19-0832; Rev 2; 5/10
KIT
ATION
EVALU
BLE
AVAILA
Complete, Direct-Conversion Tuner for DVB-S
and Free-to-Air Applications
General Description
The MAX2120 low-cost, direct-conversion tuner IC is
designed for satellite set-top and VSAT applications.
The IC is intended for QPSK, Digital Video Broadcast
(DVB-S), DSS, and free-to-air applications.
The MAX2120 directly converts the satellite signals
from the LNB to baseband using a broadband I/Q
downconverter. The operating frequency range extends
from 925MHz to 2175MHz.
The device includes an LNA and an RF variable-gain
amplifier, I and Q downconverting mixers, and baseband
lowpass filters with programmable cutoff frequency
control and digitally controlled baseband variable-gain
amplifiers. Together, the RF and baseband variable-gain
amplifiers provide more than 80dB of gain-control range.
The IC is compatible with virtually all QPSK demodulators.
The MAX2120 includes fully monolithic VCOs, as well as
a complete frequency synthesizer. Additionally, an on-
chip crystal oscillator is provided along with a buffered
output for driving additional tuners and demodulators.
Synthesizer programming and device configuration are
accomplished with a 2-wire serial interface. The IC fea-
tures a VCO autoselect (VAS) function that automatically
selects the proper VCO. For multituner applications, the
device can be configured to have one of two 2-wire
interface addresses. A low-power standby mode is
available whereupon the signal path is shut down while
leaving the reference oscillator, digital interface, and
buffer circuits active, providing a method to reduce
power in single and multituner applications.
The MAX2120 is the most advanced DBS tuner available
today. The low noise figure eliminates the need for an
external LNA. A small number of passive components are
needed to form a complete DVB, DBS, or VSAT RF front-
end solution. The tuner is available in a very small 28-pin
thin QFN package.
o
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Features
925MHz to 2175MHz Frequency Range
Monolithic VCO: No Calibration Required
-75dBm to 0dBm High Dynamic Range
4MHz to 40MHz Integrated Variable BW LP Filters
Single +3.3V ±5% Supply
Low-Power Standby Mode
Address Pin for Multituner Applications
Differential I/Q Interface
I
2
C 2-Wire Serial Interface
Very Small 28-Pin Thin QFN Package
MAX2120
Ordering Information
PART
MAX2120CTI+
TEMP RANGE
0°C to +70°C
PIN-PACKAGE
28 Thin QFN-EP*
*
EP = Exposed paddle.
+
Denotes a lead(Pb)-free/RoHS-compliant package.
Pin Configuration/
Functional Diagram
VCC_BB
ADDR
QDC+
QDC-
SDA
IDC-
22
21
IDC+
SCL
27
+
VCC_RF2
1
28
26
25
24
23
INTERFACE LOGIC
AND CONTROL
VCC_RF1
2
MAX2120
LPF BW
CONTROL
DC OFFSET
CORRECTION
20
IOUT-
GND
3
19
IOUT+
RFIN
4
5
DIV2/DIV4
FREQUENCY
SYNTHESIZER
÷
18
QOUT-
Applications
DirecTV and Dish Network DBS
DVB-S
Two-Way Satellite Systems
VSATs
Free-to-Air
VCC_VCO
7
8
VCOBYP
9
VTUNE
10
GNDTUNE
11
GNDSYN
12
CPOUT
13
VCC_SYN
14
XTAL
GC1
17
QOUT+
VCC_LO
6
EP
16
VCC_DIG
15
REFOUT
________________________________________________________________
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.
Complete, Direct-Conversion Tuner for DVB-S
and Free-to-Air Applications
MAX2120
ABSOLUTE MAXIMUM RATINGS
V
CC
to GND ...........................................................-0.3V to +3.9V
All Other Pins to GND.................................-0.3V to (V
CC
+ 0.3V)
RF Input Power: RFIN .....................................................+10dBm
VCOBYP, CPOUT, REFOUT, XTAL, IOUT_, QOUT_, IDC_, and
QDC_ Short-Circuit Protection.............................................10s
Continuous Power Dissipation (T
A
= +70°C)
28-Pin Thin QFN (derated 34.5mW/°C above +70°C)........2.75W
Operating Temperature Range...............................0°C to +70°C
Junction Temperature ......................................................+150°C
Storage Temperature Range .............................-65°C to +160°C
Lead Temperature (soldering, 10s) .................................+300°C
Soldering Temperature (reflow) .......................................+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
(MAX2120 Evaluation Kit: V
CC
= +3.13V to +3.47V, V
GC1
= +0.5V (max gain), T
A
= 0°C to +70°C. No input signals at RF, baseband
I/Os are open circuited, and LO frequency = 2150MHz. Default register settings except BBG[3:0] = 1011. Typical values measured
at V
CC
= +3.3V, T
A
= +25°C, unless otherwise noted.) (Note 1)
PARAMETER
SUPPLY
Supply Voltage
Supply Current
Receive mode, bit STBY = 0
Standby mode, bit STBY = 1
2.4
0.5
50
-50
Maximum gain = 0.5V
0.5
-50
0.4
2.7
+50
2.3
400
0.7 x
V
CC
0.3 x
V
CC
Digital inputs = GND or V
CC
I
SINK
= 1mA
±0.1
±1
0.4
3.13
3.3
100
3
3.47
160
V
mA
CONDITIONS
MIN
TYP
MAX
UNITS
ADDRESS SELECT INPUT (ADDR)
Digital Input-Voltage High, V
IH
Digital Input-Voltage Low, V
IL
Digital Input-Current High, I
IH
Digital Input-Current Low, I
IL
ANALOG GAIN-CONTROL INPUT (GC1)
Input Voltage Range
Input Bias Current
VCO TUNING VOLTAGE INPUT (VTUNE)
Input Voltage Range
2-WIRE SERIAL INPUTS (SCL, SDA)
Clock Frequency
Input Logic-Level High
Input Logic-Level Low
Input Leakage Current
2-WIRE SERIAL OUTPUT (SDA)
Output Logic-Level Low
V
kHz
V
V
µA
V
V
µA
V
V
µA
µA
2
_______________________________________________________________________________________
Complete, Direct-Conversion Tuner for DVB-S
and Free-to-Air Applications
AC ELECTRICAL CHARACTERISTICS
(MAX2120 Evaluation Kit: V
CC
= +3.13V to +3.47V, V
GC1
= +0.5V (max gain), T
A
= 0°C to +70°C. Default register settings except
BBG[3:0] = 1011. Typical values measured at V
CC
= +3.3V, T
A
= +25°C, unless otherwise noted.) (Note 1)
PARAMETER
MAIN SIGNAL PATH PERFORMANCE
Input Frequency Range
RF Gain-Control Range (GC1)
Baseband Gain-Control Range
In-Band Input IP3
Out-of-Band Input IP3
Input IP2
Adjacent Channel Protection
(Note 2)
0.5V < V
GC1
< 2.7V
Bits GC2 = 1111 to 0000
(Note 3)
(Note 4)
(Note 5)
(Note 6)
V
GC1
is set to 0.5V (maximum RF gain) and BBG[3:0] is
adjusted to give a 1V
P-P
baseband output level for a
-75dBm CW input tone at 1500MHz
Starting with the same BBG[3:0] setting as above, V
GC1
is adjusted to back off RF gain by 10dB (Note 7)
Minimum RF Input Return Loss
Nominal Output Voltage Swing
I/Q Amplitude Imbalance
I/Q Quadrature Phase Imbalance
Single-Ended I/Q Output
Impedance
Output 1dB Compression Voltage
Baseband Highpass -3dB
Frequency Corner
BASEBAND LOWPASS FILTERS
Filter Bandwidth Range
Rejection Ratio
Group Delay
Ratio of In-Filter-Band to Out-of-
Filter-Band Noise
FREQUENCY SYNTHESIZER
RF-Divider Frequency Range
RF-Divider Range (N)
Reference-Divider Frequency
Range
Reference-Divider Range (R)
Phase-Detector Comparison
Frequency
925
16
4
1
1
2175
2175
30
31
2
MHz
MHz
MHz
At 2 x f
-3dB
Up to 1dB bandwidth
f
INBAND
= 100Hz to 22.5MHz, f
OUTBAND
= 87.5MHz to
112.5MHz
4
39
37
25
40
MHz
dB
ns
dB
925MHz < f
RF
< 2175MHz, in 75Ω system
R
LOAD
= 2kΩ//10pF
Measured at 500kHz; filter set to 22.27MHz
Measured at 500kHz; filter set to 22.27MHz
Real Z
O
, from 1MHz to 40MHz
Differential
47nF capacitors at IDC_, QDC_
30
3
400
0.5
BASEBAND OUTPUT CHARACTERISTICS
1
±1
3.5
V
P-P
dB
Degrees
Ω
V
P-P
Hz
925
65
13
73
15
+2
+15
+40
25
8
dB
9
12
12
dB
2175
MHz
dB
dB
dBm
dBm
dBm
dB
CONDITIONS
MIN
TYP
MAX
UNITS
MAX2120
Noise Figure
_______________________________________________________________________________________
3
Complete, Direct-Conversion Tuner for DVB-S
and Free-to-Air Applications
MAX2120
AC ELECTRICAL CHARACTERISTICS (continued)
(MAX2120 Evaluation Kit: V
CC
= +3.13V to +3.47V, V
GC1
= +0.5V (max gain), T
A
= 0°C to +70°C. Default register settings except
BBG[3:0] = 1011. Typical values measured at V
CC
= +3.3V, T
A
= +25°C, unless otherwise noted.) (Note 1)
PARAMETER
Guaranteed LO Frequency
Range
LO Phase Noise
CONDITIONS
MIN
TYP
MAX
UNITS
VOLTAGE-CONTROLLED OSCILLATOR AND LO GENERATION
T
A
= 0°C to +70°C
f
OFFSET
= 10kHz
f
OFFSET
= 100kHz
f
OFFSET
= 1MHz
XTAL/REFERENCE OSCILLATOR INPUT AND OUTPUT BUFFER
XTAL Oscillator Frequency
Range
Input Overdrive Level
XTAL Output-Buffer Divider
Range
XTAL Output Voltage Swing
XTAL Output Duty Cycle
4MHz to 30MHz, C
LOAD
= 10pF
Parallel-resonance-mode crystal (Note 8)
AC-coupled sine wave input
4
0.5
1
1
1.5
50
1
8
2.0
8
2
V
P-P
%
MHz
V
P-P
925
-82
-102
-122
dBc/Hz
2175
MHz
Note 1:
Min/max values are production tested at T
A
= +70°C. Min/max limits at T
A
= 0°C and T
A
= +25°C are guaranteed by design
and characterization.
Note 2:
Gain-control range specifications met over this band.
Note 3:
In-band IIP3 test conditions: GC1 set to provide the nominal baseband output drive when mixing down a -23dBm tone at
2175MHz to 5MHz baseband (f
LO
= 2170MHz). Baseband gain is set to its default value (BBG[3:0] = 1011). Two tones at
-26dBm each are applied at 2174MHz and 2175MHz. The IM3 tone at 3MHz is measured at baseband, but is referred to the
RF input.
Note 4:
Out-of-band IIP3 test conditions: GC1 set to provide nominal baseband output drive when mixing down a -23dBm tone at
2175MHz to 5MHz baseband (f
LO
= 2170MHz). Baseband gain is set to its default value (BBG[3:0] = 1011). Two tones at
-20dBm each are applied at 2070MHz and 1975MHz. The IM3 tone at 5MHz is measured at baseband, but is referred to the
RF input.
Note 5:
Input IP2 test conditions: GC1 set to provide nominal baseband output drive when mixing down a -23dBm tone at 2175MHz
to 5MHz baseband (f
LO
= 2170MHz). Baseband gain is set to its default value (BBG[3:0] = 1011). Two tones at -20dBm
each are applied at 925MHz and 1250MHz. The IM2 tone at 5MHz is measured at baseband, but is referred to the RF input.
Note 6:
Adjacent channel protection test conditions: GC1 is set to provide the nominal baseband output drive with a 2110MHz
27.5Mbaud signal at -55dBm. GC2 set for mid-scale. The test signal will be set for PR = 7/8 and SNR of -8.5dB. An adjacent
channel at ±40MHz is added at -25dBm. DVB-S BER performance of 2E-4 will be maintained for the desired signal. GC2
may be adjusted for best performance.
Note 7:
Guaranteed by design and characterization at T
A
= +25°C.
Note 8:
See Table 14 for crystal ESR requirements.
4
_______________________________________________________________________________________
Complete, Direct-Conversion Tuner for DVB-S
and Free-to-Air Applications
Typical Operating Characteristics
(MAX2120 Evaluation Kit: V
CC
= +3.3V, baseband output frequency = 5MHz; V
GC1
= 1.2V; T
A
= +25°C. Default register settings
except BBG[3:0] = 1011.)
SUPPLY CURRENT vs. SUPPLY VOLTAGE
MAX2120 toc01
MAX2120
STANDBY MODE SUPPLY CURRENT
vs. SUPPLY VOLTAGE
MAX2120 toc02
SUPPLY CURRENT
vs. BASEBAND FILTER CUTOFF FREQUENCY
102
100
SUPPLY CURRENT (mA)
98
96
94
92
90
88
86
MAX2120 toc03
98
97
96
SUPPLY CURRENT (mA)
95
94
93
92
91
90
89
88
3.0
3.1
3.2
3.3
3.4
3.5
T
A
= 0°C
T
A
= +25°C
T
A
= +70°C
2.900
2.800
SUPPLY CURRENT (mA)
2.700
2.600
2.500
2.400
2.300
T
A
= 0°C, +25°C
104
T
A
= +70°C
3.6
3.0
3.1
3.2
3.3
3.4
3.5
3.6
84
4
8
12
16
20
24
28
32
36
40
BASEBAND FILTER CUTOFF FREQUENCY (MHz)
SUPPLY VOLTAGE (V)
SUPPLY VOLTAGE (V)
HD3 vs. OUTPUT VOLTAGE
MAX2120 toc04
QUADRATURE PHASE vs. LO FREQUENCY
MAX2120 toc05a
QUADRATURE MAGNITUDE MATCHING
vs. LO FREQUENCY
QUADRATURE MAGNITUDE MATCHING (dB)
0.8
0.6
0.4
0.2
0
-0.2
-0.4
-0.6
-0.8
-1.0
900
1200
1500
1800
2100
2400
T
A
= 0°C
T
A
= +70°C
f
BASEBAND
= 10MHz
T
A
= +25°C
MAX2120 toc05b
-10
BASEBAND 3RD-ORDER HARMONIC (dBc)
-15
-20
-25
-30
-35
-40
-45
-50
-55
-60
1.0
1.5
2.0
2.5
3.0
93.5
f
BASEBAND
= 10MHz
92.5
QUADRATURE PHASE (°)
T
A
= +25°C
91.5
90.5
89.5
88.5
87.5
86.5
T
A
= 0°C
T
A
= +70°C
1.0
3.5
900
1200
1500
1800
2100
2400
V
OUT
(V
P-P
)
LO FREQUENCY (MHz)
LO FREQUENCY (MHz)
QUADRATURE PHASE
vs. BASEBAND FREQUENCY
MAX2120 toc06a
QUADRATURE MAGNITUDE MATCHING
vs. BASEBAND FREQUENCY
QUADRATURE MAGNITUDE MATCHING (dB)
0.8
0.6
0.4
0.2
0
-0.2
-0.4
-0.6
-0.8
-1.0
0
4
8
12
16
20
BASEBAND FREQUENCY (MHz)
T
A
= +25°C
T
A
= 0°C
T
A
= +70°C
f
LO
= 925MHz
MAX2120 toc06b
93.5
f
LO
= 925MHz
92.5
QUADRATURE PHASE (°)
T
A
= +70°C
91.5
90.5
89.5
88.5
87.5
86.5
0
4
8
12
16
T
A
= +25°C
T
A
= 0°C
1.0
20
BASEBAND FREQUENCY (MHz)
_______________________________________________________________________________________
5
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