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ICS9248-55
Pentium/Pro/IITM System Clock Chip
General Description
The ICS9248-55 is a Clock Synthesizer chip for Pentium and PentiumPro CPU based Desktop/Notebook systems that will provide all necessary clock timing.
Features include four CPU and eight PCI clocks. Three reference outputs are available equal to the crystal frequency. Additionally, the device meets the Pentium power-up stabilization requirement, assuring that CPU and PCI clocks are stable within 2ms after power-up.
PD# pin enables low power mode by stopping crystal OSC and PLL stages. Other power management features include CPU_STOP#, which stops CPU (0:3) clocks, and PCI_STOP#, which stops PCICLK (0:6) clocks.
High drive CPUCLK outputs typically provide greater than 1 V/ns slew rate into 20pF loads.