Integrated

Circuit

Systems, Inc.

General Description

Features

ICS9120-46

Modem and Audio Clock Generator

9120-46 Rev B 052497P

Block Diagram

The ICS9120-46 is a high performance frequency generator

designed to support the clock requirements of communication

and audio interfaces. It offers the clock frequencies required

by 28.8 baud modem plus sound system. These frequencies

are synthesized from 14.7456 MHz reference oscillator whose

buffered output is available for the reference.

High accuracy, low-jitter PLLs meet the -96dB signal-to-

noise ratios required by 16-bit audio systems. Fast output

clock edge rates minimize board induced jitter.

The on-chip XTAL oscillator accuracy is better than ±100ppm

for an AT cut, 18pF load crystal with initial accuracy of ppm

plus TC, aging and load variation of ±20ppm each assuming

33pF ±5% external load capacitors.

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Generates 49.92 MHz, 40.32 MHz and 14.7456 MHz

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Single 14.7456 MHz crystal reference

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49.92 MHz accuracy tracks 40.32 MHz reference

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80ps one sigma jitter maintains 16-bit performance

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Output rise/fall times less than 1.5ns

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On-chip loop filter components

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3.0-5.5V supply range

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8-pin, 150-mil SOIC package

Applications

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Specifically designed to support the high performance

requirements of communication and audio interfaces.

ICS reserves the right to make changes in the device data identified in this

publication without further notice. ICS advises its customers to obtain the latest

version of all device data to verify that any information being relied upon by the

customer is current and accurate.