19-0797; Rev 2; 9/09
KIT
ATION
EVALU
BLE
AVAILA
GPS/GNSS Low-Noise Amplifier
General Description
Features
o
High-Power Gain: 20.5dB
o
Ultra-Low-Noise Figure: 0.8dB
o
Integrated 50Ω Output Matching Circuit
o
Low Supply Current: 4.1mA
o
Wide Supply Voltage Range: 1.6V to 3.3V
o
Low Bill of Materials
o
Small Footprint: 1.5mm x 1.0mm
o
Thin Profile: 0.75mm
o
Lead-Free and RoHS-Compliant Package
MAX2659
The MAX2659 high-gain, low-noise amplifier (LNA) is
designed for GPS, Galileo, and GLONASS applications.
Designed in Maxim’s advanced SiGe process, the
device achieves a 20.5dB gain and an ultra-low-noise
figure of 0.8dB while maximizing the input-referred 1dB
compression point and the 3rd-order intercept point at
-12dBm and -5dBm, respectively.
The MAX2659 operates from a +1.6V to +3.3V single
supply and consumes only 4.1mA. The shutdown fea-
ture in the device reduces the supply current to be less
than 1µA. The MAX2659 is available in a very small,
lead-free, RoHS-compliant, 1.5mm x 1.0mm x 0.75mm,
6-pin µDFN package.
.
Automotive Navigation
Location-Enabled Mobile Devices
Telematics (Asset Tracking and Management)
Personal Navigation Device (PND)
Cellular Phones with GPS
Notebook PC/Ultra-Mobile PC
Recreational, Marine Navigation
Avionics
Applications
Ordering Information
PART
MAX2659ELT+
TEMP RANGE
-40°C to +85°C
PIN-PACKAGE
6 μDFN
6 μDFN
MAX2659ELT/V+
-40°C to +85°C
+Denotes
a lead-free package.
/V denotes an automotive qualified part.
Pin Diagram/Functional Diagram/Typical Application Circuit
+
MAX2659
GND
RFOUT
RF
OUTPUT
1
6
GND
2
5
SHDN
V
CC
LOGIC
CONTROL
RF
INPUT
C1
RFIN
3
L1
BIAS
4
V
CC
C2
L1 = 6.8nH
C1 = 470pF
C2 = 33nF
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
GPS/GNSS Low-Noise Amplifier
MAX2659
ABSOLUTE MAXIMUM RATINGS
V
CC
to GND ...........................................................-0.3V to +4.2V
Other Pins to GND....................-0.3V to + Operating V
CC
+ 0.3V
Maximum RF Input Power .............................................+10dBm
Continuous Power Dissipation (T
A
= +70°C)
6-Pin µDFN (derates 2.1mW/°C above +70°C)............167mW
CAUTION!
ESD SENSITIVE DEVICE
Operating Temperature Range ...........................-40°C to +85°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +160°C
Lead Temperature (soldering, 10s) .................................+260°C
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
DC ELECTRICAL CHARACTERISTICS
(MAX2659 EV kit; V
CC
= 1.6V to 3.3V, T
A
= -40°C to +85°C, no RF signals are applied. Typical values are at V
CC
= 2.85V and
T
A
= +25°C, unless otherwise noted.) (Note 1)
PARAMETER
Supply Voltage
Supply Current
Digital Input-Logic High
Digital Input-Logic Low
Digital Input Current
RFIN DC Voltage
SHDN
= high
0.83
SHDN
= high
Shutdown mode,
SHDN
= low
1.1
0.4
1
CONDITIONS
MIN
1.6
TYP
2.85
4.1
MAX
3.3
5.6
1
UNITS
V
mA
μA
V
V
μA
V
AC ELECTRICAL CHARACTERISTICS
(MAX2659 EV kit; V
CC
= 1.6V to 3.3V, T
A
= -40°C to +85°C, f
RFIN
= 1575.42MHz. Typical values are at V
CC
= 2.85V and T
A
= +25°C,
unless otherwise noted.) (Note 1)
PARAMETER
RF Frequency
Power Gain
Noise Figure
3rd-Order Input Intercept Point
Input 1dB Compression point
Input Return Loss
Output Return Loss
Reverse Isolation
L1 band
V
CC
= 2.85V
V
CC
= 1.6V
(Note 2)
(Note 3)
(Note 4)
(Note 2)
(Note 2)
(Note 2)
10
10
17
16.5
CONDITIONS
MIN
TYP
1575.42
20.5
20.5
0.8
-5
-12
15
25
32
MAX
UNITS
MHz
dB
dB
dBm
dBm
dB
dB
dB
Note 1:
Min and Max limits guaranteed by test at T
A
= +25°C and guaranteed by design and characterization at T
A
= -40°C and
T
A
= +85°C.
Note 2:
Guaranteed by design and characterization.
Note 3:
Measured with the two tones located at 5MHz and 10MHz offset from the center of the GPS band with -40dBm/tone.
Note 4:
Measured with a tone located at 5MHz offset from the center of the GPS band.
2
_______________________________________________________________________________________
GPS/GNSS Low-Noise Amplifier
Typical Operating Characteristics
(MAX2659 EV kit; Typical values are at V
CC
= 2.85V, T
A
= +25°C, and f
RFIN
= 1575.42MHz, unless otherwise noted.)
SUPPLY CURRENT vs. SUPPLY VOLTAGE
MAX2659 toc01
MAX2659
GAIN vs. RF FREQUENCY
MAX2659 toc02
GAIN vs. SUPPLY VOLTAGE
MAX2659 toc03
4.5
+85°C
4.3
SUPPLY CURRENT (mA)
25
20
15
GAIN (dB)
21.0
20.8
+25°C
3.9
-40°C
3.7
10
5
0
GAIN (dB)
500 750 1000 1250 1500 1750 2000 2250 2500
RF FREQUENCY (MHz)
4.1
20.6
20.4
20.2
-5
3.5
1.6 1.8 2.0
2.2 2.4 2.6
2.8
3.0 3.2 3.4
SUPPLY VOLTAGE (V)
-10
20.0
1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0 3.2 3.4
SUPPLY VOLTAGE (V)
NOISE FIGURE vs. TEMPERATURE
MAX2659 toc04
NOISE FIGURE vs. SUPPLY VOLTAGE
MAX2659 toc05
INPUT RETURN LOSS
vs. RF FREQUENCY
MAX2659 toc06
1.2
1.0
NOISE FIGURE (dB)
0.8
0.6
0.4
0.2
0
-40
-15
10
35
60
1.2
1.0
NOISE FIGURE (dB)
0.8
0.6
0.4
0.2
0
0
INPUT RETURN LOSS |S11| (dB)
-5
-10
-15
-20
-25
-30
85
1.6 1.8 2.0 2.2 2.4 2.6 2.8
SUPPLY VOLTAGE (V)
3.0 3.2 3.4
500 750 1000 1250 1500 1750 2000 2250 2500
RF FREQUENCY (MHz)
TEMPERATURE (°C)
OUTPUT RETURN LOSS
vs. RF FREQUENCY
MAX2659 toc07
REVERSE ISOLATION
vs. RF FREQUENCY
MAX2659 toc08
IIP3 vs. TEMPERATURE
TWO TONES LOCATED AT 5MHz AND
10MHz OFFSET WITH -40dBm/TONE
MAX2659 toc09
0
OUTPUT RETURN LOSS |S22| (dB)
-5
-10
-15
-20
-25
-30
-35
-40
-45
-20
-30
-40
-3.5
-4.0
-4.5
IIP3 (dBm)
-5.0
-5.5
-6.0
-6.5
REVERSE ISOLATION |S12| (dB)
-50
-60
-70
-80
500 750 1000 1250 1500 1750 2000 2250 2500
RF FREQUENCY (MHz)
500 750 1000 1250 1500 1750 2000 2250 2500
RF FREQUENCY (MHz)
-40
-15
10
35
60
85
TEMPERATURE (°C)
_______________________________________________________________________________________
3
GPS/GNSS Low-Noise Amplifier
MAX2659
Typical Operating Characteristics (continued)
(MAX2659 EV kit; Typical values are at V
CC
= 2.85V, T
A
= +25°C, and f
RFIN
= 1575.42MHz, unless otherwise noted.)
INPUT P1dB COMPRESSION
vs. TEMPERATURE
MAX2659 toc10
MAX2659 toc11
IIP3 vs. SUPPLY VOLTAGE
-3
TWO TONES LOCATED AT 5MHz AND
10MHz OFFSET WITH -40dBm/TONE
-4
-9
-10
P1dB COMPRESSION (dBm)
-11
-12
-13
-14
-15
1.6 1.8 2.0 2.2 2.4 2.6 2.8
SUPPLY VOLTAGE (V)
3.0 3.2 3.4
-40
IIP3 (dBm)
-5
-6
-7
-8
-15
10
35
60
85
TEMPERATURE (°C)
INPUT P1dB COMPRESSION
vs. SUPPLY VOLTAGE
MAX2659 toc12
INPUT P1dB COMPRESSION
vs. JAMMER FREQUENCY
MAX2659 toc13
-8
-10
P1dB COMPRESSION (dBm)
-12
-14
-16
-18
-20
0
-5
P1dB COMPRESSION (dBm)
-10
-15
-20
-25
-30
1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0 3.2 3.4
SUPPLY VOLTAGE (V)
500 750 1000 1250 1500 1750 2000 2250 2500
JAMMER FREQUENCY (MHz)
NF vs. JAMMER POWER AT 850MHz
MAX2659 toc14
NF vs. JAMMER POWER AT 1850MHz
MAX2659 toc15
3.5
3.0
2.5
NF (dB)
2.0
1.5
1.0
0.5
0
-30
-25
-20
-15
-10
3.5
3.0
2.5
NF (dB)
2.0
1.5
1.0
0.5
0
-5
-30
-25
-20
-15
-10
JAMMER POWER (dBm)
JAMMER POWER (dBm)
4
_______________________________________________________________________________________
GPS/GNSS Low-Noise Amplifier
Pin Description
PIN
1, 2
3
4
5
6
NAME
GND
RFIN
V
CC
SHDN
RFOUT
Ground. Connect to the PCB ground plane.
RF Input. Requires a DC-blocking capacitor and external matching components.
Supply Voltage. Bypass to ground with a 33nF capacitor as close as possible to the IC.
Shutdown Input. A logic-low disables the device.
RF Output. RFOUT is internally matched to 50
and incorporates an internal DC-blocking capacitor.
FUNCTION
MAX2659
Detailed Description
The MAX2659 is an LNA designed for GPS L1,
GALILEO, and GLONASS applications. The device fea-
tures a power-shutdown control mode to eliminate the
need for an external supply switch. The device
achieves a 20.5dB gain and an ultra-low-noise figure of
0.8dB. The MAX2659 consumes approximately 4.1mA
while providing a IP
1dB
of -12dBm and an IIP3 of -5dBm.
Shutdown
The MAX2659 includes a shutdown feature to turn off
the entire chip. Apply a logic high to
SHDN
pin to place
the part in the active mode and a logic low to place the
part in the shutdown mode.
Applications Information
A properly designed PC board (PCB) is essential to any
RF microwave circuit. Use controlled-impedance lines
on all high-frequency inputs and outputs. Bypass V
CC
with decoupling capacitors located close to the device.
For long V
CC
lines, it may be necessary to add decou-
pling capacitors. Locate these additional capacitors
further away from the device package. Proper ground-
ing of the GND pins is essential. If the PCB uses a top-
side RF ground, connect it directly to the GND pins. For
a board where the ground is not on the component
layer, connect the GND pins to the board with multiple
vias close to the package.
Input and Output Matching
The MAX2659 requires an off-chip input matching. Only
a 6.8nH inductor in series with a DC-blocking capacitor
is needed to form the input matching circuit. The
Typical Application Circuit
diagram shows the recom-
mended input-matching network. These values are
optimized for the best simultaneous gain, noise figure,
and return loss performance. Table 1 lists typical
device S11 values. The MAX2659 integrates an on-chip
output matching to 50Ω at the output, eliminating the
need for external matching components.
Table 1. Typical S11 Values
FREQUENCY (MHz)
1000
1100
1200
1300
1400
1500
1575
1600
1700
1800
1900
2000
REAL S11
-0.58
-0.68
-0.74
-0.74
-0.676
-0.56
-0.47
-0.44
-0.36
-0.3
-0.228
-0.14
IMAGINARY S11
-j0.52
-j0.356
-j0.16
j0.036
j0.22
j0.36
j0.415
j0.43
j0.467
j0.51
j0.567
j0.622
Chip Information
PROCESS: SiGe BiCMOS
Package Information
For the latest package outline information and land patterns, go
to
www.maxim-ic.com/packages.
PACKAGE TYPE
6 µDFN
PACKAGE CODE
L611-2
DOCUMENT NO.
21-0147
_______________________________________________________________________________________
5
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