MAX2121 Datasheet, PDF (1/18 Pages) Maxim Integrated Products – Complete Direct-Conversion L-Band Tuner 925MHz to 2175MHz Frequency Range

19-5959; Rev 0; 6/11
EVAALVUAAILTAIOBNLEKIT
Complete Direct-Conversion L-Band Tuner
General Description
The MAX2121 low-cost, direct-conversion tuner IC is
designed for satellite set-top and VSAT applications.
The device directly converts the satellite signals from
the LNB to baseband using a broadband I/Q downcon-
verter. 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 base-
band lowpass filters and digitally controlled baseband
variable-gain amplifiers. Together, the RF and base-
band variable-gain amplifiers provide more than 80dB
of gain control range.
The device 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 inter-
face. 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 inter-
face, and buffer circuits active, providing a method to
reduce power in single and multituner applications.
The device is the most advanced broadband/VSAT
DBS tuner available. The low noise figure eliminates the
need for an external LNA. A small number of passive
components are needed to form a complete broadband
satellite tuner DVB-S2 RF front-end solution. The tuner
is available in a very small, 5mm x 5mm, 28-pin thin
QFN package.
VSATs
Applications
Features
♦ 925MHz to 2175MHz Frequency Range
♦ Monolithic VCO
Low Phase Noise: -97dBc/Hz at 10kHz
No Calibration Required
♦ High Dynamic Range: -75dBm to 0dBm
♦ Integrated LP Filters: 123.75MHz
♦ Single +3.3V ±5% Supply
♦ Low-Power Standby Mode
♦ Address Pin for Multituner Applications
♦ Differential I/Q Interface
♦ I²C 2-Wire Serial Interface
♦ Very Small, 5mm x 5mm, 28-Pin TQFN Package
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
MAX2121ETI+
-40°C to +85°C
28 TQFN-EP*
*EP = Exposed pad.
+Denotes a lead(Pb)-free/RoHS-compliant package.
Functional Diagram
+ ²⁸
27
26
V_{CC_RF2} 1
V_{CC_RF1} 2
INTERFACE LOGIC
AND CONTROL
25
24
MAX2121
23
22
DC OFFSET
CORRECTION
21 IDC+
20 IOUT-
GND 3
19 ^IOUT+
RFIN 4
18 QOUT-
GC1 5
V_{CC_LO} 6
DIV2/DIV4
EP
FREQUENCY
SYNTHESIZER
17 ^QOUT+
16 V_{CC_DIG}
V_{CC_VCO} 7
8
15 REFOUT
9
10
11
12
13
14
________________________________________________________________ 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.