General Description
The ICS9148-49 is part of a reduced pin count two-chip clock solution for designs using an Intel BX style chipset. Companion SDRAM buffers are ICS9179-03, -04 and -12.
There are two PLLs, with the first PLL capable of spread spectrum operation. Spread spectrum typically reduces system EMI by 8-10dB. The second PLL provides support for USB 48MHz requirements. CPU frequencies up to 100MHz are supported.
FEATUREs
• 3CPUs @2.5V, up to 100MHz.
• 7PCIs @3.3V(including 1 free running, 1 Early).
• 1-48MHz(@3.3V) fixed.
• 1 REF(3.3V, 14.318MHz), 1 IOAPIC(2.5V, 14.318MHz)
• Strong REF clock (1V/ns @ 50pf load)
• Excellent power management features including Power down, PCI and CPU stops
• Spread Spectrum for EMI control(0.5% down spread)
• Early PCI (3.0ns –250ps)