Application Note No. 124

Transcription

1 Application Note, Rev. 1.2, September 2007 Low Noise Amplifier for 2.3 to 2.5 GHz Applications using the SiGe BFP640F Tranistor Small Signal Discretes

2 Edition Published by Infineon Technologies AG München, Germany 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 your nearest Infineon Technologies Office ( Warnings Due to technical requirements components may contain dangerous substances. For information on the types in question please contact your nearest Infineon Technologies Office. Infineon Technologies Components may only be used in life-support devices or systems 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.

3 Revision History: , Rev. 1.2 Previous Version: , Rev. 1.1 Page Subjects (major changes since last revision) All Document layout change Application Note 3 Rev. 1.2,

4 1 Low Noise Amplifier for 2.3 to 2.5 GHz Applications using the SiGe BFP640F Tranistor Applications 2.4 GHz ISM band (Bluetooth, Cordless Phone, Wireless LAN, ZigBee, etc.) 2.33 GHz SDARS Satellite Radio (e.g. XM Radio ) Overview BFP640F in TSFP-4 package is evaluated for GHz LNA application. Note TSFP-4 package is only 1.4 x 1.2 x 0.55 mm high. Printed Circuit Board used is Infineon Part Number 640F Rev A. Standard FR4 material is used in a three-layer PCB. Please refer to cross-sectional diagram below. 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 < 40 mm². Total Parts count, including the BFP640 transistor, is 12. Target Specifications Design Goals: Gain = 15 db min, Noise Figure = 0.8 db max, Input / Output Return Loss 10 db or better, current < 7 ma from a 3.0 Volt power supply Summary of Results T = 25 C Table 1 Summary of Results Frequency MHz db[s11]² db[s21]² db[s12]² db[s22]² NF * db IIP 3 dbm OIP 3 dbm IP 1dB dbm OP 1dB dbm Achieved 15 db gain, 0.85 db Noise Figure at 2400 MHz from 3.0 V supply drawing 6.5 ma. Note noise figure result does NOT "back out" FR4 PCB losses - if PCB loss at LNA input were extracted, Noise Figure result would be approximately db lower. Amplifier is unconditionally stable from 5 MHz to 6 GHz. Input P 1dB = MHz. Outstanding Input Third Order Intercept (IIP 3 ) of dbm at 2400 MHz. PCB Cross - Section Diagram Figure 1 PCB - Cross Sectional Diagram Application Note 4 Rev. 1.2,

5 TSFP-4 Package Details (dimensions in millimeters) Note maximum package height is 0.59 mm / inch. 1.4± ± ± ± ± ± MAX. 0.15± ± ± ±0.05 GPX01010 Figure 2 Package Details of TSFP-4 Recommended Soldering Footprint for TSFP-4 (dimensions in millimeters). Device package is to be oriented as shown in above drawing (e.g. orient long package dimension horizontally on this footprint) HLGF1011 Figure 3 Package Footprint of TSFP-4 Application Note 5 Rev. 1.2,

6 Summary of LNA Data T = 25 C, network analyzer source power = -25 dbm Table 2 Summary of LNA Data Parameter Result Comments Frequency Range 2300 to 2500 MHz SDARS band, 2.4 GHz ISM band coverage DC Current V DC Voltage, V CC 3.0 V Collector-Emitter Voltage, V CE 2.5 V BFP640: V CEmax = 4.0 V Gain MHz MHz MHz Negligible change in gain or matching at 3.3 or 3.0 Volts Noise Figure MHz MHz MHz See Figure 5 and Table 4 (These values do NOT extract PCB losses, etc. resulting from FR4 board and passives used on PCB - these results are at input SMA connector) Input P 1dB MHz See Figure 10 Output P 1dB MHz Input 3 rd Order Intercept MHz Two tones, 2400 & 2401 MHz, - 16 dbm each tone. See Figure 17 and Figure 18 Output 3 rd Order Intercept MHz Input Return Loss MHz MHz MHz Output Return Loss MHz MHz MHz Reverse Isolation MHz MHz MHz Application Note 6 Rev. 1.2,

7 Bill of Material Table 3 Bill of Material REFERENCE VALUE MANUFACTURER CASE FUNCTION DESIGNATOR SIZE C1 33 pf Various 0402 DC Blocking, Input. Also, using cap above self-resonance makes it slightly inductive, slightly improving input match. C2 1.2 pf Various 0402 DC Block, Output. Also Influences Output and Input Impedance Match C µf Various 0402 Decoupling, Low Frequency. Also improves Third-Order Interception C4 8.2 pf Various 0402 Decoupling (RF Short) C5 5.6 pf Various 0402 Decoupling (RF Short). Also has influence on output match and stability. C µf Various 0402 Decoupling, Low Frequency L1 12 nh Murata LQP15HN Series Low Cost Inductor 0402 RF Choke at Input L2 3.9 nh Murata LQP15HN Series Low Cost Inductor 0402 RF Choke + Impedance Match at Output R1 10 Ω Various 0402 Stability Improvement R2 43 kω Various 0402 Brings Bias Current / Voltage into Base of Transistor R3 68 Ω Various 0402 Provides some Negative Feedback for DC BIAS / DC Operation Point to Compensate for Variations in Transistor DC Current Gain, Temperature Variations, etc. Q1 - Infineon Technologies TSFP-4 BFP640F B7HF Transistor J1, J2 - Johnson RF Input / Output Connectors J3 - AMP 5 Pin Header MTA-100 Series (standard pin plating) or (gold plated pins) - DC Connector Pins 1,5 = GROUND Pin 3 = V CC Pins 2,4 = no connection Application Note 7 Rev. 1.2,

8 Schematic Diagram for MHz LNA Figure 4 Schematic Diagram Application Note 8 Rev. 1.2,

9 Noise Figure, Plot. Center of Plot (x-axis) is 2400 MHz. Figure 5 Noise Figure Application Note 9 Rev. 1.2,

10 Noise Figure, Tabular Data MHZ to MHz From Rhode & Schwarz FSEK3 + FSEM30 System Preamplifier = MITEQ SMC-02 Table 4 Noise Figure Frequency Noise Figure 2200 MHz 0.88 db 2210 MHz 0.84 db 2220 MHz 0.88 db 2230 MHz 0.86 db 2240 MHz 0.87 db 2250 MHz 0.88 db 2260 MHz 0.85 db 2270 MHz 0.85 db 2280 MHz 0.87 db 2290 MHz 0.86 db 2300 MHz 0.87 db 2310 MHz 0.88 db 2320 MHz 0.88 db 2330 MHz 0.86 db 2340 MHz 0.85 db 2350 MHz 0.88 db 2360 MHz 0.85 db 2370 MHz 0.89 db 2380 MHz 0.85 db 2390 MHz 0.86 db 2400 MHz 0.85 db 2410 MHz 0.91 db 2420 MHz 0.90 db 2430 MHz 0.89 db 2440 MHz 0.87 db 2450 MHz 0.87 db 2460 MHz 0.86 db 2470 MHz 0.89 db 2480 MHz 0.84 db 2490 MHz 0.86 db 2500 MHz 0.88 db 2510 MHz 0.90 db 2520 MHz 0.89 db 2530 MHz 0.86 db 2540 MHz 0.88 db 2550 MHz 0.87 db Application Note 10 Rev. 1.2,

11 Table 4 Noise Figure (cont d) Frequency Noise Figure 2560 MHz 0.89 db 2570 MHz 0.87 db 2580 MHz 0.89 db 2590 MHz 0.88 db 2600 MHz 0.89 db Application Note 11 Rev. 1.2,

12 Scanned Image of PC Board Figure 6 Image of PC Board Application Note 12 Rev. 1.2,

13 Scanned Image of PC Board, Close-In Shot Figure 7 Image of PC Board, Close-In Shot Application Note 13 Rev. 1.2,

14 Scanned Image of PC Board, Backside of PSB Figure 8 Image of PC Board, Backside of PCB Application Note 14 Rev. 1.2,

15 Stability Factor "K" and Stability Measure "B1 Note that K > 1 and B 1 > 0, the amplifier is unconditionally stable. Measured LNA s-parameters were taken on a Network Analyzer & then imported into GENESYS simulation package, which calculates and plots K and B 1. Figure 9 Plot of K(f) and B 1 (f) Application Note 15 Rev. 1.2,

16 Power Sweep at 2400 MHz (CW) Source Power (Input) swept from -35 to -7 dbm Input P 1dB -10.0dBm Figure 10 Plot of Power Sweep (@ 2400 MHz) Application Note 16 Rev. 1.2,

17 Input Return Loss, Log Mag Figure 11 Plot of Input Return Loss Application Note 17 Rev. 1.2,

18 Input Return Loss, Smith Chart Reference Plane = Input SMA RF Connector Figure 12 Smith Chart of Input Return Loss Application Note 18 Rev. 1.2,

19 Forward Gain, wide Sweep 5 MHz to 6 GHz Figure 13 Plot of Forward Gain Application Note 19 Rev. 1.2,

20 Reverse Isolation Figure 14 Plot of Reverse Isolation Application Note 20 Rev. 1.2,

21 Output Return Loss, Log Mag Figure 15 Plot of Output Return Loss Application Note 21 Rev. 1.2,

22 Output Return Loss, Smith Chart Reference Plane = Output SMA RF Connector Figure 16 Smith Chart of Output Return Loss Application Note 22 Rev. 1.2,

23 Input Stimulus for Amplifier Two-Tone Test f 1 = 2400 MHz, f 2 = 2401 MHz, -16 dbm each tone. Figure 17 Tow-Tone Test, Input Stimulus Application Note 23 Rev. 1.2,

24 LNA Response to Two-Tone Test Input IP 3 = (59.8/2) = dbm Output IP 3 = dbm db gain = dbm Figure 18 Tow-Tone Test, LNA Response Application Note 24 Rev. 1.2,