19-5009; Rev 1; 3/10
5GHz, 4-Channel MIMO Transmitter
General Description
The MAX2850 is a single-chip, 4-channel RF transmitter
IC designed for 5GHz wireless HDMI applications. The
IC includes all circuitry required to implement the com-
plete 4-channel MIMO RF transmitter function and crys-
tal oscillator, providing a fully integrated transmit path,
VCO, frequency synthesis, and baseband/control inter-
face. It includes a fast-settling, sigma-delta RF fractional
synthesizer with 76Hz frequency programming step
size. The IC also integrates on-chip I/Q amplitude and
phase-error calibration circuits. Dynamic on/off control
of four external PAs is implemented with programmable
precision voltages. A 4-to-1 analog mux routes external
PA power-detect voltages to the RSSI pin.
On-chip monolithic filters are included for transmitter I/Q
baseband signal reconstruction to support both 20MHz
and 40MHz RF channels. The baseband filtering and
Tx signal paths are optimized to meet stringent WHDI
requirements. The upconverter local oscillator is coher-
ent among all the transmitter channels.
The reverse-link control channel uses an on-chip 5GHz
OFDM receiver. It shares the RF synthesizer and LO gen-
eration circuit with the MIMO transmitters. The receiver
includes both an in-channel RSSI and an RF RSSI.
The MIMO transmitter chip is housed in a small, 68-pin
thin QFN leadless plastic package with exposed pad.
S
Features
5GHz 4x MIMO Downlink Transmitters, Single
Uplink IEEE 802.11a Receiver
4900MHz to 5900MHz Frequency Range
-5dBm Transmit Power (54Mbps OFDM)
Coherent LO Among Transmitters
31dB Tx Gain-Control Range with 0.5dB Step
Size, Digitally Controlled
Tx/Rx I/Q Error and LO Leakage Detection and
Adjustment
Programmable 20MHz/40MHz Tx I/Q Lowpass
Anti-Aliasing Filter
4-to-1 Analog Mux for PA Power Detect
4-Channel PA On/Off Control
4.5dB Rx Noise Figure
70dB Rx Gain-Control Range with 2dB Step
Size, Digitally Controlled
60dB Dynamic Range Receiver RSSI
RF Wideband Receiver RSSI
Programmable 20MHz/40MHz Rx I/Q Lowpass
Channel Filters
Sigma-Delta Fractional-N PLL with 76Hz
Resolution
Monolithic Low-Noise VCO with -35dBc
Integrated Phase Noise
4-Wire SPI™ Digital Interface
I/Q Analog Baseband Interface
Digital Tx/Rx Mode Control
On-Chip Digital Temperature Sensor Readout
Complete Baseband Interface
Digital Tx/Rx Mode Control
MAX2850
Applications
5GHz Wireless HDMI (WHDI)
5GHz FDD Backhaul and WiMax™
5GHz MIMO Transmitter Up to Four Spatial
Streams
5GHz Beam Steering Transmitter
S
+2.7V to +3.6V Supply Voltage
S
Small, 68-Pin Thin QFN Package (10mm x 10mm)
Ordering Information
PART
MAX2850ITK+
TEMP RANGE
-25NC to +85NC
PIN-PACKAGE
68 Thin QFN-EP*
*EP
= Exposed pad.
+Denotes
a lead(Pb)-free/RoHS-compliant package.
WiMax is a trademark of WiMax Forum.
SPI is a trademark of Motorola, Inc.
Typical Operating Circuit appears at end of data sheet.
_______________________________________________________________
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.
5GHz, 4-Channel MIMO Transmitter
MAX2850
ABSOLUTE MAXIMUM RATINGS
V
CC_
Pins to GND ................................................-0.3V to +3.9V
RF Inputs Maximum Current: RXRF+, RXRF-
to GND ................................................................-1mA to +1mA
RF Outputs: TXRF1+, TXRF1-, TXRF2+, TXRF2-,
TXRF3+, TXRF3-, TXRF4+, TXRF4- to GND .....-0.3V to +3.9V
Analog Inputs: TXBB1I+, TXBB1I-, TXBB1Q+,
TXBB1Q-, TXBB2I+, TXBB2I-, TXBB2Q+,
TXBB2Q-, TXBB3I+, TXBB3I-, TXBB3Q+, TXBB3Q-,
TXBB4I+, TXBB4I-, TXBB4Q+, TXBB4Q-, PA_DET1,
PA_DET2, PA_DET3, PA_DET4, XTAL,
XTAL_CAP to GND ...........................................-0.3V to +3.9V
Analog Outputs: RXBBI+, RXBBI-, RXBBQ+,
RXBBQ-, RSSI, CLKOUT2, VCOBYP, CPOUT+,
CPOUT-, PA_BIAS1, PA_BIAS2,
PA_BIAS3, PA_BIAS4 to GND ..........................-0.3V to +3.9V
Digital Inputs: ENABLE,
CS,
SCLK, DIN to GND ... -0.3V to +3.9V
Digital Outputs: DOUT, CLKOUT to GND ............-0.3V to +3.9V
Short-Circuit Duration
Analog Outputs ................................................................. 10s
Digital Outputs................................................................... 10s
RF Input Power .............................................................. +10dBm
RF Output Differential Load VSWR ........................................ 6:1
Continuous Power Dissipation (T
A
= +85NC)
68-Pin Thin QFN (derate 29.4mW/NC above +70NC) ....2352mW
Operating Temperature Range .......................... -25NC to +85NC
Junction Temperature .....................................................+150NC
Storage Temperature Range............................ -65NC to +160NC
Lead Temperature (soldering, 10s) ................................+300NC
Soldering Temperature (reflow) ......................................+260NC
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
(Operating conditions, unless otherwise specified: V
CC
= 2.7V~3.6V, ENABLE set according to operating mode,
CS
= high, SCLK
= DIN = low, transmitter in maximum gain, T
A
= -25NC to +85NC. Power matching and termination for the differential RF output pins
using the
Typical Operating Circuit.
100mV
RMS
differential I and Q signals applied to I/Q baseband inputs of transmitters in transmit
mode. Typical values measured at V
CC
= 2.85V, T
A
= +25NC, LO frequency = 5.35GHz, T
A
= +25NC. Channel bandwidth is set to
40MHz. PA control pins open circuit, V
CC_PA_BIAS
is disconnected.) (Note 1)
PARAMETERS
Supply Voltage, V
CC
Shutdown mode
T
A
= +25NC
XTAL oscillator, load =
10pF
TCXO input, load =
10kI||10pF
One transmitter is on
Four transmitters are on
One transmitter is on
Four transmitters are on
CONDITIONS
MIN
2.7
10
3
7.4
60
188
505
135
214
532
268
0.9
0.5
Source current
10
1.1
11
89
235
661
174
261
686
327
1.3
1.1
20
V
V
FA
mA
TYP
MAX
3.6
UNITS
V
FA
DC ELECTRICAL CHARACTERISTICS
Clock-out only mode
Supply Current
Standby mode
Transmit mode
Receive mode
Transmit calibration mode
Receive calibration mode
Rx I/Q Output Common-Mode
Voltage
Tx Baseband Input Common-
Mode Voltage Operating Range
Tx Baseband Input Bias Current
2
______________________________________________________________________________________
5GHz, 4-Channel MIMO Transmitter
(Operating conditions, unless otherwise specified: V
CC
= 2.7V~3.6V, ENABLE set according to operating mode,
CS
= high, SCLK
= DIN = low, transmitter in maximum gain, T
A
= -25NC to +85NC. Power matching and termination for the differential RF output pins
using the
Typical Operating Circuit.
100mV
RMS
differential I and Q signals applied to I/Q baseband inputs of transmitters in transmit
mode. Typical values measured at V
CC
= 2.85V, T
A
= +25NC, LO frequency = 5.35GHz, T
A
= +25NC. Channel bandwidth is set to
40MHz. PA control pins open circuit, V
CC_PA_BIAS
is disconnected.) (Note 1)
PARAMETERS
LOGIC INPUTS: ENABLE, SCLK, DIN,
CS
Digital Input-Voltage High, V
IH
Digital Input-Voltage Low, V
IL
Digital Input-Current High, I
IH
Digital Input-Current Low, I
IL
LOGIC OUTPUTS: DOUT, CLKOUT
Digital Output-Voltage High, V
OH
Digital Output-Voltage Low, V
OL
Digital Output Voltage in
Shutdown Mode
Sourcing 1mA
Sinking 1mA
Sinking 1mA
V
OL
V
CC
-
0.4
0.4
V
V
V
-1
-1
V
CC
-
0.4
0.3
+1
+1
V
V
FA
FA
CONDITIONS
MIN
TYP
MAX
UNITS
DC ELECTRICAL CHARACTERISTICS (continued)
MAX2850
(Operating conditions, unless otherwise specified: V
CC
= 2.7V~3.6V, RF frequency = 5.351GHz, T
A
= -25NC to +85NC. LO frequency
= 5.35GHz. Reference frequency = 40MHz, ENABLE = high,
CS
= high, SCLK = DIN = low, with power matching at RXRF+ and
RXRF- differential ports using the
Typical Operating Circuit.
Receiver I/Q output at 100mV
RMS
loaded with 10kI differential load
resistance and 10pF load capacitance. The RSSI pin is loaded with 10kI load resistance to ground. Typical values measured at V
CC
= 2.85V, channel bandwidths of 40MHz, T
A
= +25NC.) (Note 1)
PARAMETER
RF Input Frequency Range
Peak-to-Peak Gain Variation
over RF Frequency Range at
One Temperature
RF Input Return Loss
Total Voltage Gain
4.9GHz to 5.35GHz
5.35GHz to 5.9GHz
All LNA settings
Maximum gain; Main address 1 D7:0 = 11111111
Minimum gain; Main address 1 D7:0 = 00000000
Main address 1 D7:D5 = 110
RF Gain Steps Relative to
Maximum Gain
Main address 1 D7:D5 = 101
Main address 1 D7:D5 = 001
Main address 1 D7:D5 = 000
Baseband Gain Range
Baseband Gain Step
RF Gain Change Settling Time
Gain settling to within
Q0.5dB
of steady state; RXHP = 1
From maximum baseband gain (Main address 1 D3:D0
= 1111) to minimum baseband gain (Main address 1
D3:D0 = 0000)
27.5
61
CONDITIONS
MIN
4.9
0.3
2.2
-6
68
-2
-8
-16
-32
-40
30
2
400
32.5
dB
dB
ns
dB
+5
TYP
MAX
5.9
2.6
5.3
UNITS
GHz
dB
dB
dB
RECEIVER SECTION: RF INPUT TO I/Q BASEBAND LOADED OUTPUT (Includes 50I to 100I RF Balun and Matching)
AC ELECTRICAL CHARACTERISTICS—Rx MODE
_______________________________________________________________________________________
3
5GHz, 4-Channel MIMO Transmitter
MAX2850
(Operating conditions, unless otherwise specified: V
CC
= 2.7V~3.6V, RF frequency = 5.351GHz, T
A
= -25NC to +85NC. LO frequency
= 5.35GHz. Reference frequency = 40MHz, ENABLE = high,
CS
= high, SCLK = DIN = low, with power matching at RXRF+ and
RXRF- differential ports using the
Typical Operating Circuit.
Receiver I/Q output at 100mV
RMS
loaded with 10kI differential load
resistance and 10pF load capacitance. The RSSI pin is loaded with 10kI load resistance to ground. Typical values measured at V
CC
= 2.85V, channel bandwidths of 40MHz, T
A
= +25NC.) (Note 1)
PARAMETER
Baseband Gain-Change Settling
Time
CONDITIONS
Gain settling to within
Q0.5dB
of steady state; RXHP = 1
Balun input referred,
integrated from 10kHz
to 9.5MHz at I/Q base-
band output for 20MHz
RF bandwidth
Balun input referred,
integrated from 10kHz
to 19MHz at I/Q base-
band output for 40MHz
RF bandwidth
Maximum RF gain (Main
address 1 D7:D5 = 111)
Maximum RF gain - 16dB
(Main address 1 D7:D5 = 101)
Maximum RF gain (Main
address 1 D7:D5 = 111)
Maximum RF gain - 16dB
(Main address 1 D7:D5 = 101)
-65dBm wanted signal; RF
gain = max (Main address 1
D7:D0 = 11101001)
-49dBm wanted signal; RF
gain = max - 16dB (Main
address 1 D7:D0 = 10101001)
-45dBm wanted signal; RF
gain = max - 32dB (Main
address 1 D7:D0 = 00111111)
-65dBm wanted signal; RF
gain = max (Main address 1
D7:D0 = 11101001)
-49dBm wanted signal; RF
gain = max - 16dB (Main
address 1 D7:D0 = 10101001)
-45dBm wanted signal; RF
gain = max - 32dB (Main
address 1 D7:D0 = 00101001)
MIN
TYP
200
4.5
15
4.5
15
MAX
UNITS
ns
AC ELECTRICAL CHARACTERISTICS—Rx MODE (continued)
DSB Noise Figure
dB
-13
20MHz RF channel;
two tone jammers at
+25MHz and +48MHz
frequency offset with
-39dBm/tone
-5
11
dBm
-13
Out-of-Band Input IP3
40MHz RF channel;
two tone jammers at
+50MHz and +96MHz
frequency offset with
-39dBm/tone
-5
11
1dB Gain Desensitization by
Alternate Channel Blocker
Blocker at
Q40MHz
offset frequency for 20MHz RF
channel
Blocker at
Q80MHz
offset frequency for 40MHz RF
channel
Max RF gain (Main address 1 D7:D5 = 111)
Max RF gain - 8dB (Main address 1 D7:D5 = 110)
Max RF gain - 16dB (Main address 1 D7:D5 = 101)
Max RF gain - 32dB (Main address 1 D7:D5 = 001)
Over passband frequency range; at any gain setting;
1dB compression point
-24
dBm
-24
-32
-24
-16
0
0.63
V
P-P
dBm
Input 1dB Gain Compression
Output 1dB Gain Compression
4
______________________________________________________________________________________
5GHz, 4-Channel MIMO Transmitter
(Operating conditions, unless otherwise specified: V
CC
= 2.7V~3.6V, RF frequency = 5.351GHz, T
A
= -25NC to +85NC. LO frequency
= 5.35GHz. Reference frequency = 40MHz, ENABLE = high,
CS
= high, SCLK = DIN = low, with power matching at RXRF+ and
RXRF- differential ports using the
Typical Operating Circuit.
Receiver I/Q output at 100mV
RMS
loaded with 10kI differential load
resistance and 10pF load capacitance. The RSSI pin is loaded with 10kI load resistance to ground. Typical values measured at V
CC
= 2.85V, channel bandwidths of 40MHz, T
A
= +25NC.) (Note 1)
PARAMETER
Baseband -3dB Lowpass Corner
Frequency
Baseband Filter Stopband
Rejection
CONDITIONS
Main address 0 D1 = 0
Main address 0 D1 = 1
Rejection at 30MHz offset frequency for 20MHz channel
Rejection at 60MHz offset frequency for 40MHz channel
57
57
MIN
TYP
9.5
19
70
70
600
10
MAX
UNITS
MHz
dB
kHz
AC ELECTRICAL CHARACTERISTICS—Rx MODE (continued)
MAX2850
Baseband -3dB Highpass Corner Main address 5 D1 = 1
Frequency
Main address 5 D1 = 0
Steady-State I/Q Output DC Error
with AC-Coupling
50Fs after enabling receive mode and toggling RxHP
from 1 to 0, averaged over many measurements if I/Q
noise voltage exceeds 1mV
RMS
, at any given gain set-
ting, no input signal, 1-sigma value
1MHz baseband output, 1-sigma value
1MHz baseband output, 1-sigma value
1MHz baseband output (Note 2)
LO frequency
Receiver Spurious Signal
Emissions
RF RSSI Output Voltage
Baseband RSSI Slope
Baseband RSSI Maximum Output
Voltage
Baseband RSSI Minimum Output
Voltage
RF Loopback Conversion Gain
Tx VGA gain at maximum (Main address 9 D9:D4
= 111111); Rx VGA gain at maximum - 24dB (Main
address 1 D3:D0 = 0101)
-6
2 x LO frequency
3 x LO frequency
4 x LO frequency
-20dBm input power
19.5
2
mV
I/Q Gain Imbalance
I/Q Phase Imbalance
Sideband Suppression
0.1
0.2
40
-75
-62
-75
-60
1.75
26.5
2.3
0.5
35.5
dB
degrees
dB
dBm/
MHz
V
mV/dB
V
V
+2
+10
dB
(Operating conditions, unless otherwise specified: V
CC
= 2.7V~3.6V, RF frequency = 5.351GHz, T
A
= -25NC to +85NC. LO frequency
= 5.35GHz. Reference frequency = 40MHz, ENABLE = high,
CS
= high, SCLK = DIN = low, with power matching at TXRF+ and
TXRF- differential ports using the
Typical Operating Circuit.
100mV
RMS
sine and cosine signal applied to I/Q baseband inputs of
transmitter (differential DC-coupled). Typical values measured at V
CC
= 2.85V, channel bandwidths of 40MHz, T
A
= +25NC.) (Note 1)
PARAMETER
RF Output Frequency Range
Peak-to-Peak Gain Variation over
RF Band
At one temperature
CONDITIONS
MIN
4.9
3
TYP
MAX
5.9
6.4
UNITS
GHz
dB
TRANSMIT SECTION: Tx BASEBAND I/Q INPUTS TO RF OUTPUTS (Includes Matching and Balun Loss)
AC ELECTRICAL CHARACTERISTICS—Tx MODE
_______________________________________________________________________________________
5