H Philips Semiconductors B.V. Gerstweg 2, 6534 AE Nijmegen, The Netherlands Report nr. Author Date Department : RNR-T45-97-B-0789 : T. Buss th : 30 of September 97 : P.G. Transistors & Diodes, Development 2GHz LOW NOISE AMPLIFIER WITH THE BFG410W update of report RNR-T45-96-B-772 Abstract: This application note contains an example of a Low Noise Amplifier with the new BFG410W Double Poly RF-transistor. The LNA is designed for a frequency f=2GHz. The Noise Figure NF~1.7dB at f=2GHz and the gain S21 ~14dB. Appendix I: Schematic of the circuit Appendix II: Printlayout and list of used components & materials Appendix III: Results of simulations and measurements 1 H Philips Semiconductors B.V. Introduction: With the new Philips silicon bipolar double poly BFG400W series, it is possible to design low noise amplifiers for high frequency applications with a low current and a low supply voltage. These amplifiers are well suited for the new generation low voltage high frequency wireless applications. In this note a first study of such an amplifier will be given. This amplifier is designed for a working frequency of 2GHz. Designing the circuit: The circuit is designed to show the following performance: transistor: BFG410W Vce=2V, Ic =2mA, VSUP~3.3V freq=2GHz Gain~14dB NF<=1.7dB VSWRi<1:2 VSWRo<1:2 In the simulations the effect of extra RF-noise caused by the SMA-connectors was omitted, so in the practical situation the NF is ~0.1dB higher. This LNA is not optimised for the highest IP3. The IP3 can be optimised by: I. an extra series RC-decoupling of the base to the ground II. increasing IC With the solution I. two extra components are necessary, and with solution II, the Noise Figure of the LNA increases and the optimum source impedance also. The in- and outputmatching is realised with a LC-combination. Also extra emitter-inductance on both emitterleads (µ-strips) are used to improve the matching and the Noise Figure. Designing the layout: A lay-out has been designed with HP-MDS. Appendix II contains the printlayout. Measurements: Simulations (with realistic RF-models of al used parts) and measurements of the total circuit (epoxy PCB) are done (Appendix III). 2 H Philips Semiconductors B.V. Appendix I: Schematic of the circuit C3 C4 R1 +VSUP R3 C2 R4 µS3 µS1 R2 OUT 50Ω µS2 IN 50Ω C5 C7 W1 C1 BFG410W µS4: µS4 L1 L2 µS4 D1 L3 W2 Figure 1: LNA circuit 2 GHz LNA Component list: Component: Value: Comment: R1 R2 R3 R4 C1 C2 C3 C4 C5 C7 µs1 µs2 µs3 µs4 Bias. Better RF-stability (K>1). RF-block. Cancelling HFE-spread. Input match. 2GHz short. 2GHz short. RF-short Output match. Better RF-stability (K>1). µ-stripline Z0~95Ω (PCB: εr µ-stripline Z0~95Ω (PCB: εr µ-stripline Z0~95Ω (PCB: εr Emitter induction: µ-stripline 47 KΩ 10 Ω 22 Ω 560 Ω 1 pF 5.6 pF 5.6 pF 1 nF 3.3 pF 0.47 pF W=0.25mm W=0.25mm W=0.25mm (next table) 3 ~4.6, H=0.5mm) ~4.6, H=0.5mm) ~4.6, H=0.5mm) + via H Philips Semiconductors B.V. µS4 Emitter induction (µ-stripline + via): Name Dimension Description L1 2.0mm length µ-stripline; Z0 ~48Ω (PCB: εr ~4.6, H=0.5mm) L2 1.0mm length interconnect stripline and via-hole area L3 1.0mm length via-hole area W1 0.5mm width µ-stripline W2 1.0mm width via-hole area D1 0.4mm diameter of via-hole 4 H Philips Semiconductors B.V. Appendix II: Printlayout and list of used components & materials C1 R F i n C7 R2 RFout R1 C5 C2 C3 R3 Vsup R4 C4 BFG410W Figure 2: Printlayout 2GHz LNA Component list: Component: Value: size: R1 R2 R3 R4 C1 C2 C3 C4 C5 C5 PCB 47 KΩ 10 Ω 22 Ω 560 Ω 1 pF 5.6 pF 5.6 pF 1 nF 3.3 pF 0.47 pF εr ~4.6, H=0.5mm 0603 Philips 0603 Philips 0603 Philips 0603 Philips 0603 Philips 0603 Philips 0603 Philips 0603 Philips 0603 Philips 0603 Philips FR4 5 H Philips Semiconductors B.V. Appendix III: Results of simulations and measurements: BFG410W, Vsup=3.3V, VCE=2V, IC =2mA: HP-MDS Simulation: S-par. 2 |S21| [dB] 2 |S12| [dB] VSWRi VSWRo Noise Figure [dB] IP3 [dBm] (output) HP-MDS Simulation: SPICEmodel 14.6 -27.4 2.1 1.3 1.8 - 14.2 -24.6 2.6 1.3 1.6 - Measurements PCB: Comment: 14.3 -29.5 2.2 2.1 1.7 - not measured Figure 3: HP-MDS simulation circuit CMP453 M S V I A W =OWDv=Si0U a. 4B SmTm= s 1 0 m i l CMP230 M S V I A W=O WDvS=i U 0a . B 4 Sm Tm =s10mil L=L Wv=i W v i a CMP287 MSTL CMP5 SUBST=s10miM l SSUBSTRATE SUBST=s10mil W=L W=vLi va i E R = 4 . 6 HU=1.0E+3 m MUR=1 T=35um COND=5.8e07 CMP497 P h i l _ C 0 6 0 3 _ N P O _ l e v e H=0.5mm C = C o n t k o p ROUGH=10 CMP231 MSTL SUBST=s10mil um TAND=0.02 L=1 CMP265 L CMP452 M S V I A W=O WDvS=i U 0a . B 4 Sm Tm =s10mil CMP485 model cap. MSTL S U LB=SW=W5 0T. =3 s5 1m0mm i l LOW NOISE AMP. WITH BFG410W@2V/2mA CMP263 W =LW = vL ivai CMP227 C CMP487 CMP479 S U AB NS G R T ==W 90s 0.1=3005m d. m 2ei 5gm l m mM S T L MSTL SB1/BFG410I#3@2V/2mA MSRBND C=1 SUBST=s10mil SUBST=s10mil CMP486 L=1.6mm MSRBND W=W5 CMP264 W =R0 =. 20 5. 3m5mm m ANG=90 W=W5 L=3mm CMP498 P h i l _ C 0 6 0 3 _ N P O _ l e v e deg R C = C o n t k o p R=0.3 SUBST=s10mil W=0.25 CMP483 MSTL mm L=1 mm CMP503 P h i l _ R 0 6 0 3 _ l e v CMP504 CMP505 P h i l _ R 0 6 0 3 _ l e v SUBST=s10mil P h i l _ R 0 6 0 3 _ l e v L=100 SUBST=s10mil R = 4 7 k O H CMP481 R=22 OH R=560 OH CMP484 CMP482 CMP235 L CMP236 MSTL MSRBND MSRBND SUBST=s10mil ANG=90 SUBST=s10mil deg MSTL SB1/BFG410I#3@2V/2mA R=0.35mm W=0.25mm L=1.4mm W=W5 R =W 0 .=305. m 2 5mm m ANG=90 deg SUBST=s10mil W=W5 CMP480 MSTL L=0.35mm S12p=60.71 S22p=-32.33 S12m=0.045963 S22m=0.82784 S11p=- S 2 1 p = 1 2 2 . 6 S11m=0.6715 S21m=5.09682 JX1=0 JX2=0 W=W6 AGROUND CMP462 L=2.35mm MSTL SUBST=s10mil SUBST=s10mil CMP470 MSTL C = C i n C M P 3 5Z 9 MSTL 1=50 Z2=50 1 SUBST=s10mil L=6mm CMP18 PORT_SPAR PORTNUM=1 R=50 W=W50_Ohm CMP500 L=L3 P h i l _ C 0 6 0 3 _ N P O _ l e v e W=W3 CMP383 MSTL CMP502 P h i l _ R 0 6 0 3 _ l e v CMP358 MSTL CMP456 MSRBND ANG=90 2 SUBST=s10mil R=10 OH CMP460 MSTL CMP461 SUBST=s10mil L=L4 L=0.6mm W=W4 W=W6 SUBST=s10mil deg ANG=90 R=0.35mm SUBST=s10mil W=0.25mm SUBST=s10mil P h i l _ C 0 6 0 3 _ N P O _ l e v e CMP506 C = 0 . 4 7 W=0.25mm W=W6 R = 0W. 3= 50 .m2 m 5mm p F ANG=90 W=W6 S 2 P CMP457 deg W=W6 SUBST=s10mil CMP466 L=1.3mm MSTL AGROUND SUBST=s10mil CMP459 CMP468 CMP458 CMP350 MSTL mm E Q U A T I O NL 2 = ( 1 ) mm E Q U A T I O NL 3 = ( 0 . 6 ) E Q U A T I O NW 3 = ( 0 . 5 ) mm E Q U A T I O NL 4 = ( 0 . 3 ) E Q U A T I O NW 4 = ( 0 . 5 ) mm E Q U A T I O NL 5 = ( 8 ) mm E Q U A T I O NW 5 = ( 0 . 2 5 ) mm E Q U A T I O NL 6 = ( 5 ) mm E Q U A T I O NW 6 = ( 0 . 2 5 ) mm E Q U A T I O NL 7 = ( 7 ) mm E Q U A T I O NW 7 = ( 0 . 2 5 ) mm E Q U A T I O NW 8 = ( 0 . 2 5 ) mm mm W2=0.5 CMP252 MSTAPER MSRBND SUBST=s10mil mm SUBST=s10mil L=0.9mm L=0.9mm W=W6 W=W6 R = 0W. 3= 50 .m2 m 5mm ANG=90 deg W =R0 =. 20 5. 3m5mm m ANG=90 SUBST=s10mil SW U LB W1= v= iSaLT _ 2e= s 1 0 m i l deg SUBST=s10mil W 1S= U WB Lv S = i aT L_=2e s 1 0 m i l E Q U A T I O NW 5 0 _ O h m = ( 0 . 9 ) m m E Q U A T I O NL v i a = ( 0 . 2 5 ) E Q U A T I O NW v i a = ( 1 ) W2=0.5 CMP250 MSTL MSRBND W =L 0 .=5SL U1mBmS T = s 1 0 m i l MSTAPER CMP467 MSTL CMP351 MSTL W =L0 =. 5LS 1UmBmS T = s 1 0 m i l L=1.3mm MSTL SUBST=s10mil E Q U A T I O NL 1 = ( 2 ) deg R=0.35mm L=0.4mm CMP499 JX=0 CMP465 MSRBND S U B S TM = SsR B1N0D m i l mm E Q U A T I O NW v i a _ e = ( 1 ) mm CMP469 CMP180 CMP426 C=Cout M S V I A E Q U A T I O Nv s w r i = ( 1 + m a g ( s 1 1 ) ) / ( 1 E Q U A T I O Nv s w r o = ( 1 + m a g ( s 2 2 ) ) / ( 1 - W=Wvia_e OD=0.4 mm SUBST=s10mil MSTL M S V I A W=Wvia_e OD=0.4 mm SUBST=s10mil SUBST=s10mil E Q U A T I O NC i n = ( 1 . 0 ) CMP501 P h i l _ C 0 6 0 3 _ N P O _ l e v e E Q U A T I O NC o u t = ( 3 . 3 ) L=6mm PORTNUM=2 W = W 5 0 _ O h mC M P 2 7 0 PORT_SPAR E Q U A T I O NC o n t k o p = ( 5 . 6 ) R=50 JX=0 AGROUND 6