General Description

The ICS9148-46 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, 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) and 24MHz requirements. CPU frequencies up to 100MHz are supported.

Features

• Generates system clocks for CPU, PCI, 14.314 MHz, 48 and 24MHz.

• Supports single or dual processor systems

• Skew from CPU (earlier) to PCI clock 1 to 4ns

• Separate 2.5V and 3.3V supply pins

• 2.5V outputs: CPU

• 3.3V outputs: PCI, REF

• No power supply sequence requirements

• 28 pin SSOP

• Spread Sectrum operation optional for PLL1

• CPU frequencies to 100MHz are supported.