W83194AR-W

e

200MHZ CLOCK FOR WHITNEY CHIPSET

Publication Release Date: Nov. 1999

- 1 -

Revision 0.50

1.0 GENERAL DESCRIPTION

The W83194AR-We is a Clock Synthesizer for Intel Whitney chipset. W83194AR-We provides all

clocks required for high-speed RISC or CISC microprocessor and also provides 64 different

frequencies of CPU, SDRAM, PCI, 3V66, IOAPIC clocks frequency setting. All clocks are externally

selectable with smooth transitions.

The W83194AR-We provides I

each clock outputs and provides 0.5% and 0.75% center type spread spectrum to reduce EMI.

The W83194AR-We accepts a 14.318 MHz reference crystal as its input and runs on a 3.3V supply.

High drive PCI and SDRAM CLOCK outputs typically provide greater than 1 V /ns slew rate into 30

pF loads. CPU CLOCK outputs typically provide better than 1 V /ns slew rate into 20 pF loads as

maintaining 50± 5% duty cycle. The fixed frequency outputs as REF, 24MHz, and 48 MHz provide

better than 0.5V /ns slew rate.

2.0 PRODUCT FEATURES

• 2 CPU clocks

• 9 SDRAM clocks for 2 DIMMs

• 8 PCI synchronous clocks.

• Optional single or mixed supply:

(VddR = VddP=VddS = Vdd48 = Vdd3 = 3.3V, VddA=VddC=2.5V)

•

Skew form CPU to PCI clock -1 to 4 ns, center 2.6 ns

•

Smooth frequency switch with selections from 66.8 to 200MHz

• 0.5% and 0.75% center type spread spectrum

• Programmable registers to enable/stop each output and select modes

(mode as Tri-state or Normal )

• Two 48 MHz pins for USB

• 24 MHz for super I/O

• 48-pin SSOP package