MAX2242

MAX2242
19-1912; Rev 3; 11/03
KIT
ATION
EVALU
E
L
B
A
IL
AVA
2.4GHz to 2.5GHz Linear Power Amplifier
________________________Applications
Features
♦ 2.4GHz to 2.5GHz Operating Range
♦ +22.5dBm Linear Output Power (ACPR of <-33dBc
1st-Side Lobe and <-55dbc 2nd-Side Lobe)
♦ 28.5dB Power Gain
♦ On-Chip Power Detector
♦ External Bias Control for Current Throttleback
♦ +2.7V to +3.6V Single-Supply Operation
♦ 0.5µA Shutdown Mode
♦ Tiny Chip-Scale Package (1.5mm ✕ 2.0mm)
Ordering Information
PART
TEMP RANGE
PINPACKAGE
TOP
MARK
MAX2242EBC-T
-40°C to +85°C
3 ✕ 4 UCSP
AAE
Pin Configuration
RF_IN
GND
VCC1
C4
B4
A4
IEEE 802.11b DSSS Radios
Wireless LANs
HomeRF
2.4GHz Cordless Phones
GND
2.4GHz ISM Radios
C3
VCCB
BIAS
CIRCUIT
A3
PD_OUT
SHDN
C2
B2
VCC2
A2
Actual Size
DET
1.5mm ✕ 2.0mm
Typical Application Circuit appears at end of data sheet.
UCSP is a trademark of Maxim Integrated Products, Inc.
C1
B1
A1
BIAS
RF_OUT
GND
3✕4 UCSP
________________________________________________________________ Maxim Integrated Products
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
1
MAX2242
General Description
The MAX2242 low-voltage linear power amplifier (PA) is
designed for 2.4GHz ISM-band wireless LAN applications. It delivers +22.5dBm of linear output power with
an adjacent-channel power ratio (ACPR) of <-33dBc
1st-side lobe and <-55dBc 2nd-side lobe, compliant
with the IEEE 802.11b 11MB/s WLAN standard with at
least 3dB margin. The PA is packaged in the tiny 3x4
chip-scale package (UCSP™), measuring only 1.5mm x
2.0mm, ideal for radios built in small PC card and compact flash card form factors.
The MAX2242 PA consists of a three-stage PA, power
detector, and power management circuitry. The power
detector provides over 20dB of dynamic range with
±0.8dB accuracy at the highest output power level. An
accurate automatic level control (ALC) function can be
easily implemented using this detector circuit.
The PA also features an external bias control pin.
Through the use of an external DAC, the current can be
throttled back at lower output power levels while maintaining sufficient ACPR performance. As a result, the
highest possible efficiency is maintained at all power
levels. The device operates over a single +2.7V to
+3.6V power-supply range. An on-chip shutdown feature reduces operating current to 0.5µA, eliminating the
need for an external supply switch.
MAX2242
2.4GHz to 2.5GHz
Linear Power Amplifier
ABSOLUTE MAXIMUM RATINGS
VCC1, VCC2 to GND (no RF signal applied) ..........-0.3V to +5.5V
RF Input Power ...............................................................+10dBm
SHDN, BIAS, PD_OUT, RF_OUT ................-0.3V to (VCC + 0.3V)
DC Input Current at RF_IN Port.............................-1mA to +1mA
Maximum VSWR Without Damage ........................................10:1
Maximum VSWR for Stable Operation.....................................5:1
Continuous Power Dissipation (TA = +85°C)
3✕4 UCSP (derate 80mW/°C above +85°C) ..................1.6W
Operating Temperature Range ...........................-40°C to +85°C
Thermal Resistance .........................................................25°C/W
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +125°C
Lead Temperature (soldering, 10s) .................................+260°C
Continuous Operating Lifetime.....................10yrs × 0.92(TA - 60°C)
(For Operating Temperature, TA ≥ +60°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.
CAUTION! ESD SENSITIVE DEVICE
DC ELECTRICAL CHARACTERISTICS
(VCC = +2.7V to +3.6V, fIN = 2.4GHz to 2.5GHz, V SHDN = VCC, RF_IN = RF_OUT = connected to 50Ω load, TA = -40°C to +85°C.
Typical values are measured at VCC = +3.3V, fIN = 2.45GHz, TA = +25°C, unless otherwise noted.) (Note 1)
PARAMETER
CONDITIONS
Supply Voltage
Supply Current
(Notes 2, 3, 6)
Shutdown Supply Current
Logic Input Voltage High
MIN
TYP
2.7
POUT = +22dBm, VCC = +3.3V, idle current = 280mA
300
POUT = +13dBm, idle current = 55mA
90
POUT = +5dBm, idle current = 25mA
50
V SHDN = 0, no RF input
0.5
UNITS
3.6
V
335
mA
10
2.0
Logic Input Voltage Low
2
MAX
µA
V
0.8
V
Logic Input Current High
-1
5
µA
Logic Input Current Low
-1
1
µA
_______________________________________________________________________________________
2.4GHz to 2.5GHz
Linear Power Amplifier
(MAX2242 Evaluation Kit, VCC = +3.3V, V SHDN = VCC, 50Ω source and load impedance, fIN = 2.45GHz, TA = +25°C, unless otherwise noted.) (Note 6)
PARAMETER
CONDITIONS
Frequency Range (Notes 3, 4)
Power Gain (Notes 1, 3)
MIN
TYP
2.4
TA = +25°C
26.5
TA = -40°C to +85°C
25.5
MAX
UNITS
2.5
GHz
28.5
dB
Gain Variation Over Temperature
(Note 3)
TA = -40°C to +85°C
±1.2
dB
Gain Variation Over VCC (±10%)
(Note 3)
VCC = +3.0V to +3.6V
±0.3
dB
Output Power (Notes 3, 5, 8)
ACPR,
1st-side lobe < -33dBc,
2nd-side lobe < -55dBc
22.5
dBm
Saturated Output Power
PIN = +5dBm
26.5
dBm
-40
dBc
Input VSWR
Over full PIN range
1.5:1
Output VSWR
Over full POUT range
2.5:1
Power Ramp Turn-On Time
(Note 7)
SHDN from low to high
1
1.5
µs
Power Ramp Turn-Off Time
(Note 7)
SHDN from high to low
1
1.5
µs
2.5
5
µs
Harmonic Output (2f, 3f, 4f)
RF Output Detector Response
TIme
Po = +22dBm (Note 9)
RF Output Detector Voltage
Note 1:
Note 2:
Note 3:
Note 4:
Note 5:
Note 6:
Note 7:
Note 8:
Note 9:
21.5
1.8
Po = +13dBm (Note 9)
0.9
Po = +5dBm (Note 9)
0.55
V
Specifications over TA = -40°C to +85°C are guaranteed by design. Production tests are performed at TA = +25°C.
Idle current is controlled by external DAC for best efficiency over the entire output power range.
Parameter measured with RF modulation based on IEEE 802.11b standard.
Power gain is guaranteed over this frequency range. Operation outside this range is possible, but is not guaranteed.
Output two-tone third-order intercept point (OIP3) is production tested at TA = +25°C. The OIP3 is tested with two signals at
f1 = 2.450GHz and f2 = 2.451GHz with fixed PIN.
Min/max limits are guaranteed by design and characterization.
The total turn-on and turn-off times required for PA output power to settle to within 0.5dB of the final value.
Excludes PC board loss of approximately 0.15dB.
See Typical Operating Characteristics for statistical variation.
_______________________________________________________________________________________
3
MAX2242
AC ELECTRICAL CHARACTERISTICS
Typical Operating Characteristics
(VCC = +3.3V, fIN = 2.45MHz, RF modulation = IEEE 802.11b, V SHDN = VCC, TA = +25°C, unless otherwise noted.)
PO = +22dBm
320
28
280
TA = -40°C
260
TA = +25°C
TA = +85°C
TA = +85°C
27
240
IDLE CURRENT SET TO 280mA
AT VCC = +3.3V, TA = +25°C
26
220
3.3
3.6
2.7
3.0
SUPPLY VOLTAGE (V)
300
IDLE CURRENT ADJUSTED TO
KEEP ACPR/ALT = -33/-55dBc
240
ICC (mA)
ACPR (dBc)
TA = -40°C
210
180
TA = +25°C
150
120
90
TA = +85°C
60
30
0
2
4
6
8 10 12 14 16 18 20 22
MAX2242 toc07
TA = +85°C
305
300
295
TA = -40°C
290
TA = -40°C
TA = +25°C
-32
POUT = +22 dBm
-35
17
18
19
20
21
22
23
2
24
25
2400
2425
2450
FREQUENCY (MHz)
1.8
1.6
1.4
1.2
1
0.8
0.4
280
2400
2425
2450
FREQUENCY (MHz)
2475
2500
5
TA = +85°C
0.6
285
3
-34
POWER DETECTOR VOLTAGE
vs. OUTPUT POWER
TA = +25°C
1
-33
ICC vs. FREQUENCY
310
-3 -1
ACPR vs. FREQUENCY
IDLE CURRENT = 280mA
OUTPUT POWER (dBm)
PO = +22dBm
-7 -5
INPUT POWER (dBm)
OUTPUT POWER (dBm)
320
315
-24
-25
-26
-27
-28
-29
-30
-31
-32
-33
-34
-35
-36
-37
-38
-39
-40
16
POWER DETECTOR VOLTAGE (V)
0
-15 -13 -11 -9
MAX2242 toc08
270
3.6
ACPR vs. OUTPUT POWER
MAX2242 toc04
ICC vs. OUTPUT POWER
330
3.3
SUPPLY VOLTAGE (V)
ACPR (dBc)
3.0
MAX2242 toc05
2.7
4
OUTPUT POWER (dBm)
29
ICC (mA)
GAIN (dB)
300
TA = +25°C
28
27
26
25
24
23
22
21
20
19
18
17
16
15
MAX2242 toc03
30
OUTPUT POWER vs. INPUT POWER
MAX2242 toc02
TA = -40°C
MAX2242 toc01
PO = +22dBm
ICC vs. SUPPLY VOLTAGE
MAX2242 toc06
GAIN vs. SUPPLY VOLTAGE
31
ICC (mA)
MAX2242
2.4GHz to 2.5GHz
Linear Power Amplifier
0
2
4
6
8 10 12 14 16 18 20 22
OUTPUT POWER (dBm)
_______________________________________________________________________________________
2475
2500
p2.4GHz to 2.5GHz
Linear Power Amplifier
SIGMA = 0.25dBm
BASED ON 100 PARTS
20
15
10
10
5
5
0
0
12.1 12.3 12.5 12.7 12.9 13.1 13.3 13.5 13.7
2.8
3.4 4.0
4.6
5.2 5.8
6.4 7.0
OUTPUT POWER (dBm)
S11, S22, vs. FREQUENCY
MAX2242
S21 vs. FREQUENCY
-5
30
PIN = -15dBm
29
S21 (dB)
S22
-7
MAX2242 toc13
PIN = -15dBm
-3
S11, S22 (dB)
2.2
OUTPUT POWER (dBm)
MAX2242 toc12
-1
SIGMA = 0.75dBm
BASED ON 100 PARTS
15
OCCURRENCES
OCCURRENCES
20
MAX2242 toc10
25
MAX2242 toc11
OUTPUT POWER HISTOGRAM AT FIXED
0.5V POWER DETECTOR VOLTAGE
OUTPUT POWER HISTOGRAM AT FIXED
0.8V POWER DETECTOR VOLTAGE
28
27
-9
-11
S11
26
-13
25
-15
2400
2420
2440
2460
FREQUENCY (MHz)
2480
2500
2400
2420
2440
2460
2480
2500
FREQUENCY (MHz)
_______________________________________________________________________________________
5
MAX2242
Typical Operating Characteristics (continued)
(VCC = +3.3V, fIN = 2.45MHz, RF modulation = IEEE 802.11b, V SHDN = VCC, TA = +25°C, unless otherwise noted.)
2.4GHz to 2.5GHz
Linear Power Amplifier
MAX2242
Pin Description
PIN
NAME
FUNCTION
A1
GND
3rd Stage Ground. Refer to Application Information section for detailed PC-board layout information.
A2
VCC2
2nd Stage Supply Voltage. Bypass to ground using configuration in the typical operating circuit.
A3
GND
3rd Stage Ground. Refer to Application Information section for detailed PC-board layout information.
A4
VCC1
1st Stage Supply Voltage. Bypass to ground using configuration in the typical operating circuit.
B1
RF_OUT
RF Output. Requires external matching.
B2
PD_OUT
Power Detector Output. This output is a DC voltage indicating the PA output power. Connect a
47kΩ resistor to GND.
B4
GND
1st Stage and Bias Control Circuit Ground
C1
BIAS
Bias Control. Connect one 8kΩ resistor from BIAS to GND and one 8kΩ resistor from BIAS to DAC
block to set the idle current.
C2
SHDN
Shutdown Input. Drive logic low to place the device in shutdown mode. Drive logic high for normal
operation.
C3
VCCB
Bias Circuit DC Supply Voltage. Bypass to ground using configuration in the typical operating
circuit.
C4
RF_IN
RF Input. Requires external matching.
Detailed Description
The MAX2242 is a linear PA intended for 2.4GHz ISMband wireless LAN applications. The PA is fully characterized in the 2.4GHz to 2.5GHz ISM band. The PA
consists of two driver stages and an output stage. The
MAX2242 also features an integrated power detector
and power shutdown control mode.
Dynamic Power Control
The MAX2242 is designed to provide optimum poweradded efficiency (PAE) in both high and low power
applications. For a +3.3V supply at high output power
level, the output power is typically +22.5dBm with an
idle current of 280mA. At low output-power levels, the
DC current can be reduced by an external DAC to
increase PAE while still maintaining sufficient ACPR
performance. This is achieved by using external resistors connected to the BIAS pin to set the bias currents
of the driver and output stages. The resistors are typically 8kΩ. Typically, a DAC voltage of 1.0V will give a
280mA bias current. Increasing the DAC voltage will
decrease the idle current. Similarly, decreasing the
DAC voltage will increase the idle current.
The BIAS pin is maintained at a constant voltage of
1.0V, allowing the user to set the desired idle current
using only two off-chip 1% resistors: a shunt resistor,
R2, from BIAS to ground; and a series resistor, R1, to
6
the DAC voltage, as shown in the Typical Application
Circuit. Resistor values R1 and R2 are determined as
follows:
VMAX = 1.0 + (1.0 ✕ R1) / R2;
(ICC = 0, VDAC = VMAX)
(1)
IMAX = (1.0 ✕ 1867) ✕ (R1 + R2) / (R1 ✕ R2);
(ICC = IMAX = max value, VDAC = 0)
(2)
IDAC = (VDAC - 1.0) / R1
(3)
IMID = (1.0 ✕ 1867) / R2;
(VDAC = 1.0V or floating)
(4)
ICC = 1867 ✕ IBIAS
(5)
where
VMAX = is the maximum DAC voltage
IMAX = is the maximum idle current
IMID = is the idle current with VDAC = 1.0V or not
connected
VDAC = is the DAC voltage
IDAC = is the DAC current
If no DAC is used and a constant idle current is
desired, use equation 4 to determine the resistor values
for a given total bias current. Only R2 is required.
_______________________________________________________________________________________
2.4GHz to 2.5GHz
Linear Power Amplifier
MAX2242
For a DAC capable of both sourcing and sinking currents, the full voltage range of the DAC (typically from 0
to +3V) can be used. By substituting the desired values
of VMAX and IMAX into equations 1 and 2, R1 and R2
can be easily calculated.
For a DAC capable of sourcing current only, use equation 4 to determine the value of resistor R2 for the
desired maximum current. Use equation 1 to determine
the value of resistor R1 for the desired minimum current.
For a DAC capable of sinking current only, set resistors
R1 and R2 to 0 and connect the DAC directly to the
BIAS pin. Use equation 5 to determine the DAC current
required for a given ICC.
Shutdown Mode
Apply logic low to SHDN (pin C2) to place the
MAX2242 into shutdown mode. In this mode, all gain
stages are disabled and supply current typically drops
to 0.5µA. Note that the shutdown current is lowest when
V SHDN = 0.
Power Detector
The power detector generates a voltage proportional to
the output power by monitoring the output power using
an internal coupler. It is fully temperature compensated
and allows the user to set the bandwidth with an exter-
_______________________________________________________________________________________
7
2.4GHz to 2.5GHz
Linear Power Amplifier
MAX2242
Typical Application Circuit
VCC
VCC
DET
OUT
DAC
0.1µF
47kΩ
SHDN
R1
8kΩ
R2
8kΩ
VCC2
0.1µF
PD_OUT
50Ω
BIAS
33pF
VCCB
VCC
BIAS
CIRCUIT
33pF
DETECTOR
10nH
VCC1
VCC
0.1µF
100pF
RF_IN
RF_OUT
1.8pF
6pF
2.2nH
GND
GND
GND
NOTE: REFER TO MAX2242 EV KIT DATA SHEET FOR DETAILED LAYOUT INFORMATION.
Package Diagram
1.5
0.75
MAX
0.5
C4
B4
A4
C3
B3
NOT
USED
A3
C2
B2
A2
C1
B1
A1
2.0
UCSP reliability performance shows that it is capable of
performing reliably through environmental stresses.
Users should also be aware that as with any interconnect system there are electromigration-based current
limits that, in this case, apply to the maximum allowable
current in the bumps. Reliability is a function of this current, the duty cycle, lifetime, and bump temperature.
See the Absolute Maximum Ratings section for any
specific limitations listed under Continuous Operating
Lifetime.Results of environmental stress tests and additional usage data and recommendations are detailed in
the UCSP application note, which can be found on
Maxim’s website at www.maxim-ic.com.
Chip Information
0.5
TRANSISTOR COUNT: 486
BOTTOM VIEW
CHIP-SCALE PACKAGE (ALL DIMENSIONS IN mm)
8
_______________________________________________________________________________________
SIDE VIEW
2.4GHz to 2.5GHz
Linear Power Amplifier
Package Information
12L, UCSP 4x3.EPS
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information
go to www.maxim-ic.com/packages.)
PACKAGE OUTLINE, 4x3 UCSP
21-0104
F
1
1
Note: MAX2242 does not use bump B3.
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.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 _____________________ 9
© 2003 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.
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