MAX2172

Direct-Conversion to Low-IF Tuner for Digital Audio

Broadcast

High-Performance Digital Radio Tuner Incorporates Fast and Accurate RSSI Function

OVERVIEW

Description

The MAX2172 direct-conversion to low-IF tuner is designed for digital

audio broadcast (DAB) and terrestrial digital multimedia broadcast (T-

DMB) applications, covering an input frequency range of 168MHz to

240MHz (VHF-III), 1452MHz to 1492MHz (L-band), and also 87MHz

to 108MHz (FM). The MAX2172 achieves a high level of component

integration, allowing lowpower, tuner-on-board designs. The direct-

conversion to low-IF architecture eliminates the need for an IF-SAW

filter while providing a balanced 2.048MHz center frequency

baseband output to the demodulator.

The MAX2172 provides a buffered reference clock at the crystal

frequency.

A sigma-delta fractional-N synthesizer is incorporated to optimize

both close-in and wideband phase noise performances for OFDM

applications where sensitivity to both 1kHz phase noise and

wideband phase noise related to strong adjacents can be a problem.

The MAX2172 is available in a 40-pin thin QFN package (6mm x

6mm) with an exposed pad. Electrical performance is guaranteed

over the extended -40°C to +85°C temperature range.

MAX2172: Functional Diagram

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