W83194BR-KT
STEP-LESS 3-DIMM K7 CLOCK
1.0 GENERAL DESCRIPTION
The W83194BR-KT is a Clock Synthesizer which provides all clocks required for AMD K7.
W83194BR-KT provides 64 CPU/PCI frequencies which are selectable with smooth transitions by
hardware or software. W83194BR-KT also provides 13 SDRAM clocks controlled by the none-delay
buffer_in pin.
The W83194BR-KT provides step-less frequency programming by controlling the VCO freq. and the
programmable PCI clock output divisor ratio. A watchdog timer is quipped and when time out, the
RESET# pin will output 4ms pulse signal.
The W83194BR-KT accepts a 14.318 MHz reference crystal as its input. Spread spectrum built in at
±0.5% or ±0.25% to reduce EMI. Programmable stopping individual clock outputs and frequency
selection through I2C interface. The device meets the Pentium power-up stabilization, which requires
CPU and PCI clocks be stable within 2 ms after power-up. Using dual function pin for the slots (ISA,
PCI, CPU, DIMM) is not recommend.
2.0 PRODUCT FEATURES
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Supports AMD CPU with I2C.
3 CPU clocks (one free-running chipset clock controlled by I2C)
13 SDRAM clocks for 3 DIMMs
6 PCI synchronous clocks
Optional single or mixed supply:
(Vddq2 =2.5V, Vddq3 =3.3V)
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< 250ps skew among CPU and SDRAM clocks
< 250ps skew among PCI clocks
< 5ns propagation delay SDRAM from buffer input
Skew from CPU (earlier) to PCI clock 1 to 4ns, center 2.6ns.
Smooth frequency switch with selections from 66 MHz to 200 MHz CPU
Step-less frequency programming by controlling the VCO freq. and the clock output divisor ratio
I2C 2-Wire serial interface and I2C read back
±0.25% or ±0.5% spread spectrum function to reduce EMI
Programmable spread spectrum in the M/N step-less mode
Programmable registers to enable/stop each output and select modes
MODE pin for power Management and RESET# out when Watch Dog Timer time out
One 48 MHz for USB & one 24 MHz for super I/O
48-pin SSOP package
Publication Release Date: June 2000
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Revision 0.43