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.
title | Download file |
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MAX2121B Data Sheet | MAX2121B.pdf |
Part Number | Ref. Clock Freq. (MHz) | Noise Figure (dB) | VSUPPLY (V) | ISUPPLY (mA) | Applications | Footprint (mm x mm) | Oper. Temp. (°C) | Package/Pins | Budgetary Price |
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typ | See Notes | ||||||||
MAX2121B | 12 to 30 | 8 | 3.13 to 3.47 | 148 | DBS Navigation Set-Top Boxes VSAT | 5.0 x 5.0 | -40 to +85 | TQFN/28 | $4.25 @1k |
Part Number | Status | Recommended Replacement | Package | Temp | RoHS |
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MAX2121BETI+ | Active | TQFN,;28 pin;26 mm² | -40°C to +85°C | Lead Free | |
MAX2121BETI+T | Active | TQFN,;28 pin;26 mm² | -40°C to +85°C | Lead Free |