MAXIM MAX2120 Technical data

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 on­chip 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 fea­tures 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 front­end solution. The tuner is available in a very small 28-pin
thin QFN package.

Applications

DirecTV and Dish Network DBS

DVB-S

Two-Way Satellite Systems

VSATs

Free-to-Air

Features

o 925MHz to 2175MHz Frequency Range
o Monolithic VCO: No Calibration Required
o -75dBm to 0dBm High Dynamic Range
o 4MHz to 40MHz Integrated Variable BW LP Filters
o Single +3.3V ±5% Supply
o Low-Power Standby Mode
o Address Pin for Multituner Applications
o Differential I/Q Interface
o I2C 2-Wire Serial Interface
o Very Small 28-Pin Thin QFN Package

MAX2120

Complete, Direct-Conversion Tuner for DVB-S

and Free-to-Air Applications

________________________________________________________________

Maxim Integrated Products

1

19-0832; Rev 2; 5/10

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.

EVALUATION KIT

AVAILABLE

VTUNE

GNDSYN

CPOUT

VCC_SYN

XTAL

VCOBYP

SCL

VCC_BB

QDC-

ADDR

QDC+

IDC-

RFIN

GC1

VCC_LO

+

÷

IOUT+

QOUT-

VCC_DIG

GNDTUNE

SDA

19

17

16

3

5

18

4

6

VCC_VCO

REFOUT

15

7

GND

IOUT-

20

2

VCC_RF1

21

IDC+

1

26 24 23

10 12

25

11 132214

27

9

28

8

VCC_RF2

MAX2120

INTERFACE LOGIC

AND CONTROL

DC OFFSET

CORRECTION

LPF BW

CONTROL

DIV2/DIV4

EP

FREQUENCY

SYNTHESIZER

QOUT+

Pin Configuration/

Functional Diagram

Ordering Information

*

EP = Exposed paddle.

+

Denotes a lead(Pb)-free/RoHS-compliant package.

PART TEMP RANGE PIN-PACKAGE

MAX2120CTI+ 0°C to +70°C 28 Thin QFN-EP*

MAX2120

Complete, Direct-Conversion Tuner for DVB-S
and Free-to-Air Applications

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

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.

VCCto 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

DC ELECTRICAL CHARACTERISTICS

(MAX2120 Evaluation Kit: VCC= +3.13V to +3.47V, V

GC1

= +0.5V (max gain), TA= 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, TA = +25°C, unless otherwise noted.) (Note 1)

CAUTION! ESD SENSITIVE DEVICE

PARAMETER CONDITIONS MIN TYP MAX UNITS

SUPPLY

Supply Voltage 3.13 3.3 3.47 V

Supply Current

ADDRESS SELECT INPUT (ADDR)

Digital Input-Voltage High, VIH 2.4 V

Digital Input-Voltage Low, VIL 0.5 V

Digital Input-Current High, IIH 50 µA

Digital Input-Current Low, IIL -50 µA

ANALOG GAIN-CONTROL INPUT (GC1)

Input Voltage Range Max imum gain = 0.5V 0.5 2.7 V

Input Bias Current -50 +50 µA

VCO TUNING VOLTAGE INPUT (VTUNE)

Input Voltage Range 0.4 2.3 V

2-WIRE SERIAL INPUTS (SCL, SDA)

Cloc k Frequenc y 400 kH z

Input Logic-Level High

Input Logic-Level Low

Input Leakage Current Digital inputs = GND or VCC ±0.1 ±1 µA

2-WIRE SERIAL OUTPUT (SDA)

Output Logic-Level Low I

Receive mode, bit STBY = 0 100 160

Standby mode, bit STBY = 1 3

= 1mA 0.4 V

SINK

0.7 x
V

CC

V

0.3 x
V

CC

mA

V

MAX2120

Complete, Direct-Conversion Tuner for DVB-S

and Free-to-Air Applications

_______________________________________________________________________________________ 3

AC ELECTRICAL CHARACTERISTICS

(MAX2120 Evaluation Kit: VCC= +3.13V to +3.47V, V

GC1

= +0.5V (max gain), TA= 0°C to +70°C. Default register settings except

BBG[3:0] = 1011. Typical values measured at V

CC

= +3.3V, TA = +25°C, unless otherwise noted.) (Note 1)

PARAMETER CONDITIONS MIN TYP MAX UNITS

MAIN SIGNAL PATH PERFORMANCE

Input Frequency Range (Note 2) 925 2175 MHz

RF Gain-Control Range (GC1) 0.5V < V

Baseband Gain-Control Range Bits GC2 = 1111 to 0000 13 15 dB

In-Band Input IP3 (Note 3) +2 dBm

Out-of-Band Input IP3 (Note 4) +15 dBm

Input IP2 (Note 5) +40 dBm

Adjacent Channel Protection (Note 6) 25 dB

V

is set to 0.5V (maximum RF gain) and BBG[3:0] is

GC1

adjusted to give a 1V

Noise Figure

Minimum RF Input Return Loss 925MHz < f

BASEBAND OUTPUT CHARACTERISTICS

Nominal Output Voltage Swing R

I/Q Amplitude Imbalance Measured at 500kHz; filter set to 22.27MHz ±1 dB

I/Q Quadrature Phase Imbalance Measured at 500kHz; filter set to 22.27MHz 3.5 Degrees

Single-Ended I/Q Output
Impedance

Output 1dB Compression Voltage Differential 3 V

Baseband Highpass -3dB
Frequency Corner

BASEBAND LOWPASS FILTERS

Filter Bandwidth Range 4 40 MHz

Rejection Ratio At 2 x f

Group Delay Up to 1dB bandwidth 37 ns

Ratio of In-Filter-Band to Out-of­Filter-Band Noise

FREQUENCY SYNTHESIZER

RF-Divider Frequency Range 925 2175 MHz

RF-Divider Range (N) 16 2175

Reference-Divider Frequency
Range

Reference-Divider Range (R) 1 31

Phase-Detector Comparison
Frequency

-75dBm CW input tone at 1500MHz

Starting with the same BBG[3:0] setting as above, V
is adjusted to back off RF gain by 10dB (Note 7)

LOAD

Real Z

O

47nF capacitors at IDC_, QDC_ 400 Hz

f

INBAND

112.5MHz

< 2.7V 65 73 dB

GC1

< 2175MHz, in 75Ω system 12 dB

RF

= 2kΩ//10pF 0.5 1 V

, from 1MHz to 40MHz 30 Ω

-3dB

= 100Hz to 22.5MHz, f

baseband output level for a

P-P

OUTBAND

= 87.5MHz to

GC1

4 30 MHz

1 2 MHz

8

912

39 dB

25 dB

dB

P-P

P-P

MAX2120

Complete, Direct-Conversion Tuner for DVB-S
and Free-to-Air Applications

4 _______________________________________________________________________________________

AC ELECTRICAL CHARACTERISTICS (continued)

(MAX2120 Evaluation Kit: VCC= +3.13V to +3.47V, V

GC1

= +0.5V (max gain), TA= 0°C to +70°C. Default register settings except

BBG[3:0] = 1011. Typical values measured at V

CC

= +3.3V, TA = +25°C, unless otherwise noted.) (Note 1)

Note 1: Min/max values are production tested at TA= +70°C. Min/max limits at TA= 0°C and TA= +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.

PARAMETER CONDITIONS MIN TYP MAX UNITS

VOLTAGE-CONTROLLED OSCILLATOR AND LO GENERATION

Guaranteed LO Frequency
Range

LO Phase Noise

XTAL/REFERENCE OSCILLATOR INPUT AND OUTPUT BUFFER

XTAL Oscillator Frequency
Range

Input Overdrive Level AC-coupled sine wave input 0.5 1 2.0 V

XTAL Output-Buffer Divider
Range

XTAL Output Voltage Swing 4MHz to 30MHz, C

XTAL Output Duty Cycle 50 %

T

= 0°C to +70°C 925 2175 MHz

A

f

OFFSET

f

OFFSET

f

OFFSET

Parallel-resonance-mode crystal (Note 8) 4 8 MHz

= 10kHz -82

= 100kHz -102

= 1MHz -122

18

= 10pF 1 1.5 2 V

LOAD

dBc/Hz

P-P

P-P

MAX2120

Complete, Direct-Conversion Tuner for DVB-S

and Free-to-Air Applications

_______________________________________________________________________________________

5

Typical Operating Characteristics

(MAX2120 Evaluation Kit: VCC= +3.3V, baseband output frequency = 5MHz; V

GC1

= 1.2V; TA= +25°C. Default register settings

except BBG[3:0] = 1011.)

SUPPLY CURRENT vs. SUPPLY VOLTAGE

98

97

96

95

94

93

92

91

SUPPLY CURRENT (mA)

90

89

88

3.0 3.6

TA = +70°C

TA = +25°C

TA = 0°C

SUPPLY VOLTAGE (V)

HD3 vs. OUTPUT VOLTAGE

-10

-15

-20

-25

-30

-35

-40

-45

-50

BASEBAND 3RD-ORDER HARMONIC (dBc)

-55

-60

1.0 3.5
V

(V

)

OUT

P-P

QUADRATURE PHASE

vs. BASEBAND FREQUENCY

93.5

fLO = 925MHz

92.5

91.5

90.5

89.5

QUADRATURE PHASE (°)

88.5

87.5

86.5

020

BASEBAND FREQUENCY (MHz)

3.53.43.33.23.1

3.02.52.01.5

TA = +70°C

TA = +25°C

MAX2120 toc01

MAX2120 toc04

TA = 0°C

161284

STANDBY MODE SUPPLY CURRENT

vs. SUPPLY VOLTAGE

2.900

2.800

2.700

2.600

2.500

SUPPLY CURRENT (mA)

2.400

2.300

TA = +70°C

TA = 0°C, +25°C

3.0 3.6
SUPPLY VOLTAGE (V)

QUADRATURE PHASE vs. LO FREQUENCY

93.5

f

= 10MHz

BASEBAND

92.5

91.5

90.5

89.5

QUADRATURE PHASE (°)

88.5

87.5

86.5

TA = +25°C

TA = +70°C

TA = 0°C

900 2400

LO FREQUENCY (MHz)

MAX2120 toc06a

3.53.43.33.23.1

2100180015001200

QUADRATURE MAGNITUDE MATCHING (dB)

vs. BASEBAND FILTER CUTOFF FREQUENCY

104

102

MAX2120 toc02

100

98

96

94

92

90

SUPPLY CURRENT (mA)

88

86

84

440

BASEBAND FILTER CUTOFF FREQUENCY (MHz)

QUADRATURE MAGNITUDE MATCHING

1.0

f

BASEBAND

0.8

MAX2120 toc05a

0.6

0.4

0.2

0

-0.2

-0.4

-0.6

-0.8

QUADRATURE MAGNITUDE MATCHING (dB)

-1.0
900 2400

QUADRATURE MAGNITUDE MATCHING

vs. BASEBAND FREQUENCY

1.0

fLO = 925MHz

0.8

0.6

0.4

0.2

0

-0.2

-0.4

-0.6

-0.8

-1.0

TA = +25°C

020

BASEBAND FREQUENCY (MHz)

SUPPLY CURRENT

vs. LO FREQUENCY

= 10MHz

TA = +25°C

TA = 0°C

LO FREQUENCY (MHz)

TA = +70°C

TA = 0°C

MAX2120 toc03

3628 32242016128

MAX2120 toc05b

TA = +70°C

2100180015001200

MAX2120 toc06b

161284

MAX2120

Complete, Direct-Conversion Tuner for DVB-S
and Free-to-Air Applications

6 _______________________________________________________________________________________

Typical Operating Characteristics (continued)

(MAX2120 Evaluation Kit: VCC= +3.3V, baseband output frequency = 5MHz; V

GC1

= 1.2V; TA= +25°C. Default register settings

except BBG[3:0] = 1011.)

BASEBAND FILTER

FREQUENCY RESPONSE

MAX2120 toc07

BASEBAND FREQUENCY (MHz)

BASEBAND OUTPUT LEVEL (dB)

604020

-60

-50

-30

-40

-20

-10

0

-80

-70

080

BASEBAND FILTER HIGHPASS

FREQUENCY RESPONSE

MAX2120 toc08

BASEBAND FREQUENCY (MHz)

BASEBAND OUTPUT LEVEL (dB)

1000

-10

-8

-4

-6

-2

0

2

-14

-12

100 10,000

PROGRAMMED f

-3dB

FREQUENCY

vs. MEASURED f

-3dB

FREQUENCY

MAX2120 toc09

PROGRAMMED f

-3dB

FREQUENCY (MHz)

MEASURED f

-3dB

FREQUENCY (MHz)

402015 25 30 35510

5

10

20

15

25

35

30

40

45

0

045

LPF[7:0] = 12 + (f

-3dB

- 4MHz) / 290kHz

BASEBAND FILTER 3dB FREQUENCY

vs. TEMPERATURE

MAX2120 toc10

TEMPERATURE (°C)

BASEBAND GAIN ERROR AT f

-3dB

(dB)

4020 30 605010

-0.8

-0.6

0

-0.4

-0.2

0.2

0.6

0.4

0.8

1.0

-1.0
070

NORMALIZED TO TA = +25°C

INPUT POWER vs. V

GC1

MAX2120 toc11

V

GC1

(V)

INPUT POWER (dBm)

2.52.01.51.0

-60

-50

-40

-30

-20

-10

0

10

-80

-70

0.5 3.0

TA = +70°C

TA = +25°C

ADJUST BBG[3:0] FOR 1V

P-P

BASEBAND OUTPUT WITH
P

IN

= -75dBm AND V

GC1

= 0.5V

NOISE FIGURE vs. FREQUENCY

MAX2120 toc12

FREQUENCY (MHz)

NOISE FIGURE (dB)

210019001700150013001100

8.0

8.5

9.0

9.5

10.0

7.5
900 2300

TA = +70°C

TA = +25°C

ADJUST BBG[3:0] FOR 1V

P-P

BASEBAND OUTPUT WITH
P

IN

= -75dBm AND V

GC1

= 0.5V

MAX2120

Complete, Direct-Conversion Tuner for DVB-S

and Free-to-Air Applications

_______________________________________________________________________________________

7

Typical Operating Characteristics (continued)

(MAX2120 Evaluation Kit: VCC= +3.3V, baseband output frequency = 5MHz; V

GC1

= 1.2V; TA= +25°C. Default register settings

except BBG[3:0] = 1011.)

NOISE FIGURE vs. INPUT POWER

MAX2120 toc13

INPUT POWER (dBm)

NOISE FIGURE (dB)

-20-30-40-50-60-70

20

10

30

40

50

60

70

0

-80 0-10

ADJUST BBG[3:0] FOR 1V

P-P

BASEBAND OUTPUT WITH
P

IN

= -75dBm AND V

GC1

= 0.5V

f

LO

= 1500MHz

OUT-OF-BAND IIP3 vs. INPUT POWER

MAX2120 toc14

INPUT POWER (dBm)

OUT-OF-BAND IIP3 (dBm)

-20-30-40-50-60-70

-10

-20

0

10

20

30

-30

-80 0-10

SEE NOTE 4 ON PAGE 4 FOR CONDITIONS

IN-BAND IIP3 vs. INPUT POWER

MAX2120 toc15

INPUT POWER (dBm)

IN-BAND IIP3 (dBm)

-20-30-40-50-60-70

-30

-50

-40

-10

-20

0

10

20

30

-60

-80 0-10

SEE NOTE 3 ON PAGE 4 FOR CONDITIONS

IIP2 vs. INPUT POWER

MAX2120 toc16

INPUT POWER (dBm)

IIP2 (dBm)

-20-30-40-50-60-70

0

10

30

20

40

50

60

-10

-80 0-10

SEE NOTE 5 ON PAGE 4 FOR CONDITIONS

INPUT RETURN LOSS vs. FREQUENCY

MAX2120 toc17

FREQUENCY (MHz)

INPUT RETURN LOSS (dB)

202518001350 15751125

-20

-15

-10

-5

0

-25
900 2250

V

GC1

= 2.7V

V

GC1

= 0.5V

PHASE NOISE AT 10kHz OFFSET

vs. CHANNEL FREQUENCY

MAX2120 toc18

CHANNEL FREQUENCY (MHz)

PHASE NOISE AT 10kHz OFFSET (dBc/Hz)

206518751305 1495 16851115

-86

-82

-78

-74

-70

-90

-84

-80

-76

-72

-88

925 2255