EVALUATION KIT AVAILABLE
MAX2112
Complete, Direct-Conversion
Tuner for DVB-S2 Applications
General Description
Features
The MAX2112 low-cost, direct-conversion tuner IC is
designed for satellite set-top and VSAT applications.
The IC is intended for 8PSK and Digital Video
Broadcast (DVB-S2) applications.
The MAX2112 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 DVB-S2 demodulators.
The MAX2112 includes fully monolithic VCOs, as well as
a complete fractional-N 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 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.
Functional Diagrams
The MAX2112 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-S2 RF frontend solution. The tuner is available in a very small
28-pin thin QFN package.
o 925MHz to 2175MHz Frequency Range
o Monolithic VCO
Low Phase Noise: -97dBc/Hz at 10kHz
No Calibration Required
o High Dynamic Range: -75dBm to 0dBm
o Integrated Variable BW LP Filters: 4MHz to 40MHz
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 TQFN Package
Ordering Information
TEMP RANGE
PIN-PACKAGE
MAX2112CTI+
PART
0°C to +70°C
28 Thin QFN-EP*
MAX2112ETI+
-40°C to +85°C
28 Thin QFN-EP*
*EP = Exposed paddle.
+Denotes a lead(Pb)-free/RoHS-compliant package.
ADDR
VCC_RF2
SDA
VCC_BB
QDC-
QDC+
IDC-
+
SCL
Pin Configuration/
Functional Diagram
28
27
26
25
24
23
22
1
21
LPF BW
CONTROL
IDC+
20
DC OFFSET
CORRECTION
MAX2112
INTERFACE LOGIC
AND CONTROL
IOUT-
DirecTV and Dish Network DBS
2
GND
3
19
IOUT+
RFIN
4
18
QOUT-
GC1
Applications
VCC_RF1
5
17
QOUT+
16
VCC_DIG
15
REFOUT
DVB-S2
FREQUENCY
SYNTHESIZER
DIV2/DIV4
7
8
9
10
11
12
13
GNDTUNE
GNDSYN
CPOUT
VCC_SYN
EP
VTUNE
VCC_VCO
Pin Configurations appear at end of data sheet.
Functional Diagrams continued at end of data sheet.
UCSP is a trademark of Maxim Integrated Products, Inc.
6
VCOBYP
VCC_LO
For pricing, delivery, and ordering information, please contact Maxim Direct
at 1-888-629-4642, or visit Maxim’s website at www.maximintegrated.com.
14
XTAL
VSATs
19-0869; Rev 2; 5/10