Integrated

Circuit

Systems, Inc.

General Description

Features

ICS9159-07

9159-07 Rev C 060697

Block Diagram

The ICS9159-07 is a low-cost frequency generator designed

specifically for NexGen Nx586 systems. The integrated

buffer minimizes skew and provides the CPU clocks required

by the NexGen Nx586 microprocessor. A 14.318 MHz

XTAL oscil-lator provides the reference clock to generate

standard Nx586 frequencies. The CPU clock makes gradual

frequency transi-tions without violating the PLL timing of

internal microproc-essor clock multipliers.

Either synchronous (2XCPU/3) or asynchronous (32 MHz)

PCI bus operation can be selected. Green PC systems are

supported through doze mode.

•

Three CPU clocks operate up to 65 MHz at 3.3V, plus

smooth transitions

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Selection of nine frequencies, tristate

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Seven BUS clocks support sync or async bus

operation

•

Integrated buffer outputs drive up to 10pF loads

•

3.13 to 5.25V (3.3±5%, 5.0±5%) supply range

•

28-pin SOIC package

•

Clock duty cycles 45/55

NexGen is a trademark of NexGen Corporation.

Applications

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Ideal for NexGen Nx586 PCI-based motherboard designs

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.