Application Note No. 081
Discrete Semiconductors
AN081
1
2004-04-19
The BGA619 Silicon-Germanium High IP3 Low Noise
Amplifier in PCS Receiver Applications
Features
Easy-to-use LNA MMIC in 70 GHz f
t
SiGe technology
Tiny ,,Green" P-TSLP-7-1 package (no Lead or Halogen
compounds)
Low external component count
Integrated output DC blocking capacitor, integrated RF
choke on internal bias network
Three gain steps
Power off function
High IP3 in all modes
Applications
Low Noise Amplifier for 1900 MHz PCS wireless frontends (CDMA 2000).
Introduction
The BGA619 is an easy-to-use, low-cost Low Noise Amplifier (LNA) MMIC designed
for use in today's PCS systems which require excellent linearity in each of several gain
step modes. Based on Infineon's cost-effective 70 GHz f
T
Silicon-Germanium (SiGe)
B7HF bipolar process technology, the BGA619 offers a 1.5 dB noise figure and 14.9 dB
of gain at 1.96 GHz with a current consumption of 6.5 mA in high gain mode. BGA619
offers impressive IIP3 performance of 7 dBm in High Gain mode, particularly for a three-
gain step, low-cost, integrated MMIC.
The new LNA incorporates a 50
pre-matched output with an integrated output DC
blocking capacitor. The input is pre-matched, requiring an external DC blocking
capacitor. An integrated, on-chip inductor eliminates the need for an external RF choke
on the voltage supply pin. The operating mode of the device is determined by the voltage
at the GS-pin. An integrated on/off feature provides for low power consumption and
increased stand by time for PCS cellular handsets.
1
P-TSLP-7-1
2
3
6
5
4
7
Application Note No. 081
Discrete Semiconductors
AN081
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2004-04-19
Figure 1
BGA619's Equivalent Circuit.
Figure 2
Pin Connections
CURADJ
AI
DEG
GSTEP
AO
VCC
HG
4
5
6
3
2
1
paddle
connected to
GND
Bias/Gain Select
MG
LG
Application Note No. 081
Discrete Semiconductors
AN081
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2004-04-19
Overview
The BGA619 has three gain steps and one off-mode which are used in PCS-band
applications:
High Gain Mode
Mid Gain Mode
Low Gain Mode
OFF Mode
Mode selection is performed by applying a voltage to pin 6 (GSTEP) as described in
Table 1
. The source that generates these mode-select voltages should be able to source
or sink current. Please refer to the BGA619 datasheet for the maximum values of mode
control current.
The next table shows the measured performance of each of these gain modes. All
measurement values presented in this application note include losses of both PCB and
connectors - in other words, the reference planes used for measurements are the PCB's
RF SMA connectors. Noise figure and gain results shown here would improve by 0.2 -
0.3 dB compared to the values shown if PCB losses were extracted.
All measurements are performed at 1960 MHz and at a typical supply voltage of 2.78 V.
Table 1
Switching Modes for Gain Steps
Gain Mode
Gain Step Input Voltage
[V]
Current into
GS-pin [A]
Min
Max
typ
High Gain
2.2
2.4
65
Mid Gain
1.6
1.8
40
Low Gain
0.9
1.1
8
OFF
0.0
0.3
-35
Application Note No. 081
Discrete Semiconductors
AN081
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2004-04-19
Board Configuration
The circuit in
Figure 3
shows the board configuration for BGA619 LNA. The Bill of
materials for the application board can be found in
Table 3
.
Figure 3
PCB board configuration
Table 2
Performance Overview
Parameter
High Gain
Mode
Mid Gain
Mode
Low Gain
Mode
Supply voltage
2.78 V
2.78 V
2.78 V
Supply current
6.5 mA
4.5 mA
2.9 mA
Gain
14.9 dB
2.2 dB
-9.5 dB
Noise Figure
1.5 dB
8 dB
16 dB
Input return loss
10.5 dB
8.5 dB
12.5 dB
Output return loss
11.5 dB
13 dB
13 dB
Reverse Isolation
25 dB
21 dB
23 dB
Input 3
rd
order intercept point
7 dBm
1)
1)
-30 dBm per tone, f1=1950 MHz,
f = 1 MHz
6.5 dBm
2)
2)
-27 dBm per tone, f1=1950 MHz,
f = 1 MHz
15 dBm
3)
3)
-15 dBm per tone, f1=1950 MHz,
f = 1 MHz
Curadj, 1
AI, 2
DEG, 3
Vcc, 4
AO, 5
GSTEP, 6
GND, 7
R1
C4
C5
GS
C3
L1
C1
RFin
C2
L2
RFout
C6
Vcc
N1
Application Note No. 081
Discrete Semiconductors
AN081
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2004-04-19
Table 3
Bill of materilal
The application board is made of 3 layer FR4 material (see
Figure 4
). The top view can
be seen in
Figure 5
and the bottom view in
Figure 6
. Pictures of the board can be found
in
Figure 7
(complete board) and
Figure 8
(close-in photograph, where BGA619 and
surrounding elements can be found in detail).
Name Value
Package
Manufacturer Function
R1
15 k
0402
various
bias resistance; set device
current
L1
3.3 nH
0402
various
LF trap & input matching; L1
and C1 provide low-frequency
trap to increase input IP3
L2
4.7 nH
0402
various
output matching
C1
10 nF
0402
various
LF trap for IP3 enhancement
C2
10 pF
0402
various
output DC block; optional
because DC block is integrated
C3
10 pF
0402
various
input DC block
C4
10p
0402
various
control voltage filtering -
OPTIONAL, depends on actual
user implementation
C5
1 nF
0402
various
control voltage filtering -
OPTIONAL, depends on actual
user implementation
C6
1 nF
0402
various
supply filtering, depends on
actual user implementation
C7
0402
various
supply filtering -
OPTIONAL, depends on actual
user implementation
N1
BGA619
P-TSLP-7-1
Infineon
SiGe LNA with gain-steps
Application Note No. 081
Discrete Semiconductors
AN081
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2004-04-19
Figure 4
Application board; board construction
Figure 5
Application board; top view
Application Note No. 081
Discrete Semiconductors
AN081
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2004-04-19
Figure 6
Application board; bottom view
Figure 7
Foto of Application board
Application Note No. 081
Discrete Semiconductors
AN081
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2004-04-19
Figure 8
Scanned image of PCB, Close-In shot
Application Note No. 081
Discrete Semiconductors
AN081
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2004-04-19
The power supply connector
Figure 9
shows the pinning of the power supply connector needed for powering the test
board.
Figure 9
Power Supply Connector
For measurment graphs please refer to the next pages.
Application Note No. 081
Discrete Semiconductors
AN081
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2004-04-19
Figure 10
Noise Figure High Gain Mode
Figure 11
Gain High Gain Mode
Noise Figure NF = f(f)
V
CC
= 2.78V, I
CC
= 6.5mA
1.8
1.85
1.9
1.95
2
2.05
2.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
Frequency [GHz]
NF [dB]
Power Gain |S
21
| = f(f)
V
CC
= 2.78V, I
CC
= 6.5mA
1.8
1.85
1.9
1.95
2
2.05
2.1
14.5
14.6
14.7
14.8
14.9
15
15.1
15.2
Frequency [GHz]
Power Gain [dB]
Application Note No. 081
Discrete Semiconductors
AN081
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2004-04-19
Figure 12
Return Loss High Gain Mode
Figure 13
Reverse Isolation High Gain Mode
Matching |S
11
|, |S
22
| = f(f)
V
CC
= 2.78V, I
CC
= 6.5mA
1.8
1.85
1.9
1.95
2
2.05
2.1
-20
-18
-16
-14
-12
-10
-8
-6
-4
Frequency [GHz]
|S
11
|, |S
22
| [dB]
S
11
S
22
Reverse Isolation |S
12
| = f(f)
V
CC
= 2.78V, I
CC
= 6.5mA
1.8
1.85
1.9
1.95
2
2.05
2.1
-30
-29
-28
-27
-26
-25
-24
-23
-22
-21
-20
Frequency [GHz]
|S
12
| [dB]
Application Note No. 081
Discrete Semiconductors
AN081
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2004-04-19
Figure 14
Noise Figure Mid Gain Mode
Figure 15
Gain Mid Gain Mode
Noise Figure NF = f(f)
V
CC
= 2.78V, I
CC
= 4.5mA
1.8
1.85
1.9
1.95
2
2.05
2.1
7.6
7.7
7.8
7.9
8
8.1
8.2
8.3
8.4
Frequency [GHz]
NF [dB]
Power Gain |S
21
| = f(f)
V
CC
= 2.78V, I
CC
= 4.5mA
1.8
1.85
1.9
1.95
2
2.05
2.1
1.6
1.7
1.8
1.9
2
2.1
2.2
2.3
2.4
2.5
2.6
Frequency [GHz]
Power Gain [dB]
Application Note No. 081
Discrete Semiconductors
AN081
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2004-04-19
Figure 16
Return Loss Mid Gain Mode
Figure 17
Reverse Isolation Mid Gain Mode
Matching |S
11
|, |S
22
| = f(f)
V
CC
= 2.78V, I
CC
= 4.5mA
1.8
1.85
1.9
1.95
2
2.05
2.1
-20
-18
-16
-14
-12
-10
-8
-6
-4
Frequency [GHz]
|S
11
|, |S
22
| [dB]
S
11
S
22
Reverse Isolation |S
12
| = f(f)
V
CC
= 2.78V, I
CC
= 4.5mA
1.8
1.85
1.9
1.95
2
2.05
2.1
-25
-24
-23
-22
-21
-20
-19
-18
-17
-16
-15
Frequency [GHz]
|S
12
| [dB]
Application Note No. 081
Discrete Semiconductors
AN081
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2004-04-19
Figure 18
Noise Figure Low Gain Mode
Figure 19
Gain Low Gain Mode
Noise Figure NF = f(f)
V
CC
= 2.78V, I
CC
= 2.9mA
1.8
1.85
1.9
1.95
2
2.05
2.1
15
15.2
15.4
15.6
15.8
16
16.2
16.4
16.6
16.8
17
Frequency [GHz]
NF [dB]
Power Gain |S
21
| = f(f)
V
CC
= 2.78V, I
CC
= 2.9mA
1.8
1.85
1.9
1.95
2
2.05
2.1
-11
-10.5
-10
-9.5
-9
-8.5
-8
Frequency [GHz]
Power Gain [dB]
Application Note No. 081
Discrete Semiconductors
AN081
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2004-04-19
Figure 20
Return Loss Low Gain Mode
Figure 21
Reverse Isolation Low Gain Mode
Matching |S
11
|, |S
22
| = f(f)
V
CC
= 2.78V, I
CC
= 2.9mA
1.8
1.85
1.9
1.95
2
2.05
2.1
-20
-18
-16
-14
-12
-10
-8
-6
-4
Frequency [GHz]
|S
11
|, |S
22
| [dB]
S
11
S
22
Reverse Isolation |S
12
| = f(f)
V
CC
= 2.78V, I
CC
= 2.9mA
1.8
1.85
1.9
1.95
2
2.05
2.1
-25
-24
-23
-22
-21
-20
-19
-18
-17
-16
-15
Frequency [GHz]
|S
12
| [dB]
Application Note No. 081
Discrete Semiconductors
AN081
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2004-04-19
Application Note No. 081
Discrete Semiconductors
AN081
17
2004-04-19
For questions on technology, delivery and prices please contact the Infineon
Technologies Offices in Germany or the Infineon Technologies Companies and
Representatives worldwide: see our webpage at http://www.infineon.com
Edition 2004-04-19
Published by Infineon Technologies AG,
St.-Martin-Strasse 53,
D-81541 Mnchen
Infineon Technologies AG 1999.
All Rights Reserved.
Attention please!
The information herein is given to describe certain components and shall not be considered as warranted charac-
teristics.
Terms of delivery and rights to technical change reserved.
We hereby disclaim any and all warranties, including but not limited to warranties of non-infringement, regarding
circuits, descriptions and charts stated herein.
Infineon Technologies is an approved CECC manufacturer.
Information
For further information on technology, delivery terms and conditions and prices please contact your nearest Infi-
neon Technologies Office in Germany or our Infineon Technologies Representatives worldwide (see address list).
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.
AN081
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