19-2494; Rev 2; 8/03
KIT
ATION
EVALU
BLE
AVAILA
5GHz Linear Power Amplifiers
General Description
Features
♦
5GHz to 6GHz Operating Frequency Range
♦
High Linear Output Power
+15dBm at 5.25GHz (MAX2840)
+18dBm at 5.25GHz (MAX2841)
♦
22dB Power Gain
♦
On-Chip Detector With 15dB Dynamic Range and
±1.0dB Detector Accuracy
♦
Simple Input and Output Matching
♦
+2.7V to +3.6V Single Supply
♦
Shutdown Mode With Less than 10µA Current
♦
2mm
✕
1.5mm Chip-Scale Package
MAX2840/MAX2841
The MAX2840/MAX2841 low-cost linear power ampli-
fiers (PAs) operate in the 5GHz to 6GHz band. The PAs
are designed for high gain and high linearity, which
makes them ideal for use in IEEE 802.11a OFDM sys-
tems. The MAX2840 delivers +15dBm output power,
and the MAX2841 delivers +18dBm output power.
The devices integrate a power detector that provides
over 15dB dynamic range and ±1.0dB accuracy. With
the detector circuit built in, an automatic level control
(ALC) function can be easily implemented.
The PAs also feature an external bias control function.
The idle current can be adjusted through an external
DAC to improve efficiency at reduced output powers
while maintaining sufficient ACPR and EVM perfor-
mance. As a result, the highest possible efficiency is
maintained at all power levels. The MAX2840/MAX2841
operate over a single +2.7V to +3.6V power-supply
range. An on-chip shutdown feature reduces operating
current to less than 10µA, eliminating the need for an
external supply switch.
The MAX2840/MAX2841 are packaged in a 2mm
✕
1.5mm chip-scale package (UCSP™), which signifi-
cantly minimizes parasitic effects and reduces the
required board area.
Ordering Information
PART
MAX2840EBC-T
MAX2841EBC-T
TEMP RANGE
-40°C to +85°C
-40°C to +85°C
PIN-
PACKAGE
3
✕
4 UCSP
3
✕
4 UCSP
TOP
MARK
AAT
AAU
Typical Operating Circuit appears at end of data sheet.
Applications
IEEE 802.11a OFDM WLAN
HiperLAN2 WLAN
5GHz Cordless Phones
SHDN
A1
BIAS
CIRCUIT
BIAS
C1
Pin Configuration
Functional Diagram
SHDN
P_DET
GND
A2
BIAS
BIAS
CIRCUIT
DETECTOR
RF_IN
B2
MAX2840
MAX2841
GND
C2
V
CC
MAX2840
MAX2841
V
CC
A3
P_DET
C3
RF_IN
RF_OUT
DET
A4
GND
GND
GND
GND
GND
B4
RF_OUT
C4
GND
UCSP is a trademark of Maxim Integrated Products, Inc.
________________________________________________________________
Maxim Integrated Products
1
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.
5GHz Linear Power Amplifiers
MAX2840/MAX2841
ABSOLUTE MAXIMUM RATINGS
V
CC
to GND ...........................................................-0.3V to +4.2V
SHDN,
BIAS, P_DET, RF_OUT to GND ......-0.3V to (V
CC
+ 0.3V)
RF_IN to GND........................................................-0.3V to +0.9V
Input Power ................................................................... +10dBm
Max VSWR Without Damage .................................................10:1
Max VSWR for Stable Operation .............................................5:1
Continuous Operating Lifetime.....................10yrs
✕
0.93
(T
A
- 60°C)
(for operating temperature 60°C < TA < 85°C)
Continuous Power Dissipation (T
A
= +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
Soldering Temperature (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.
CAUTION!
ESD SENSITIVE DEVICE
DC ELECTRICAL CHARACTERISTICS
(V
CC
= +2.7V to +3.6V, GND = 0V,
SHDN
= V
CC
, V
DAC
= 1.6V (MAX2840), V
DAC
= 1.9V (MAX2841), T
A
= -40°C to +85°C. Typical
values are measured at V
CC
= +3.3V, f
RF
= 5.25GHz, T
A
= +25°C, unless otherwise noted.) (Note 1)
PARAMETER
Supply Voltage
P
OUT
= 15dBm, V
CC
= 3.3V, MAX2840 (Notes 2, 3)
P
OUT
= 18dBm, V
CC
= 3.3V, MAX2841 (Notes 2, 3)
Supply Current
No RF signal, RF input and output
terminated with 50Ω
SHDN
= 0V, no RF signal
Digital Input Voltage High
Digital Input Voltage Low
Digital Input Current High
Digital Input Current Low
-1
2
0.8
5
MAX2840
MAX2841
CONDITIONS
MIN
2.7
155
260
120
165
0.5
10
µA
V
V
µA
µA
TYP
MAX
3.6
190
310
mA
UNITS
V
AC ELECTRICAL CHARACTERISTICS
(MAX2840/MAX2841 EV kits, V
CC
= +2.7V to +3.6V, GND = 0V,
SHDN
= V
CC
, V
DAC
= 1.6V (MAX2840), V
DAC
= 1.9V (MAX2841),
T
A
= +25°C. Typical values are measured at V
CC
= +3.3V, f
RF
= 5.25GHz, unless otherwise noted.) (Note 3)
PARAMETER
RF Frequency Range
Power Gain (Note 5)
Power Gain
(Note 4)
P
OUT
= 15dBm (MAX2840)
P
OUT
= 18dBm (MAX2841)
T
A
= +85°C, V
CC
= 3.3V (Note 5)
ACPR: -23dBc at 11MHz offset,
-31dBc at 20MHz offset,
-43dBc at 30MHz offset over 100kHz BW;
OFDM, 64-QAM signal (Notes 6, 7)
P
OUT
= 15dBm (MAX2840)
P
OUT
= 18dBm (MAX2841)
P
OUT
= 15dBm (MAX2840)
P
OUT
= 18dBm (MAX2841)
MAX2840
MAX2841
19.5
15
dBm
18
3.9
3.5
-45
%
RMS
dBc
CONDITIONS
MIN
5.15
22.8
22.5
TYP
MAX
5.35
UNITS
GHz
dB
dB
Output Power
Error Vector Magnitude (Note 7)
Harmonic Output (2f, 3f)
2
_______________________________________________________________________________________
5GHz Linear Power Amplifiers
AC ELECTRICAL CHARACTERISTICS (continued)
(MAX2840/MAX2841 EV kits, V
CC
= +2.7V to +3.6V, GND = 0V,
SHDN
= V
CC
, V
DAC
= 1.6V (MAX2840), V
DAC
= 1.9V (MAX2841),
T
A
= +25°C. Typical values are measured at V
CC
= +3.3V, f
RF
= 5.25GHz, unless otherwise noted.) (Note 3)
PARAMETER
Input VSWR
Output VSWR
Nonharmonic Spurious Output
Power Ramp Turn-On Time
Power Ramp Turn-Off Time
RF Output Detector Response
Time
SHDN
from low to high (Note 8)
SHDN
from high to low (Note 8)
External capacitor, C = 10pF
P
OUT
= 15dBm (MAX2840)
P
OUT
= 18dBm (MAX2841)
RF Output Detector Voltage
Range
Load >100kΩ (Note 7)
P
OUT
= 12dBm (MAX2840)
P
OUT
= 15dBm (MAX2841)
P
OUT
= 5dBm (MAX2840)
P
OUT
= 5dBm (MAX2841)
RF Output Detector Accuracy
RF Output Detector Slope
When output detector voltage = 1.2V
At maximum output power
1
1
0.5
1.1
1.2
1
1
0.7
0.7
±1
6
dB
dB/V
V
CONDITIONS
MIN
TYP
1.8:1
1.9:1
-60
1.5
1.5
1.5
dBc
µs
µs
µs
MAX
UNITS
MAX2840/MAX2841
Note 1:
Note 2:
Note 3:
Note 4:
Note 5:
Note 6:
Note 7:
Note 8:
Specifications over temperature range are guaranteed by design. Production tests are performed at T
A
= +85°C.
5.25GHz 64-QAM modulated OFDM signal is applied at RF input port.
Min and max values are guaranteed by design and characterization.
Operation outside of this frequency range is possible but not guaranteed.
Specifications are corrected for board losses on the EV kits (0.3dB at the input, 0.3dB at the output).
RF input signal is following IEEE 802.11a standards.
Specifications are corrected for board losses on the EV kits (0.3dB at the output).
The total turn-on/settling time required for PA output power is within 0.5dB range of the final value.
Typical Operating Characteristics
(MAX2840/MAX2841 EV kits, V
CC
= +2.7V to +3.6V, GND = 0V,
SHDN
= V
CC
, V
DAC
= 1.6V (MAX2840), V
DAC
= 1.9V (MAX2841),
T
A
= +25°C. Typical values are measured at V
CC
= +3.3V, f
RF
= 5.25GHz, unless otherwise noted.) (Note 2)
MAX2840
SUPPLY CURRENT vs. SUPPLY VOLTAGE
P
IN
= -8.9dBm
160
MAX2840/41 toc01
MAX2840
SHUTDOWN CURRENT vs. SUPPLY VOLTAGE
MAX2840/41 toc02
180
0.30
0.25
SHUTDOWN CURRENT (µA)
0.20
0.15
T
A
= +25°C
0.10
0.05
T
A
= +85°C
SUPPLY CURRENT (mA)
140
120
T
A
= -40°C
2.7
3.0
3.3
3.6
100
2.7
3.0
3.3
3.6
SUPPLY VOLTAGE (V)
0
SUPPLY VOLTAGE (V)
_______________________________________________________________________________________
3
5GHz Linear Power Amplifiers
MAX2840/MAX2841
Typical Operating Characteristics (continued)
(MAX2840/MAX2841 EV kits, V
CC
= +2.7V to +3.6V, GND = 0V,
SHDN
= V
CC
, V
DAC
= 1.6V (MAX2840), V
DAC
= 1.9V (MAX2841),
T
A
= +25°C. Typical values are measured at V
CC
= +3.3V, f
RF
= 5.25GHz, unless otherwise noted.) (Note 2)
MAX2840
SUPPLY CURRENT vs. OUTPUT POWER
MAX2840/41 toc03
MAX2840
POWER-ADDED EFFICIENCY (PAE)
vs. OUTPUT POWER
16
2.7V
14
12
PAE (%)
10
8
6
4
3.0V
MAX2840/41 toc04
MAX2840
POWER DETECTOR OUTPUT
vs. OUTPUT POWER
MAX2840/41 toc05
220
200
SUPPLY CURRENT (mA)
180
160
140
120
18
1.2
POWER DETECTOR OUTPUT (V)
1.1
1.0
0.9
0.8
0.7
0.6
2
100
0
4
8
12
16
20
OUTPUT POWER (dBm)
0
0
4
8
12
3.6V
16
20
0
4
8
12
16
OUTPUT POWER (dBm)
OUTPUT POWER (dBm)
MAX2840
INPUT AND OUTPUT RETURN LOSS
vs. FREQUENCY
MAX2840/41 toc06
MAX2840
GAIN vs. FREQUENCY
MAX2840/41 toc07
MAX2840 ACPR SPECTRUM
P
O
= +15dBm
MAX2840/41 toc08
0
INPUT AND OUTPUT RETURN LOSS (dB)
30
P
IN
= -8.9dBm
25
GAIN (dB)
-4
-8
S11
20
-12
S22
15
-16
-20
5150
10
5200
5250
FREQUENCY (MHz)
5300
5350
5150
5200
5250
FREQUENCY (MHz)
5300
5350
SPAN: 100MHz CENTER: 5.25GHz
OUTPUT POWER, 10dB/div
280
P
IN
= -4.8dBm
260
MAX2840
EVM vs. OUTPUT POWER
MAX2840/41 toc09
MAX2840
EVM vs. FREQUENCY
P
IN
= -8.9dBm
5
EVM (%)
V
CC
= 3.0V
4
V
CC
= 3.3V
MAX2840/41 toc10
MAX2841
SUPPLY CURRENT vs. SUPPLY VOLTAGE
MAX2840/41 toc011
6
P
IN
= -8.9dBm
5
EVM (%)
6
SUPPLY CURRENT (mA)
4
V
CC
= 3.0V
3
V
CC
= 3.3V
240
3
220
2
12
13
14
15
16
OUTPUT POWER (dBm)
2
5150
5200
5250
FREQUENCY (MHz)
5300
5350
200
2.7
3.0
3.3
3.6
SUPPLY VOLTAGE (V)
4
_______________________________________________________________________________________
5GHz Linear Power Amplifiers
MAX2840/MAX2841
Typical Operating Characteristics (continued)
(MAX2840/MAX2841 EV kits, V
CC
= +2.7V to +3.6V, GND = 0V,
SHDN
= V
CC
, V
DAC
= 1.6V (MAX2840), V
DAC
= 1.9V (MAX2841),
T
A
= +25°C. Typical values are measured at V
CC
= +3.3V, f
RF
= 5.25GHz, unless otherwise noted.) (Note 2)
MAX2841
SHUTDOWN CURRENT vs. SUPPLY VOLTAGE
MAX2840/41 toc12
MAX2841
SUPPLY CURRENT vs. OUTPUT POWER
MAX2840/41 toc13
MAX2841
POWER-ADDED EFFICIENCY (PAE)
vs. OUTPUT POWER
16
14
12
PAE (%)
2.7V
MAX2840/41 toc14
0.30
0.25
SHUTDOWN CURRENT (µA)
0.20
0.15
T
A
= +25°C
0.10
0.05
0
2.7
3.0
3.3
T
A
= +85°C
400
350
SUPPLY CURRENT (mA)
300
T
A
=
+25°C
250
200
150
100
T
A
=
-40°C
T
A
=
+85°C
18
10
8
6
4
2
0
3.6V
3.0V
T
A
= -40°C
3.6
0
4
8
12
16
20
24
0
5
10
15
20
25
SUPPLY VOLTAGE (V)
OUTPUT POWER (dBm)
OUTPUT POWER (dBm)
MAX2841
POWER DETECTOR OUTPUT
vs. OUTPUT POWER
MAX2840/41 toc15
MAX2841
INPUT AND OUTPUT RETURN LOSS
vs. FREQUENCY
MAX2840/41 toc16
MAX2841
GAIN vs. FREQUENCY
P
IN
= -4.8dBm
25
GAIN (dB)
MAX2840/41 toc17
2.0
POWER DETECTOR OUTPUT (V)
1.8
1.6
1.4
1.2
1.0
T
A
=
-40°C
0.8
0.6
0
5
10
15
20
T
A
=
+25°C
T
A
=
+85°C
0
INPUT AND OUTPUT RETURN LOSS (dB)
30
-4
-8
S22
20
-12
S11
-16
15
25
-20
5150
10
5200
5250
FREQUENCY (MHz)
5300
5350
5150
5200
5250
FREQUENCY (MHz)
5300
5350
OUTPUT POWER (dBm)
MAX2841 ACPR SPECTRUM
MAX2840/41 toc18
MAX2841
EVM vs. OUTPUT POWER
MAX2840/41 toc19
MAX2841
EVM vs. FREQUENCY
P
IN
= -4.8dBm
5
EVM (%)
MAX2840/41 toc20
6
P
IN
= -4.8dBm
5
EVM (%)
6
P
OUT
= +18dBm
OUTPUT POWER, 10dB/div
4
V
CC
= 3.0V
4
V
CC
= 3.0V
V
CC
= 3.3V
3
V
CC
= 3.3V
3
2
CENTER: 5.25GHz SPAN: 100MHz
13
14
15
16
17
18
19
OUTPUT POWER (dBm)
2
5150
5200
5250
FREQUENCY (MHz)
5300
5350
_______________________________________________________________________________________
5