6 ORJ0$* G% 5()G% 1RY BG% 0+] BG% *+] &RU BG% *+] $YJ 6PR 67$570+] 67230+] $1BSORWBJDLQBFROGYVG Figure 15 Plot of Gain, Cold (-40 °C) Application Note 22 Rev. 1.2, 2008-02-22 Application Note No. 151 Temperature Test, BFP640 2.4 GHz LNA Application, High DC Current Gain Cold, Reverse Isolation (-40 °C) &+ 6 ORJ0$* G% 5()G% 1RY BG% 0+] BG% *+] &RU BG% *+] $YJ 6PR 67$570+] 67230+] $1BSORWBUHYHUVHBLVRODWLRQBFROGYVG Figure 16 Plot of Reverse Isolation, Cold (-40 °C) Application Note 23 Rev. 1.2, 2008-02-22 Application Note No. 151 Temperature Test, BFP640 2.4 GHz LNA Application, High DC Current Gain Cold, Output Return Loss (-40 °C) &+ 6 ORJ0$* G% 5()G% 1RY BG% 0+] BG% *+] &RU BG% *+] $YJ 6PR 67$570+] 67230+] $1BSORWBRXWSXWBUHWXUQBORVVBFROGYVG Figure 17 Plot of Output Return Loss, Cold (-40 °C) Application Note 24 Rev. 1.2, 2008-02-22 Application Note No. 151 Temperature Test, BFP640 2.4 GHz LNA Application, High DC Current Gain Room Temp, Input Return Loss (+25 °C) &+ 6 ORJ0$* G% 5()G% 1RY BG% 0+] BG% *+] &RU BG% *+] $YJ 6PR 67$570+] 67230+] $1BSORWBLQSXWBUHWXUQBORVVBURRPYVG Figure 18 Plot of Input Return Loss, Room Temp (+25 °C) Application Note 25 Rev. 1.2, 2008-02-22 Application Note No. 151 Temperature Test, BFP640 2.4 GHz LNA Application, High DC Current Gain Room Temp, Gain (+25 °C) &+ 6 ORJ0$* G% 5()G% 1RY BG% 0+] BG% *+] &RU BG% *+] $YJ 6PR 67$570+] 67230+] $1BSORWBJDLQBURRPYVG Figure 19 Plot of Gain, Room Temp (+25 °C) Application Note 26 Rev. 1.2, 2008-02-22 Application Note No. 151 Temperature Test, BFP640 2.4 GHz LNA Application, High DC Current Gain Room Temp, Reverse Isolation (+25 °C) &+ 6 ORJ0$* G% 5()G% 1RY BG% 0+] BG% *+] &RU BG% *+] $YJ 6PR 67$570+] 67230+] $1BSORWBUHYHUVHBLVRODWLRQBURRPYVG Figure 20 Plot of Reverse Isolation, Room Temp (+25 °C) Application Note 27 Rev. 1.2, 2008-02-22 Application Note No. 151 Temperature Test, BFP640 2.4 GHz LNA Application, High DC Current Gain Room Temp, Output Return Loss (+25 °C) &+ 6 ORJ0$* G% 5()G% 1RY BG% 0+] BG% *+] &RU BG% *+] $YJ 6PR 67$570+] 67230+] $1BSORWBRXWSXWBUHWXUQBORVVBURRPYVG Figure 21 Plot of Output Return Loss, Room Temp (+25 °C) Application Note 28 Rev. 1.2, 2008-02-22 Application Note No. 151 Temperature Test, BFP640 2.4 GHz LNA Application, High DC Current Gain Hot, Input Return Loss (+85 °C) &+ 6 ORJ0$* G% 5()G% 1RY BG% 0+] BG% *+] &RU BG% *+] $YJ 6PR 67$570+] 67230+] $1BSORWBLQSXWBUHWXUQBORVVBKRWYVG Figure 22 Plot of Input Return Loss, Hot (+85 °C) Application Note 29 Rev. 1.2, 2008-02-22 Application Note No. 151 Temperature Test, BFP640 2.4 GHz LNA Application, High DC Current Gain Hot, Gain (+85 °C) &+ 6 ORJ0$* G% 5()G% 1RY BG% 0+] BG% *+] &RU BG% *+] $YJ 6PR 67$570+] 67230+] $1BSORWBJDLQBKRWYVG Figure 23 Plot of Gain, Hot (+85 °C) Application Note 30 Rev. 1.2, 2008-02-22 Application Note No. 151 Temperature Test, BFP640 2.4 GHz LNA Application, High DC Current Gain Hot, Reverse Isolation (+85 °C) &+ 6 ORJ0$* G% 5()G% 1RY BG% 0+] BG% *+] &RU BG% *+] $YJ 6PR 67$570+] 67230+] $1BSORWBUHYHUVHBLVRODWLRQBKRWYVG Figure 24 Plot of Reverse Isolation, Hot (+85 °C) Application Note 31 Rev. 1.2, 2008-02-22 Application Note No. 151 Temperature Test, BFP640 2.4 GHz LNA Application, High DC Current Gain Hot, Output Return Loss (+85 °C) &+ 6 ORJ0$* G% 5()G% 1RY BG% 0+] BG% *+] &RU BG% *+] $YJ 6PR 67$570+] 67230+] $1BSORWBRXWSXWBUHWXUQBORVVBKRWYVG Figure 25 Plot of Output Return Loss, Hot (+85 °C) Application Note 32 Rev. 1.2, 2008-02-22