ICS9248-77 Overview
The ICS9248-77 is a main clock synthesizer chip for Pentium II based systems using Rambus Interface DRAMs. This chip provides all the clocks required for such a system when used with a Direct Rambus Clock Generator(DRCG) chip such as the ICS9212-01. Spread Spectrum may be enabled by driving the SPREAD# pin active.
ICS9248-77 Key Features
- CPUs @ 2.5V, up to 150MHz
- IOAPIC @ 2.5V, PCI or PCI/2
- 3V66MHz @ 3.3V
- PCIs @ 3.3V
- 48MHz, @ 3.3V fixed
- 24MHz, @ 3.3V fixed
- CPU/2, @ 2.5V. ± .25% center spread, or 0 to -.5% down spread. Uses external 14.318MHz crystal
- 120K ohm pull-up to VDD on indicated inputs
- 1.5ns (CPU leads) 3V66 to PCI Output Offset: 1.5
- 4.0ns (3V66 leads) CPU to IOAPIC Output Offset 1.5
