ICS9147-01

Integrated Circuit Systems, Inc. ICS9147-01 Frequency Generator & Integrated Buffers for PENTIUMTM General Description The ICS9147-01 generates all clocks required for high speed RISC or CISC microprocessor systems such as Intel PentiumPro. Two bidirectional I/O pins (FS1,FS2) are latched at power-on to the functionality table, with FS0 selectable in real-time to toggle between conditions. The inputs provide for tristate and test mode conditions to aid in system level testing. These multiplying factors can be customized for specific applications. Glitch-free stop clockcontrols are provided for CPU clocks and BUS clocks. High drive BUS and SDRAM outputs typically provide greater than 1 V/ns slew rate into 30 pF loads. CPU outputs typically provide better than 1V/ns slew rate into 20 pF loads while maintaining 50 ± 5% duty cycle. The REF clock outputs typically provide better than 0.5V/ns slew rates. Seperate buffers supply pins VDD2 allow for 3.3V or reduced voltage swing (from 2.9 to 2.5V) for CPU (1:4) and IOAPIC outputs. Features Four copies of CPU clock Six SDRAM (3.3 V TTL), usable as AGP clocks Seven copies of BUS clock (synchronous with CPU clock/2 or CPU/2.5 for 75 and 83.3 MHz CPU) CPU clocks to BUS clocks skew 1-4ns (CPU early) One IOAPIC clock @14.31818 MHz Two copies of Ref. clock @14.31818 MHz One each 48/ 24 MHz (3.3 V TTL) This device is configured into the Mobile mode for power management of Intel 430 TX Ref. 14.31818 MHz Xtal osc...