General Description

The ICS9169C-231 is a low-cost frequency generator designed specifically for Pentium and Pentium-Pro based chip set systems. The integrated buffer minimizes skew and provides all the clocks required. A 14.318 MHz XTAL oscillator provides the reference clock to generate standard Pentium frequencies. The CPU clock makes gradual frequency transitions without violating the PLL timing of internal microprocessor clock multipliers. A raised frequency setting of 68.5 MHz is available for Turbo-mode of the 66.8 MHz CPU. The ICS9169C-231 contains 8 CPU clocks, 6 PCI clocks, 1 REF at 48MHz and 1 at 24MHz.

Features

• Eight selectable CPU clocks operate up to 83.3 MHz

• Frequency selections include Turbo-mode speed of 68.5 MHz

• Maximum CPU jitter of ±200ps

• Six BUS clocks support sync or async bus operation

• 250ps skew window for CPU outputs, 500ps skew window for BUS outputs

• CPU clocks to BUS clocks skew 1-4 ns (CPU early)

• 48 MHz clock for USB support & 24 MHz clock for FD.

• Logic inputs latched at Power-On for frequency selection saving pins as Input/Output

• Integrated buffer outputs drive up to 30pF loads

• 3.0V - 3.7V supply range, CPU (1:8) outputs 2.5V (2.375 - 2.6V) VDD option

• 28-pin SOIC or SSOP package