W83194R-630

166MHz CLOCK FOR SIS CHIPSET

GENERAL DESCRIPTION

The A 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 I2C serial bus interface to program the registers to enable or disable 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.

PRODUCT FEATURES

• Supports Pentium, Pentium II, AMD and Cyrix CPUs with I2C.

• 3 CPU clocks

• 14 SDRAM clocks for 3 DIMMs

• 7 PCI synchronous clocks.

• Optional single or mixed supply: All Vdd = 3.3V or Other s Vdd = 3.3V, VddLCPU=2.5V

• 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

• I2C 2-Wire serial interface and I2C read back

• 0.5%, 0.75%center type, 0~0.5% down type spread spectrum to reduce EMI

• Programmable registers to enable/stop each output and select modes mode as Tri-state or Normal

• 48 MHz for USB

• 24 MHz for super I/O

• Packaged in 48-pin SSOP