Integrated

Circuit

Systems, Inc.

General Description

Features

ICS9147-16

Block Diagram

Pentium is a trademark of Intel Corporation

9147-16 Rev A 072897P

Pin Configuration

The ICS9147-16 generates all clocks required for high

speed RISC or CISC microprocessor systems such as Intel

PentiumPro. Two different reference frequency multiplying

factors are externally selectable with smooth frequency

transitions. Glitch-free Stop clock control is provided for

CPU and BUS clocks. Complete chip low current mode is

achieved with the Power Down# pin.

High drive BUS outputs typically provide greater than 1 V/

ns slew rate into 30pF loads. CPU outputs typically provide

better than 1V/ns slew rate into 20 pF loads while

outputs typically provide better than 0.5V/ns slew rates.

Separate buffer supply pins VDDL allow for nominal 3.3V

voltage or reduced voltage swing (from 2.9 to 2.5V) for

CPU (1:4) and IOAPIC outputs.

•

Generates four processor, eight bus, four 14.31818

MHz, two 48 MHz clocks for USB support.

•

CPU to BUS clock skew 1 to 4ns (CPU early)

•

Synchronous clocks skew matched to 250ps window on

CPU and 500ps window on BUS.

•

Selectable multiplying ratios

•

Glitch free stop clock controls CPUEN and BUSEN

•

3.0V – 3.7V supply range, 2.5V to VDD supply range for

CPU (1:4) clocks and IOAPIC clock.

•

48-pin SSOP package

48-Pin SSOP

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.