GENERAL DESCRIPTION

The W83193R-02/-04/-04A is a Main board Clock Synthesizer which provides all clocks required for high-speed RISC or CISC microprocessor such as Intel PentiumPro, PentiumII, AMD or Cyrix. Eight different frequency of CPU and PCI clocks are externally selectable with smooth transitions.

FEATURES

• Supports PentiumÔ, PentiumÔ Pro, PentiumÔ II, AMD and Cyrix CPUs with I2C.

• 4 CPU clocks

• 12 SDRAM clocks for 3 DIMs.

• 7 PCI synchronous clocks.

• One IOAPIC clock for multiprocessor support.

• Optional single or mixed supply: (VDD = VDDq3 = VDDq2 = VDDq2b = 3.3V) or (VDD = VDDq3 = 3.3V, VDDq2 = VDD2b = 2.5V)

• < 250 pS skew among CPU and SDRAM clocks.

• < 250 pS skew among PCI clocks.

• Smooth frequency switch with selections from 50 MHz to 83.3 MHz CPU. (W83193R-04)

• Smooth frequency switch with selections from 50 MHz to 112 MHz CPU. (W83193R-04A)

• I2C 2-Wire serial interface and I2C read back.

• Spread spectrum function to reduce EMI.

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

• MODE pin for power Management

• 48 MHz for USB

• 24 MHz for super I/O

• Packaged in 48-pin SSOP