W83194R Winbond Electronics Corp America, W83194R Datasheet - Page 2

• Manufacturer Part Number: W83194R
• Description: Description = 166MHz SiS540/630 Clock Gen., 3-DIMM, With S.S.T. ;; Package = Ssop 48
• Manufacturer: Winbond Electronics Corp America

1. GENERAL DESCRIPTION
The W83194R-630A is a Clock Synthesizer for SiS 540/630 chipset. W83194R-630A provides all
clocks required for high-speed RISC or CISC microprocessor such as AMD,Cyrix,Intel Pentium,
Pentium II and also provides 16 different frequencies of CPU clocks frequency setting. All clocks are
externally selectable with smooth transitions. The W83194R-630A makes SDRAM in synchronous or
asynchronous frequency with CPU clocks.
The W83194R-630A provides I
each clock outputs and W83194R-630A provides the 0.5%, 0.75% center type and 0~0.5% down type
spread spectrum to reduce EMI.
The W83194R-630A 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. PRODUCT FEATURES
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• 14 SDRAM clocks for 3 DIMMs
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(mode as Tri-state or Normal )
Supports Pentium, Pentium II, AMD and Cyrix CPUs with I
3 CPU clocks
7 PCI synchronous clocks.
Optional single or mixed supply:
(All Vdd = 3.3V) or (Other s Vdd = 3.3V, VddLCPU=2.5V)
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Programmable registers to enable/stop each output and select modes
48 MHz for USB
24 MHz for super I/O
Packaged in 48-pin SSOP
Skew form CPU to PCI clock 1 to 4 ns, center 2.6 ns
SDRAM frequency synchronous or asynchronous to CPU clocks
Smooth frequency switch with selections from 66 to 166mhz
0.5%, 0.75%center type, 0~0.5% down type spread spectrum to reduce EMI
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C 2-Wire serial interface and I
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C serial bus interface to program the registers to enable or disable
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C read back
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C.
Publication Release Date:May. 2000
W83194R-630A
Revision 1.0