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CY24239
Spread Spectrum Frequency Timing Generator
Features
• Maximized EMI Suppression using Cypress’s Spread Spectrum Technology • –1.2% and –2.4% Spread Spectrum support • Three copies of CPU output • Seven copies of PCI output • One 48-MHz output for USB / One 24-MHz for SIO • Two buffered reference outputs • Two IOAPIC outputs • Seventeen SDRAM outputs provide support for 4 DIMMs • SMBus interface for programming • Power management control inputs Table 2. Pin Selectable Frequency Input Address CPU_F, CPU1:2 FS3 FS2 FS1 FS0 (MHz) 1 1 1 1 91.66 1 1 1 0 75.0 1 1 0 1 100.0 1 1 0 0 83.3 1 0 1 1 66.6 1 0 1 0 105.0 1 0 0 1 110.0 1 0 0 0 133.3 0 1 1 1 91.66 0 1 1 0 75.0 0 1 0 1 100.0 0 1 0 0 83.3 0 0 1 1 91.66 0 0 1 0 75.0 0 0 0 1 100.0 0 0 0 0 83.