DATASHEET

TRIPLE PLL FIELD PROG. SPREAD SPECTRUM CLOCK SYNTHESIZER

ICS280

IDT® TRIPLE PLL FIELD PROG. SPREAD SPECTRUM CLOCK SYNTHESIZER

1

ICS280

REV G 030212

Description

The ICS280 field programmable spread spectrum clock

synthesizer generates up to four high-quality,

high-frequency clock outputs including multiple reference

clocks from a low-frequency crystal input. It is designed to

replace crystals, crystal oscillators and stand alone spread

spectrum devices in most electronic systems.

outputs, the ICS280 contains a One-Time Programmable

(OTP) ROM for field programmability. Programming

features include input/output frequencies, spread spectrum

amount and eight selectable configuration registers.

Using Phase-Locked Loop (PLL) techniques, the device

runs from a standard fundamental mode, inexpensive

crystal, or clock. It can replace multiple crystals and

oscillators, saving board space and cost.

The ICS280 is also available in factory programmed custom

versions for high-volume applications.

Features

Block Diagram

Crystal

Oscillator

GND

3

3

VDD

PDTS

PLL2

PLL3

Divide

Logic

and

Output

Enable

Control

S2:S0

3

OTP

ROM

with PLL

Values

X2

Crystal or

Clock Input

External capacitors

are required with a crystal input.

X1/ICLK

PLL1 with

Spread

Spectrum

CLK1

CLK3

CLK4

CLK2