DATASHEET

TRIPLE PLL FIELD PROGRAMMABLE SS VERSACLOCK SYNTHESIZER

ICS345

IDT™ / ICS™ TRIPLE PLL FIELD PROGRAMMABLE SS VERSACLOCK SYNTHESIZER 1

ICS345

REV K 110207

Description

The ICS345 field programmable clock synthesizer

generates up to nine high-quality, high-frequency clock

outputs including multiple reference clocks from a

low-frequency crystal or clock input. It is designed to

replace crystals and crystal oscillators in most electronic

systems.

outputs, the ICS345 contains a One-Time Programmable

(OTP) ROM to allow field programmability. Programming

features include eight selectable configuration registers, up

to two sets of four low-skew outputs, and optional Spread

Spectrum outputs.

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 ICS345 is also available in factory programmed custom

versions for high-volume applications.

Features

clocks, see the ICS342. For three output clocks, see the

ICS343. For more than three outputs, see the ICS345 or

ICS348.

Block Diagram

C rystal

O scillator

PLL1 with

Spread

Spec trum

GN D

2

3

VDD

PD TS

PLL2

PLL3

Divide

Logic

and

Output

Enable

Control

S2:S 0

CLK1

CLK9

CLK8

CLK7

CLK6

CLK5

CLK4

CLK3

CLK2

3

OT P

RO M

with

PLL

Values

X2

C rystal or

cloc k input

E xternal capacitors are

required w ith a crystal input.

X1/ICLK