MAX2121B:L-Band Tuner with Programmable Baseband Filter

Simplify Design with Programmable 40MHz to 124MHz IF Filter

The MAX2121B 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 downconverter. The operating frequency range extends from 925MHz to 2250MHz. The device includes an LNA and an RF variable-gain amplifier, I and Q downconverting mixers, and digitally controlled baseband filters (40MHz to 124MHz) and variable-gain amplifiers. Together, the RF and baseband 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 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 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 TQFN package.

Key Features
  • Monolithic Receiver Saves Cost and Space
    • Integrated VCO with Low Phase Noise: -97dBc/Hz at 10kHz
    • Integrated 14-Bit Fractional-N Synthesizer
    • Address Pin Allows for Multi-Tuner Applications
  • Low Power Reduces Cost
    • 495mW Power Dissipation
    • 10mW Standby Mode
  • High Dynamic Range Eliminates Need for External LNA and/or Attenuators
    • -75dBm to 0dBm Input Power
    • 8dB Noise Figure
  • Integrated LP Filters Simplify Design
    • Programmable Bandwidth from 40MHz to 124MHz
  • Differential I/Q Interface Minimizes EMI
    • 1VP-P Full-Scale Outputs
  • Serial Interface and Small Package Reduce Size
    • 5mm x 5mm, 28-Pin TQFN Package
    • I²C 2-Wire Serial Interface
MAX2121B: Functional Diagram
MAX2121B: Functional Diagram
Applications/Uses
  • DBS Tuner
  • Navigation Systems
  • Satellite Set-Top Box
  • VSATs
DataSheet
titleDownload file
MAX2121B Data SheetMAX2121B.pdf
Parametrics
Part NumberRef. Clock Freq.
(MHz)
Noise Figure
(dB)
VSUPPLY
(V)
ISUPPLY
(mA)
ApplicationsFootprint
(mm x mm)
Oper. Temp.
(°C)
Package/PinsBudgetary
Price
typSee Notes
MAX2121B12 to 3083.13 to 3.47148DBS
Navigation
Set-Top Boxes
VSAT
5.0 x 5.0-40 to +85TQFN/28$4.25 @1k
Design kits & evaluation modules
Related Products
  • MAX2112:Complete, Direct-Conversion Tuner for DVB-S2 Applications
  • MAX2769:Universal GPS Receiver
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX2121BETI+ActiveTQFN,;28 pin;26 mm²-40°C to +85°CLead Free
MAX2121BETI+TActiveTQFN,;28 pin;26 mm²-40°C to +85°CLead Free