19-0806; Rev 1; 11/08
KIT
ATION
EVALU
BLE
AVAILA
2.3GHz to 2.7GHz Wireless
Broadband RF Transceiver
Features
♦
2.3GHz to 2.7GHz Wideband Operation
♦
Complete RF Transceiver, PA Driver, and
Crystal Oscillator
0dBm Linear OFDM Transmit Power
-70dBr Tx Spectral Emission Mask
2.3dB Rx Noise Figure
Tx/Rx I/Q Error and LO Leakage Detection
Monolithic Low-Noise VCO with -39dBc
Integrated Phase Noise
Programmable Tx I/Q Lowpass
Anti-Aliasing Filter
Sigma-Delta Fractional-N PLL with
20Hz Step Size
45dB Tx Gain-Control Range
94dB Receive Gain-Control Range
60dB Analog RSSI Instantaneous
Dynamic Range
4-Wire SPI™ Digital Interface
I/Q Analog Baseband Interface
Digitally Tuned Crystal Oscillator
On-Chip Digital Temperature Sensor Read-Out
♦
+2.7V to +3.6V Transceiver Supply
♦
Low-Power Shutdown Current
♦
Small 48-Pin Thin QFN Package
(6mm x 6mm x 0.8mm)
General Description
The MAX2837 direct-conversion zero-IF RF transceiver
is designed specifically for 2.3GHz to 2.7GHz wireless
broadband systems. The MAX2837 completely inte-
grates all circuitry required to implement the RF trans-
ceiver function, providing RF-to-baseband receive path;
and baseband-to-RF transmit path, VCO, frequency
synthesizer, crystal oscillator, and baseband/control
interface. The device includes a fast-settling sigma-
delta RF synthesizer with smaller than 20Hz frequency
steps and a crystal oscillator, which allows the use of a
low-cost crystal in place of a TCXO. The transceiver IC
also integrates circuits for on-chip DC offset cancella-
tion, I/Q error, and carrier-leakage detection circuits.
Only an RF bandpass filter (BPF), crystal, RF switch,
PA, and a small number of passive components are
needed to form a complete wireless broadband RF
radio solution.
The MAX2837 completely eliminates the need for an
external SAW filter by implementing on-chip monolithic
filters for both the receiver and transmitter. The baseband
filters along with the Rx and Tx signal paths are optimized
to meet stringent noise figure and linearity specifications.
The device supports up to 2048 FFT OFDM and imple-
ments programmable channel filters for 1.75MHz to
28MHz RF channel bandwidths. The transceiver requires
only 2µs Tx-Rx switching time, which includes frequency
transient settling. The IC is available in a small, 48-pin thin
QFN package measuring only 6mm x 6mm x 0.8mm.
MAX2837
Applications
802.16-2004 Fixed WiMAX
Korea Wibro and 802.16e Mobile WiMAX
Dual Mode
TM
WiMAX/802.11b/g Wi-Fi
Proprietary Wireless Broadband Systems
4G/LTE Systems
Ordering Information
PART
MAX2837ETM+TD
TEMP RANGE
-40°C to +85°C
PIN-
PACKAGE
48 TQFN-EP*
Dual Mode is a trademark of Maxim Integrated Products, Inc.
SPI is a trademark of Motorola, Inc.
*EP
= Exposed paddle.
+Denotes
a lead-free package.
Pin Configuration appears at end of data sheet.
________________________________________________________________
Maxim Integrated Products
1
For information on other Maxim products, visit Maxim’s website at www.maxim-ic.com.
2.3GHz to 2.7GHz Wireless
Broadband RF Transceiver
MAX2837
ABSOLUTE MAXIMUM RATINGS
V
CCLNA
, V
CCTXMX
, V
CCTXPAD
, V
CCDIG
, V
CCCP
, V
CCXTAL
,
V
CCVCO
, V
CCRXVGA
, V
CCRXFL
and V
CCRXMX
to
GND...................................................................-0.3V to +3.9V
B1–B7, TXRF_,
CS,
SCLK, DIN, DOUT, TXBBI_, TXBBQ_, RXHP,
RXBBI_, RXBBQ_, RSSI, ENABLE, BYPASS, CPOUT_,
CLOCKOUT, XTAL1, XTAL2, RXRF_,RXENABLE, TXENABLE
to GND.......................................-0.3V to (Operating V
CC
+ 0.3V)
RXBBI_, RXBBQ_, RSSI, BYPASS, CPOUT_, DOUT, CLOCKOUT,
PABIAS Short-Circuit Duration............................................10s
RF Input Power ...............................................................+10dBm
Continuous Power Dissipation (T
A
= +70°C)
48-Pin Thin QFN (derates 37mW/°C above +70°C).......2.96W
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
CAUTION!
ESD SENSITIVE DEVICE
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
(MAX2837 evaluation kit: V
CC_
= 2.7V to 3.6V, Rx set to the maximum gain;
CS
= high, RXHP = SCLK = DIN = low, RSSI and clock output
buffer are off, no signal at RF inputs, all RF inputs and outputs terminated into 50Ω, receiver baseband outputs are open; 90mV
RMS
dif-
ferential I and Q signals applied to I, Q baseband inputs of transmitter in transmit mode, f
REF
= 40MHz, registers set to recommended
settings and corresponding test mode, T
A
= -40°C to +85°C, unless otherwise noted. Typical values are at V
CC
= 2.8V, f
LO
= 2.5GHz,
and T
A
= +25°C, unless otherwise noted.) (Note 1)
PARAMETER
Supply Voltage
V
CC_
Shutdown mode, T
A
= +25
°
C
Standby mode
Supply Current
Rx mode
Tx mode, T
A
= +25
°
C
Rx calibration mode
Tx calibration mode
D9:D8 = 00 in A4:A0 = 00100
Rx I/Q Output Common-Mode
Voltage
D9:D8 = 01 in A4:A0 = 00100
D9:D8 = 10 in A4:A0 = 00100
D9:D8 = 11 in A4:A0 = 00100
Tx Baseband Input Common-
Mode Voltage Operating Range
Tx Baseband Input Bias Current
DC-coupled
Source current
V
CC
-
0.4
0.4
-1
-1
+1
+1
0.5
10
0.85
CONDITIONS
MIN
2.7
10
35
91
145
135
110
1.0
1.1
1.2
1.35
1.2
20
V
µA
45
110
170
160
135
1.20
V
mA
TYP
MAX
3.6
UNITS
V
µA
LOGIC INPUTS: ENABLE, TXENABLE, RXENABLE, SCLK, DIN,
CS
, B7:B1, RXHP
Digital Input-Voltage High, V
IH
Digital Input-Voltage Low, V
IL
Digital Input-Current High, I
IH
Digital Input-Current Low, I
IL
V
V
µA
µA
2
_______________________________________________________________________________________
2.3GHz to 2.7GHz Wireless
Broadband RF Transceiver
DC ELECTRICAL CHARACTERISTICS (continued)
(MAX2837 evaluation kit: V
CC_
= 2.7V to 3.6V, Rx set to the maximum gain;
CS
= high, RXHP = SCLK = DIN = low, RSSI and clock output
buffer are off, no signal at RF inputs, all RF inputs and outputs terminated into 50Ω, receiver baseband outputs are open; 90mV
RMS
dif-
ferential I and Q signals applied to I, Q baseband inputs of transmitter in transmit mode, f
REF
= 40MHz, registers set to recommended
settings and corresponding test mode, T
A
= -40°C to +85°C, unless otherwise noted. Typical values are at V
CC
= 2.8V, f
LO
= 2.5GHz,
and T
A
= +25°C, unless otherwise noted.) (Note 1)
PARAMETER
LOGIC OUTPUTS: DOUT
Digital Output-Voltage High, V
OH
Digital Output-Voltage Low, V
OL
Sourcing 100µA
Sinking 100µA
V
CC
-
0.4
0.4
V
V
CONDITIONS
MIN
TYP
MAX
UNITS
MAX2837
AC ELECTRICAL CHARACTERISTICS—Rx MODE
(MAX2837 evaluation kit: V
CC
_ = 2.8V, f
RF
= 2.502GHz, f
LO
= 2.5GHz; receiver baseband I/Q outputs at 90mV
RMS
(-21dBV), f
REF
= 40MHz, ENABLE = RXENABLE =
CS
= high, TXENABLE = SCLK = DIN = low, with power matching for the differential RF
pins using the typical applications and registers set to default settings and corresponding test mode, T
A
= +25°C, unless otherwise noted.
Lowpass filter is set to 10MHz RF channel BW. Unmodulated single-tone RF input signal is used, unless otherwise indicated.) (Note 1)
PARAMETER
RF Input Frequency Range
Peak-to-Peak Gain Variation over
RF Input Frequency Range
RF Input Return Loss
Total Voltage Gain
Tested at band edges and band center
All LNA gain settings
T
A
= -40°C to +85°C
Maximum gain, B7:B1 = 0000000
Minimum gain, B7:B1 = 1111111
90
CONDITIONS
MIN
2.3
0.8
13
99
5
8
16
32
0.2
µs
2
dB
13
TYP
MAX
2.7
UNITS
GHz
dB
dB
dB
RECEIVER SECTION: LNA RF INPUT TO BASEBAND I/Q OUTPUTS
From max RF gain to max RF gain - 8dB
RF Gain Steps
From max RF gain to max RF gain - 16dB
From max RF gain to max RF gain - 32dB
Any RF or baseband gain change; gain settling to within
±1dB
of steady state; RXHP = 1
Any RF or baseband gain change; gain settling to within
±0.1dB
of steady state; RXHP = 1
Baseband Gain Range
Baseband Gain Minimum
Step Size
Voltage gain
≥
65dB with max RF gain (B7:B6 = 00)
Voltage gain = 50dB with max RF gain - 8dB
(B7:B6 = 01)
DSB Noise Figure
Voltage gain = 45dB with max RF gain - 16dB
(B7:B6 = 10)
Voltage gain = 15dB with max RF gain - 32dB
(B7:B6 = 11)
From maximum baseband gain (B5:B1 = 00000) to
minimum baseband gain (B5:B1 = 11111),
T
A
= -40°C to +85°C
58
Gain Change Settling Time
62
66
dB
2
2.3
5.5
17
27
dB
dB
_______________________________________________________________________________________
3
2.3GHz to 2.7GHz Wireless
Broadband RF Transceiver
MAX2837
AC ELECTRICAL CHARACTERISTICS—Rx MODE (continued)
MAX2837 evaluation kit: V
CC
_ = 2.8V, f
RF
= 2.502GHz, f
LO
= 2.5GHz; receiver baseband I/Q outputs at 90mV
RMS
(-21dBV), f
REF
= 40MHz, ENABLE = RXENABLE =
CS
= high, TXENABLE = SCLK = DIN = low, with power matching for the differential RF
pins using the typical applications and registers set to default settings and corresponding test mode, T
A
= +25°C, unless otherwise noted.
Lowpass filter is set to 10MHz RF channel BW. Unmodulated single-tone RF input signal is used, unless otherwise indicated.) (Note 1)
PARAMETER
CONDITIONS
Max RF gain (B7:B6 = 00)
In-Band Input P-1dB
Max RF gain - 8dB (B7:B6 = 01)
Max RF gain - 16dB (B7:B6 = 10)
Max RF gain - 32dB (B7:B6 = 11)
Maximum Output Signal Level
Over passband frequency range; at any gain setting;
1dB compression point
Max RF gain (B7:B6 = 00), AGC set for -65dBm
wanted signal
Max RF gain - 8dB (B7:B6 = 01), AGC set for -55dBm
wanted signal
Out-of-Band Input IP3 (Note 2)
Max RF gain - 16dB (B7:B6 = 10), AGC set for -40dBm
wanted signal
Max RF gain - 32dB (B7:B6 = 11), AGC set for -30dBm
wanted signal
I/Q Phase Error
I/Q Gain Imbalance
Rx I/Q Output Load Impedance
(R || C)
I/Q Output DC Droop
50kHz baseband output; 1 variation
50kHz baseband output; 1 variation
Minimum differential resistance
Maximum differential capacitance
After switching RXHP to 0; average over 1μs after any
gain change, or 2μs after receive enabled with 100Hz
interval AC-coupling, 1 variation
No RF input signal; measure at 3μs after receive
enable; RXHP = 1 for 0 to 2μs and set to 0 after 2μs,
1 variation
Transmitter I/Q input to receiver I/Q output; transmitter
B6:B1 = 000011, receiver B5:B1 = 10100 programmed
through SPI
-6
+16
0.15
0.1
10
5
±1
Degrees
dB
k
pF
mV/ms
MIN
TYP
-37
-29
-21
-4
2.5
-11
-8
dBm
V
P-P
dBm
MAX
UNITS
I/Q Static DC Offset
±1
mV
Loopback Gain
(for Receiver I/Q Calibration)
RECEIVER BASEBAND FILTERS
-4.5
0
+4.5
dB
At 15MHz
Baseband Filter Rejection
At 20MHz
At > 40MHz
RXHP = 1 (used before AGC completion)
D5:D4 = 00
Baseband Highpass Filter
Corner Frequency
RXHP = 0 (used after
AGC completion)
address A4:A0 = 01110
D5:D4 = 01
D5:D4 = 10
D5:D4 = 11
57
75
90
650
0.1
1
30
100
kHz
dB
4
_______________________________________________________________________________________
2.3GHz to 2.7GHz Wireless
Broadband RF Transceiver
AC ELECTRICAL CHARACTERISTICS—Rx MODE (continued)
MAX2837 evaluation kit: V
CC
_ = 2.8V, f
RF
= 2.502GHz, f
LO
= 2.5GHz; receiver baseband I/Q outputs at 90mV
RMS
(-21dBV), f
REF
= 40MHz, ENABLE = RXENABLE =
CS
= high, TXENABLE = SCLK = DIN = low, with power matching for the differential RF
pins using the typical applications and registers set to default settings and corresponding test mode, T
A
= +25°C, unless otherwise noted.
Lowpass filter is set to 10MHz RF channel BW. Unmodulated single-tone RF input signal is used, unless otherwise indicated.) (Note 1)
PARAMETER
CONDITIONS
A4:A0 = 00010 serial bits D7:D4 = 0000
A4:A0 = 00010 serial bits D7:D4 = 0001
A4:A0 = 00010 serial bits D7:D4 = 0010
A4:A0 = 00010 serial bits D7:D4 = 0011
A4:A0 = 00010 serial bits D7:D4 = 0100
A4:A0 = 00010 serial bits D7:D4 = 0101
A4:A0 = 00010 serial bits D7:D4 = 0110
RF Channel BW Supported by
Baseband Filter
A4:A0 = 00010 serial bits D7:D4 = 0111
A4:A0 = 00010 serial bits D7:D4 = 1000
A4:A0 = 00010 serial bits D7:D4 = 1001
A4:A0 = 00010 serial bits D7:D4 = 1010
A4:A0 = 00010 serial bits D7:D4 = 1011
A4:A0 = 00010 serial bits D7:D4 = 1100
A4:A0 = 00010 serial bits D7:D4 = 1101
A4:A0 = 00010 serial bits D7:D4 = 1110
A4:A0 = 00010 serial bits D7:D4 = 1111
Baseband Gain Ripple
Baseband Group Delay Ripple
Baseband Filter Rejection for
5MHz RF Channel BW
Baseband Filter Rejection for
10MHz RF Channel BW
RSSI
RSSI Minimum Output Voltage
RSSI Maximum Output Voltage
RSSI Slope
RSSI Output Settling Time
To within 3dB of steady
state
+32dB signal step
-32dB signal step
R
LOAD
≥
10kΩ
R
LOAD
≥
10kΩ
0.4
2.2
30
200
800
V
V
mV/dB
ns
0 to 2.3MHz for BW = 5MHz
0 to 4.6MHz for BW = 10MHz
0 to 2.3MHz for BW = 5MHz
0 to 4.6MHz for BW = 10MHz
At 3.3MHz
At > 21MHz
At 6.7MHz
At > 41.6MHz
MIN
TYP
1.75
2.25
3.5
5.0
5.5
6.0
7.0
8.0
9.0
10.0
12.0
14.0
15.0
20.0
24.0
28.0
1.3
1.3
90
50
7
85
7
85
dB
P-P
ns
P-P
dB
dB
MHz
MAX
UNITS
MAX2837
_______________________________________________________________________________________
5