The ICS9150-04 generates all clocks required for high speed RISC or CISC microprocessor systems such as Intel PentiumPro or Cyrix. Eight different reference frequency multiplying factors are selectable from 50 to 83.3MHz. Features include five CPU, seven PCI and Sixteen SDRAM clocks. One reference output is available equal to the crystal frequency, plus three IOAPIC outputs powered by VDDL1. One 48 MHz for USB is provided plus a 24 MHz. Spread Spectrum built in up to 1.5% modulation to reduce EMI. Serial programming I2C interface allows changing functions, stop clock programing and Frequency selection. Rise time adjustment for VDD at 3.3V or 2.5V CPU. Additionally, the device meets the Pentium power-up stabilization, which requires that CPU and PCI clocks be stable within 2ms after power-up.