ICS9169C-231

• 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

Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . .7.0 V
Logic Inputs . . . . . . . . . . . . . . . . . . . . . . . . . .GND 0.5 V to VDD +0.5 V
Ambient Operating Temperature . . . . . . . . . . 0°C to +70°C
Storage Temperature . . . . . . . . . . . . . . . . . . .65°C to +150°C


Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. These ratings are stress specifications only and functional operation of the device at these or any other conditions above those listed in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect product reliability.

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.

Either synchronous (CPU/2) or asynchronous (32 MHz) PCI bus operation can be selected by latching data on BSEL input