MAXIM MAX2634AXT+

19-4383; Rev 1; 3/09
KIT
ATION
EVALU
E
L
B
AVAILA
315MHz/433MHz Low-Noise
Amplifier for Automotive RKE
Features
o Optimized for 308MHz, 315MHz, 418MHz,
and 433.92MHz
The MAX2634 low-noise amplifier (LNA) with low-power
shutdown mode is optimized for 315MHz and
433.92MHz automotive remote keyless entry (RKE)
applications. At 315MHz, the LNA achieves 15.5dB
power gain and a 1.25dB noise figure while only consuming 2.5mA of supply current from a 2.2V to 5.5V
power supply. An integrated logic-controlled low-power
shutdown mode reduces power consumption to 0.1µA
and replaces the two transistors typically required to
implement the shutdown function in discrete-based
RKE LNA solutions. The device further reduces component count by integrating the output matching and DCblocking components, and only requires a single
inductor to match the input for best noise figure and
input return loss.
o 2.2V to 5.5V Supply Voltage Range
o Low Operating Supply Current
2.5mA (typ), 4mA (max)
o Logic-Controlled 1µA (max) Shutdown
o Typical Performance at 315MHz
1.25dB Noise Figure
-16dBm Input IP3
15.5dB Power Gain
o Automotive Temperature Range
-40°C to +125°C
o ESD Rating of ±2.5kV (HBM) on All Pins
The device is available in a small 6-pin (2.0mm x
2.2mm x 0.9mm) lead-free SC70 package for automotive applications that require visual inspection of PCB
solder connections.
o AEC-Q100 Qualification
Ordering Information
Applications
Remote Keyless Entry (RKE)
Tire Pressure Monitoring Systems (TPMS)
Security
PART
TEMP RANGE
PINPACKAGE
TOP
MARK
MAX2634AXT+
-40°C to +125°C
6 SC70
+ADG
+Denotes a lead(Pb)-free/RoHS-compliant package.
Garage Door Openers
Pin Configuration
Telemetry Receivers
TOP VIEW
+
GND
1
SHDN
2
GND
3
MAX2634
6
RFOUT
5
VCC
4
RFIN
SC70
Functional Diagram/Typical Operating Circuit appears at
end of data sheet.
Performance Table
FREQUENCY
(MHz)
L1
(nH)
SUPPLY
CURRENT
(mA)
GAIN
(dB)
NOISE FIGURE
(dB)
INPUT P1dB
(dBm)
INPUT IP3
(dBm)
308
56
2.5
15.5
1.25
-29
-16
315
56
2.5
15.5
1.25
-29
-16
418
33
2.5
13.5
1.25
-26
-12
433.92
33
2.5
13.5
1.25
-26
-12
________________________________________________________________ Maxim Integrated Products
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.
1
MAX2634
General Description
MAX2634
315MHz/433MHz Low-Noise
Amplifier for Automotive RKE
ABSOLUTE MAXIMUM RATINGS
VCC Pin to GND .....................................................-0.3V to +6.0V
RFIN.................Pin Must Be AC-Coupled with DC-Blocking Cap
RFOUT, SHDN............................................-0.3V to (VCC + 0.3V)
RF Input Power .................................................................+5dBm
Continuous Power Dissipation (TA = +70°C)
6-Pin SC70 (derate 3.1mW/°C above +70°C) ..............245mW
Junction-to-Case Thermal Resistance (θJC)
(Note 1) ......................................................................115°C/W
Junction-to-Ambient Thermal Resistance (θJA)
(Note 1) ......................................................................326°C/W
Operating Temperature Range .........................-40°C to +125°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +160°C
Lead Temperature (soldering, 10s)....................................300°C
Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a 4-layer
board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial.
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.
CAUTION! ESD SENSITIVE DEVICE
DC ELECTRICAL CHARACTERISTICS
(VCC = +2.2V to +5.5V, TA = -40°C to +125°C, Typical values are at VCC = +3.0V, TA = +25°C, unless otherwise noted. RFIN and
RFOUT are AC-coupled and terminated to 50Ω. No RF input signals at RFIN and RFOUT.) (Note 2)
PARAMETER
CONDITIONS
Operating Supply Voltage
Operating Supply Current
Shutdown Supply Current
MIN
TYP
2.2
MAX
UNITS
5.5
V
4
mA
6
mA
VSHDN = 0, TA = +25°C
1
µA
VSHDN = 0, TA = -40°C to +125°C
10
µA
SHDN = high, TA = +25°C
2.5
SHDN = high, TA = -40°C to +125°C
DIGITAL CONTROL INPUTS (SHDN)
Digital Input-Voltage High
1.1
V
Digital Input-Voltage Low
0.4
V
Digital Input-Current High
VSHDN = VIH
5
µA
Digital Input-Current Low
VSHDN = VIL
1
µA
SHUTDOWN MODE CONTROL
Enable Time
130
µs
Disable Time
20
µs
2
_______________________________________________________________________________________
315MHz/433MHz Low-Noise
Amplifier for Automotive RKE
(MAX2634 EV Kit, VCC = +2.2V to +5.5V, TA = -40°C to +125°C. Typical values are at VCC = +3.0V and TA = +25°C, unless otherwise
noted. PRFIN = -40dBm, SHDN = high.) (Note 2)
PARAMETER
CONDITIONS
MIN
TYP
TA = +25°C
12.5
15.5
TA = -40°C to +125°C, VCC = +3.0V
11.5
MAX
UNITS
fRFIN = 315MHz
Power Gain
Noise Figure
TA = +25°C
Input Third-Order Intercept Point
(Note 3)
dB
1.25
dB
-16
dBm
Input 1dB Compression Point
-29
dBm
Input Return Loss
10
dB
Output Return Loss
8
dB
Reverse Isolation
60
dB
fRFIN = 433.92MHz
Power Gain
TA = +25°C (Note 4)
11
TA = -40°C to +125°C, VCC = +3.0V (Note 4)
10
Noise Figure
TA = +25°C
Input Third-Order Intercept Point
(Note 3)
13.5
dB
1.25
dB
-12
dBm
Input 1dB Compression Point
-26
dBm
Input Return Loss
11
dB
Output Return Loss
8
dB
Reverse Isolation
60
dB
Note 2: Guaranteed by production test at TA = +25°C. Guaranteed by design and characterization at TA = -40°C and TA = +125°C.
Note 3: Measured with two tones located at 315MHz and 316MHz or 433MHz and 434MHz at -40dBm/tone.
Note 4: Guaranteed by design and characterization.
Typical Operating Characteristics
(MAX2634 EV Kit, VCC = +2.2V to +5.5V, TA = -40°C to +125°C. Typical values are at VCC = +3.0V and TA = +25°C, unless otherwise
noted. fRFIN = 315MHz/433MHz, PRFIN = -40dBm, SHDN = high.)
20
15
10
TA = +25°C
2.5
S21
5
S11, S22, S21 (dB)
10
3.0
S11
0
-5
-15
TA = -40°C
2.2
3.3
4.4
SUPPLY VOLTAGE (V)
5.5
S11
0
-5
-15
S22
S22
-20
-20
1.5
S21
5
-10
-10
2.0
MAX2634 toc03
15
S11, S22, S21 (dB)
SUPPLY CURRENT (mA)
3.5
20
MAX2634 toc02
TA = +125°C
MAX2634 toc01
4.0
S11, S22, S21 vs. FREQUENCY
(433MHz)
S11, S22, S21 vs. FREQUENCY
(315MHz)
SUPPLY CURRENT vs. SUPPLY VOLTAGE
200
300
400
500
FREQUENCY (MHz)
600
200
300
400
500
FREQUENCY (MHz)
_______________________________________________________________________________________
600
3
MAX2634
AC ELECTRICAL CHARACTERISTICS
Typical Operating Characteristics (contineed)
(MAX2634 EV Kit, VCC = +2.2V to +5.5V, TA = -40°C to +125°C. Typical values are at VCC = +3.0V and TA = +25°C, unless otherwise
noted. fRFIN = 315MHz/433MHz, PRFIN = -40dBm, SHDN = high.)
NOISE FIGURE vs. SUPPLY VOLTAGE
(433MHz)
IIP3 vs. SUPPLY VOLTAGE
(433MHz)
2.5
-8
TA = +125°C
2.0
-16
TA = -40°C
-18
-11
-14
-17
TA = +25°C
1.5
1.0
0.5
TA = -40°C
-20
TA = -40°C
-20
3
4
5
SUPPLY VOLTAGE (V)
6
0
2
3
NOISE FIGURE vs. SUPPLY VOLTAGE
(315MHz)
4
5
SUPPLY VOLTAGE (V)
6
2
2.0
16
TA = +25°C
15
GAIN (dB)
1.5
1.0
TA = +25°C
TA = -40°C
15
TA = -40°C
14
0
4
5
SUPPLY VOLTAGE (V)
6
11
2
3
4
5
SUPPLY VOLTAGE (V)
2
6
OUTPUT POWER (dBm)
-50
-60
1AVG
-70
-80
-90
fRFIN = 315MHz
PRFIN = -43dBm
-40
-50
-60
-70
-80
1AVG
-90
-100
-100
-110
-110
-120
-120
0
20 40 60 80 100 120 140 160 180 200
TIME (µs)
4
-30
OUTPUT POWER (dBm)
fRFIN = 315MHz
PRFIN = -43dBm
-40
4
5
SUPPLY VOLTAGE (V)
-20
MAX2634 toc10
-30
3
SHUTDOWN TIME
TURN-ON TIME
-20
TA = +125°C
12
TA = +125°C
11
3
14
13
12
TA = -40°C
TA = +25°C
16
13
0.5
6
17
MAX2634 toc08
TA = +125°C
4
5
SUPPLY VOLTAGE (V)
GAIN vs. SUPPLY VOLTAGE
(315MHz)
17
MAX2634 toc07
2.5
2
3
GAIN vs. SUPPLY VOLTAGE
(433MHz)
GAIN (dB)
2
MAX2634 toc09
TA = +25°C
IIP3 (dBm)
IIP3 (dBm)
TA = +25°C
-14
MAX2634 toc11
-12
TA = +125°C
NOISE FIGURE (dB)
TA = +125°C
MAX2634 toc05
-5
MAX2634 toc04
-10
MAX2634 toc06
IIP3 vs. SUPPLY VOLTAGE
(315MHz)
NOISE FIGURE (dB)
MAX2634
315MHz/433MHz Low-Noise
Amplifier for Automotive RKE
0
5
10 15 20 25 30 35 40 45 50
TIME (µs)
_______________________________________________________________________________________
6
315MHz/433MHz Low-Noise
Amplifier for Automotive RKE
PIN
NAME
1, 3
GND
Ground. Use minimum path to ground plane to minimize inductance.
FUNCTION
2
SHDN
Shutdown Input. A logic-level high enables the LNA, and a logic-level low disables the LNA.
4
RFIN
RF Input. Requires an inductor to match the input for best noise figure and return loss. A DC-blocking
capacitor is required if the RFIN input will see a DC voltage or ground. See the Functional
Diagram/Typical Operating Circuit.
5
VCC
Supply Voltage. Bypass to ground with a 0.01µF capacitor as close as possible to the pin.
6
RFOUT
RF Output. Internally matched to 50 and incorporates an internal DC-blocking capacitor.
Table 1. Typical Input and Output Impedances in R+jX Format
(VCC = +3.0V, TA = +25°C.)
FREQUENCY (MHz)
100
INPUT IMPEDANCE
OUTPUT IMPEDANCE
R
X
R
X
58
-438
92
-94
200
43
-216
92.1
-50
308
29
-139
91.2
-35.8
315
29.4
-137
91
-35
418
29.2
-101
90.5
-30
434
28.5
-96
89.5
-29.3
500
26.4
-83
91
-28.2
600
26.7
-69
87.5
-27.3
Detailed Description
The MAX2634 LNA with low-power shutdown mode is
optimized for 308MHz, 315MHz, 418MHz, and 433MHz
automotive RKE applications, which are required to
operate over the -40°C to +125°C automotive temperature range. The device reduces component count by
integrating the output matching and DC-blocking components, and only requires a single inductor to match
the input for best noise figure and input return loss. An
integrated logic-controlled low-power shutdown mode
reduces power consumption to 0.1µA and replaces the
two transistors typically required to implement the shutdown function in discrete-based RKE LNA solutions.
Input Matching
The MAX2634 requires an off-chip input matching network. The Functional Diagram/Typical Operating Circuit
shows the recommended input-matching network component values for operation at 315MHz and 433MHz.
These values are optimized for the best simultaneous
gain, noise figure, and return loss performance. Table 1
lists typical input and output impedances.
_______________________________________________________________________________________
5
MAX2634
Pin Description
MAX2634
315MHz/433MHz Low-Noise
Amplifier for Automotive RKE
RF Input Coupling Capacitor
Input IP3 vs. Enable Time
The value of the coupling capacitor affects input IP3
and turn-on time. A larger coupling capacitor results in
higher input IP3 at the expense of longer turn-on time.
See Table 3 for the typical amount of trade-off.
Integrated Output Matching
Network and DC-Block
The MAX2634 integrates the output matching network
and DC-block, eliminating the need for external matching components while providing a broadband match.
See the Functional Diagram/Typical Operating Circuit
for component values.
Table 2. MAX2634 Typical Noise
Parameters
(VCC = +3.0V, TA = +25°C.)
|ΓOPT|
FREQUENCY
(MHz)
FMIN
(dB)
|ΓOPT|
308
0.64
0.50
27.0
9.78
315
0.65
0.49
27.7
9.78
418
0.78
0.44
37.4
9.87
434
0.80
0.44
38.9
9.88
ANGLE
RN (Ω)
Shutdown
The MAX2634 features a shutdown pin to disable the
entire chip. Apply a logic-high to the SHDN pin to place
the part in the active mode, and a logic-low to place the
part in the shutdown mode.
Power-Supply Bypassing
Bypassing the V CC line is necessary for optimum
gain/linearity performance. See the Functional
Diagram/Typical Operating Circuit for bypassing
capacitor values.
Layout Information
A properly designed PCB is essential to any RF/
microwave circuit. Use controlled-impedance lines on
all high-frequency inputs and outputs. Bypass with
decoupling capacitors located close to the device’s
VCC pin. For long VCC lines, it may be necessary to add
additional decoupling capacitors. These additional
capacitors can be located farther away from the device
package. Proper grounding of the GND pins is essential. If the PCB uses a topside RF ground, connect it
directly to all GND pins. For a board where the ground
plane is not on the component layer, the best technique
is to connect the GND pins to the board with a plated
through-hole located close to the package.
6
Table 3. RF Input Coupling Capacitor
Input IP3 vs. Enable Time
INPUT DC-BLOCKING
CAPACITOR,
C1 (nF)
ENABLE
TIME
(µs)
INPUT IP3 AT
315MHz
(dBm)
1
6
-19
3.3
20
-14
22
130
-12
100
600
-11
1000
6000
-11
Chip Information
PROCESS: SiGe BiCMOS
_______________________________________________________________________________________
315MHz/433MHz Low-Noise
Amplifier for Automotive RKE
+
GND 1
MAX2634
6 RFOUT
RF
OUTPUT
VCC
LOGIC
CONTROL
5 VCC
SHDN 2
C3
100pF
BIAS
GND
3
4 RFIN
L1*
C2
0.01µF
C1**
22nF
RF
INTPUT
*L1 = 56nH FOR 308MHz/315MHz.
*L1 = 33nH FOR 418MHz/433.92MHz.
**C1 = DC-BLOCK. OPTIONAL IF DC IS NOT APPLIED TO RFIN.
Package Information
For the latest package outline information and land patterns, go to www.maxim-ic.com/packages.
PACKAGE TYPE
PACKAGE CODE
DOCUMENT NO.
6 SC70
X6SN-1
21-0077
_______________________________________________________________________________________
7
MAX2634
Functional Diagram/Typical Operating Circuit
MAX2634
315MHz/433MHz Low-Noise
Amplifier for Automotive RKE
Revision History
REVISION
NUMBER
REVISION
DATE
0
10/08
Initial release
1
3/09
Updated the Features, Performance Table, Electrical Characteristics, and
Typical Operating Characteristics sections.
DESCRIPTION
PAGES
CHANGED
—
1, 3, 4
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
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© 2009 Maxim Integrated Products
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