A p p l i c a t i o n N o t e , R e v . 1 . 2 , A ug us t 2 00 7
A p p li c a t i o n N o t e N o . 1 1 3
D u a l - B a n d / B r o a d b an d F ee d b a c k L ow N oi s e
A m p l i f i e r f or < 2 . 4 G H z t o 6 G H z i n c l us i v e , u s i n g
t h e U l t r a L o w N oi s e B F R 74 0 L 3 S i G e : C T r a n s i s t o r
R F & P r o t e c ti o n D e v i c e s
Edition 2007-08-30
Published by
Infineon Technologies AG
81726 München, Germany
© Infineon Technologies AG 2009.
All Rights Reserved.
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Application Note No. 113
Application Note No. 113
Revision History: 2007-08-30, Rev. 1.2
Previous Version: 2005-01-14, Rev. 1.1
Page
Subjects (major changes since last revision)
All
Change of layout
Application Note
3
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
1
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4
GHz to 6 GHz inclusive, using the Ultra Low Noise BFR740L3
SiGe:C Transistor
Applications
•
2.4 GHz + 5 GHz ISM Band, UWB, etc. including 802.11 b/g WLAN, 2.4 and 5 GHz Cordless Phones,
"SDARS" Satellite - based Radio (2.33 and 2.6 GHz), etc.
Overview
•
•
The Silicon-Germanium BFR740L3 B7HFe Ultra-Low-Noise RF Transistor is shown in a simple, low-cost
general-purpose wideband LNA application."0201" case size passive components are used to reduce
occupied PCB area.
The BFR740L3 TSLP-3-4 package is only 1 x 0.6 x 0.4 mm, and is suitable for use in modules. The complete
amplifier only uses 16 mm² of PCB area.
Principal Advantages
•
•
The remarkable gain-bandwidth product & extremely low noise figure of the BFR740L3 opens up entirely new
possibilities for the RF circuit designer. In this case, simple resistive feedback is used to create a forgiving, lowparts-count, easy-to-use broadband LNA with gain & noise performance on par with traditional, more
troublesome, narrow-band LNA designs. Use of feedback yields 1) good wideband impedance match & 2)
stabilizes the amplifier.
Achieved ≅ 16.1 to 10.2 dB gain, 1.1 to 1.4 dB Noise Figure from under 1 GHz to 6 GHz, from 3.0 V supply
drawing 13.3 mA. Noise figure result does NOT "back out" FR4 PCB losses - if PCB loss at LNA input were
extracted, Noise Figure result would be approximately 0.1 - 0.2 dB lower. Input 3rd Order Intercept = +2.0 dBm
@ 2450 MHz and +10.1 dBm @ 5400 MHz
PC Board Cross Sectional Diagram
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Figure 1
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Application Note
4
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
Summary of Data
(T =25 °C, Network Analyzer Source Power = -30 dBm)
Table 1
Summary of Data
Parameter
Result
Frequency Range
Under 2 GHz to over 6 GHz, inclusive Wideband, simple, forgiving design
e.g. “universal dual-band LNA” for 2.4
and 5 GHz ISM bands
DC Current
13.13 mA @ 3.0 V
Note power supply voltage is
measured directly across PCB supply
line and ground, to eliminate voltage
drop across wire harness!
DC Voltage, VCC
3.0 V
Target not specified by customer
Gain
16.1 dB @ 2400 MHz
15.9 dB @ 2483 MHz
11.1 dB @ 5150 MHz
10.2 dB @ 5825 MHz
Useable gain from below 2 GHz to
6 GHz
Noise Figure
(These values do NOT extract
PCB losses, etc. resulting from
FR4 board and passives used on
PCB - these results are at input
SMA connector
1.2 dB @ 2450 MHz
1.3 dB @ 5150 MHz
1.4 dB @ 6000 MHz
1.5 dB @ 7000 MHz
Target: < 2 dB for entire 2 GHz 6 GHz bandwidth. See noise figure
plots and tabular data, pages 7 - 12
Input P1dB
-9.4 dBm @ 2450 MHz
See page 16
Output P1dB
+5.6 dBm @ 2450 MHz
See page 16
Input 3rd Order Intercept
+2.0 dBm @ 2450 MHz
+10.1 dBm @ 5400 MHz
See pages 23- 26
Note: IP3 can be improved by 8 to
10 dB by adding charge storage to
base, coupled in with an RF choke.
Requires the addition of 1 more chip
coil.
Output 3rd Order Intercept
+18.0 dBm @ 2450 MHz
+20.7 dBm @ 5400 MHz
See pages 23 - 26
Input Return Loss
18.7 dB @ 2400 MHz
19.4 dB @ 2483 MHz
26.4 dB @ 5150 MHz
20.7 dB @ 5825 MHz
Target: 10 dB minimum
Output Return Loss
9.9 dB @ 2400 MHz
9.9 dB @ 2483 MHz
8.9 dB @ 5150 MHz
9.8 dB @ 5825 MHz
Target: 10 dB minimum
Needs more work.
Reverse Isolation
19.7 dB @ 2400 MHz
19.6 dB @ 2483 MHz
15.1 dB @ 5150 MHz
14.1 dB @ 5825 MHz
No target specified
Application Note
Comments
5
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
Schematic Diagram
Total Parts Count = 10, including BFR740L3 Ultra Low Noise SiGe Transistor.
Note: simple, forgiving, low-cost configuration
9 FF 9
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Figure 2
Schematic Diagram
Application Note
6
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
Noise Figure, Plot, 1 to 4 GHz. Center of Plot (x-axis) is 2500 MHz.
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Figure 3
Plot of Noise Figure (1 - 4 GHz)
Application Note
7
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
Noise Figure, Tabular Data
1 GHz - 4 GHz
From Rhode & Schwarz FSEK3 + FSEM30
System Preamplifier = MITEQ SMC-02
Table 2
Noise Figure (1 - 4 GHz)
Frequency
Noise Figure
Temp
1000 MHz
1.15 dB
87.7 K
1050 MHz
1.13 dB
85.9 K
1100 MHz
1.12 dB
84.9 K
1150 MHz
1.14 dB
87.0 K
1200 MHz
1.17 dB
89.6 K
1250 MHz
1.17 dB
89.6 K
1300 MHz
1.16 dB
88.7 K
1350 MHz
1.17 dB
89.6 K
1400 MHz
1.18 dB
90.6 K
1450 MHz
1.17 dB
89.3 K
1500 MHz
1.18 dB
90.4 K
1550 MHz
1.14 dB
87.3 K
1600 MHz
1.14 dB
86.9 K
1650 MHz
1.17 dB
89.5 K
1700 MHz
1.16 dB
88.4 K
1750 MHz
1.16 dB
88.8 K
1800 MHz
1.19 dB
91.8 K
1850 MHz
1.23 dB
95.3 K
1900 MHz
1.22 dB
94.4 K
1950 MHz
1.23 dB
95.4 K
2000 MHz
1.27 dB
98.2 K
2050 MHz
1.25 dB
96.6 K
2100 MHz
1.26 dB
98.0 K
2150 MHz
1.25 dB
96.7 K
2200 MHz
1.22 dB
93.6 K
2250 MHz
1.23 dB
95.3 K
2300 MHz
1.22 dB
94.1 K
2350 MHz
1.24 dB
96.1 K
2400 MHz
1.21 dB
93.1 K
2450 MHz
1.23 dB
94.7 K
2500 MHz
1.22 dB
94.2 K
2550 MHz
1.21 dB
93.5 K
2600 MHz
1.21 dB
93.2 K
2650 MHz
1.21 dB
93.5 K
2700 MHz
1.24 dB
96.3 K
2750 MHz
1.20 dB
92.5 K
Application Note
8
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
Table 2
Noise Figure (1 - 4 GHz) (cont’d)
Frequency
Noise Figure
Temp
2800 MHz
1.22 dB
93.9 K
2850 MHz
1.22 dB
94.2 K
2900 MHz
1.22 dB
94.3 K
2950 MHz
1.21 dB
92.9 K
3000 MHz
1.20 dB
92.7 K
3050 MHz
1.17 dB
90.1 K
3100 MHz
1.22 dB
94.2 K
3150 MHz
1.22 dB
94.0 K
3200 MHz
1.19 dB
91.2 K
3250 MHz
1.20 dB
91.9 K
3300 MHz
1.24 dB
95.6 K
3350 MHz
1.21 dB
93.4 K
3400 MHz
1.23 dB
95.4 K
3450 MHz
1.24 dB
96.0 K
3500 MHz
1.25 dB
97.1 K
3550 MHz
1.24 dB
96.1 K
3600 MHz
1.28 dB
99.0 K
3650 MHz
1.27 dB
98.7 K
3700 MHz
1.28 dB
99.6 K
3750 MHz
1.28 dB
99.8 K
3800 MHz
1.32 dB
102.7 K
3850 MHz
1.31 dB
102.0 K
3900 MHz
1.31 dB
102.1 K
3950 MHz
1.32 dB
102.8 K
4000 MHz
1.34 dB
105.1 K
Application Note
9
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
Noise Figure, Plot, 4 to 7 GHz. Center of Plot (x-axis) is 5500 MHz.
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Figure 4
Plot of Noise Figure (4 - 7 GHz)
Application Note
10
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
Noise Figure, Tabular Data
4 GHz - 7 GHz
From Rhode & Schwarz FSEK3 + FSEM30
System Preamplifier = MITEQ AFS-040000800-10-ULN
Table 3
Noise Figure (4 - 7 GHz)
Frequency
Gain
Noise Figure
Temp
4000 MHz
12.31 dB
1.29 dB
100.1 K
4050 MHz
12.34 dB
1.30 dB
101.1 K
4100 MHz
12.32 dB
1.28 dB
99.3 K
4150 MHz
12.21 dB
1.29 dB
100.4 K
4200 MHz
12.33 dB
1.30 dB
101.2 K
4250 MHz
12.24 dB
1.32 dB
102.9 K
4300 MHz
12.08 dB
1.31 dB
102.4 K
4350 MHz
12.04 dB
1.28 dB
99.6 K
4400 MHz
12.03 dB
1.32 dB
103.2 K
4450 MHz
11.93 dB
1.35 dB
105.4 K
4500 MHz
11.90 dB
1.34 dB
104.6 K
4550 MHz
11.71 dB
1.35 dB
105.8 K
4600 MHz
11.67 dB
1.33 dB
103.9 K
4650 MHz
11.51 dB
1.30 dB
100.8 K
4700 MHz
11.26 dB
1.33 dB
104.2 K
4750 MHz
11.16 dB
1.31 dB
101.8 K
4800 MHz
10.93 dB
1.33 dB
103.8 K
4850 MHz
10.93 dB
1.32 dB
102.8 K
4900 MHz
10.59 dB
1.32 dB
103.4 K
4950 MHz
10.41 dB
1.31 dB
101.8 K
5000 MHz
10.37 dB
1.30 dB
101.3 K
5050 MHz
10.25 dB
1.34 dB
105.0 K
5100 MHz
10.14 dB
1.31 dB
102.4 K
5150 MHz
10.08 dB
1.29 dB
100.7 K
5200 MHz
10.07 dB
1.31 dB
102.0 K
5250 MHz
9.97 dB
1.30 dB
100.9 K
5300 MHz
9.99 dB
1.30 dB
101.5 K
5350 MHz
10.07 dB
1.27 dB
98.2 K
5400 MHz
10.03 dB
1.30 dB
101.1 K
5450 MHz
10.19 dB
1.31 dB
102.0 K
5500 MHz
10.24 dB
1.31 dB
102.2 K
5550 MHz
10.44 dB
1.30 dB
101.5 K
5600 MHz
10.41 dB
1.32 dB
103.0 K
5650 MHz
10.49 dB
1.33 dB
103.5 K
5700 MHz
10.54 dB
1.34 dB
104.6 K
5750 MHz
10.71 dB
1.34 dB
104.9 K
Application Note
11
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
Table 3
Noise Figure (4 - 7 GHz) (cont’d)
Frequency
Gain
Noise Figure
Temp
5800 MHz
10.60 dB
1.36 dB
106.6 K
5850 MHz
10.69 dB
1.38 dB
108.5 K
5900 MHz
10.58 dB
1.36 dB
106.9 K
5950 MHz
10.34 dB
1.39 dB
109.2 K
6000 MHz
10.18 dB
1.40 dB
110.1 K
6050 MHz
10.00 dB
1.40 dB
110.3 K
6100 MHz
9.80 dB
1.42 dB
111.9 K
6150 MHz
9.55 dB
1.44 dB
114.0 K
6200 MHz
9.36 dB
1.41 dB
111.6 K
6250 MHz
9.08 dB
1.43 dB
113.0 K
6300 MHz
8.84 dB
1.45 dB
114.9 K
6350 MHz
8.69 dB
1.46 dB
115.5 K
6400 MHz
8.16 dB
1.43 dB
112.9 K
6450 MHz
8.19 dB
1.42 dB
111.8 K
6500 MHz
7.88 dB
1.43 dB
112.9 K
6550 MHz
7.77 dB
1.41 dB
111.3 K
6600 MHz
7.62 dB
1.41 dB
111.2 K
6650 MHz
7.63 dB
1.42 dB
112.1 K
6700 MHz
7.59 dB
1.42 dB
112.5 K
6750 MHz
7.67 dB
1.41 dB
111.4 K
6800 MHz
7.73 dB
1.42 dB
111.8 K
6850 MHz
7.91 dB
1.46 dB
116.2 K
6900 MHz
7.97 dB
1.46 dB
115.4 K
6950 MHz
8.15 dB
1.45 dB
115.0 K
7000 MHz
8.15 dB
1.48 dB
118.0 K
Application Note
12
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
Scanned Image of PC Board
Figure 5
Image of PC Board
Application Note
13
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
Scanned Image of PC Board, Close-In Shot
Note: use of “0201” case size components
Total PCB area used ≅ 16.3 mm²
Figure 6
Image of PC Board, Close-In Shot
Application Note
14
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
Stabilty Factor “K” from 5 MHz to 8 GHz
Taken directly from Rohde and Schwarz ZVC network analyzer, as network analyzer measures demo board.
Note: K>1 except at 2.48 GHz, where K=0.993 (nearly 1). Amplifier is unconditionally stable, for all practical
purposes.
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Application Note
15
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
Amplifier Gain Compression Test @ 2450 MHz
Agilent 8720ES Network Analyzer is set to "CW" mode - e.g. set to a single frequency, with power sweep. Input
power is swept from -35 dBm to -4 dBm at 2450 MHz. Amplifier hits Input 1 dB compression point (IP1dB) at
-9.4 dBm input power. The compression point could be increased by increasing BFR740L3 current. DC current is
set to 13.5 mA however BFR740L3 can safely handle up to 50 mA.
Output P1dB = -9.4 dBm + (Gain - 1 dB) = -9.4 dBm + 15 dB =>+5.6 dBm @ 2450 MHz
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Gain Compression Test @ 2450 MHz
Application Note
16
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
Input Return Loss, Log Mag
5 MHz to 8 GHz
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Application Note
17
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
Input Return Loss, Smith Chart
Reference Plane = Input SMA Connector on PC Board
5 MHz to 8 GHz
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Application Note
18
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
Forward Gain, Wide Sweep
5 MHz to 8 GHz
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Application Note
19
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
Reverse Isolation
5 MHz to 8 GHz
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Application Note
20
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
Output Return Loss, Log Mag
5 MHz to 8 GHz
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Plot of Output Return Loss (5 MHz - 8 GHz)
Application Note
21
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
Output Return Loss, Smith Chart
Reference Plane = Output SMA Connector on PC Board
5 MHz to 8 GHz
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Figure 14
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6723 *+]
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Smith Chart of Output Return Loss (5 MHz - 8 GHz)
Application Note
22
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
Input Stimulus for Amplifier Two-Tone Test, 2450 MHz
f1 = 2449 MHz, f2 = 2450 MHz, -20 dB each tone
$1BSORWBWZRBWRQHBLQSXWBYVG
Figure 15
Input Stimulus, Tow-Tone Test @ 2450 MHz
Application Note
23
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
LNA Response to Two-Tone Test, 2450 MHz
Input IP3 = -20 + (44.0 / 2) = +2.0 dBm
Output IP3 = +2.0 dBm + 16 dB gain = +18.0 dBm
Note: Third Order Intercept could be improved by 8 - 10 dB by using charge storage off of base of transistor. This
approach would require the addition of one more “RF choke” inductor to the circuit.
$1BSORWBWZRBWRQHBUHVSRQVHBYVG
Figure 16
LNA Response, Tow-Tone Test @ 2450 MHz
Application Note
24
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
Input Stimulus for Amplifier Two-Tone Test, 5400 MHz
f1 = 5399 MHz, f2 = 5400 MHz, -15 dB each tone
$1BSORWBWZRBWRQHBLQSXWBYVG
Figure 17
Input Stimulus, Tow-Tone Test @ 5400 MHz
Application Note
25
Rev. 1.2, 2007-08-30
Application Note No. 113
Dual-Band / Broadband Feedback Low Noise Amplifier for < 2.4 GHz to 6 GHz
LNA Response to Two-Tone Test, 5400 MHz
Input IP3 = -15 + (50.2 / 2) = +10.1 dBm
Output IP3 = +10.1 dBm + 10.6 dB gain = +20.7 dBm
Note: Third Order Intercept could be improved by 8 - 10 dB by using charge storage off of base of transistor. This
approach would require the additon of one more inductor to the circuit.
$1BSORWBWZRBWRQHBUHVSRQVHBYVG
Figure 18
LNA Response, Tow-Tone Test @ 5400 MHz
Application Note
26
Rev. 1.2, 2007-08-30