CY2280PVXC-11ST

Application Specific Clock/Timing Overview

The CY2280PVXC-11ST is a clock synthesizer and driver designed for Pentium II and similar processor-based motherboards. It provides mixed 2.5V and 3.3V operation with four 2.5V CPU clocks up to 100 MHz, eight 3.3V synchronous PCI clocks, two 3.3V USB clocks at 48 MHz, three 3.3V reference clocks at 14.318 MHz, and two 2.5V APIC clocks. The device supports spread spectrum clocking for EMI reduction and operates within a supply voltage range of 2.375V to 3.465V across an ambient temperature range of 0°C to 70°C.

Application Specific Clock/Timing Feature Summary

• Mixed 2.5V and 3.3V operation supporting multiple clock domains
• Factory-EPROM programmable CPU clock frequencies and spread spectrum margins
• Integrated power management logic with glitch-free transitions
• Spread spectrum clocking capability for EMI control

Application Specific Clock/Timing Applications

• Pentium II processor-based motherboards
• Mobile or desktop PC systems
• Systems requiring SDRAM support when paired with CY231x

Application Specific Clock/Timing Procurement Notes

Verify the specific suffix 'X' against official documentation, as standard datasheets list 'CY2280PVC-11S'. Confirm package type is 48-pin SSOP (O48) and operating range is commercial grade. Ensure compatibility with required crystal load capacitance of 18 pF.

Application Specific Clock/Timing Selection Notes

Select based on required CPU frequency (66.6 MHz or 100 MHz) via SEL pins. Choose -11S option for downspread EMI reduction on CPU and PCI clocks. Ensure decoupling capacitors are placed close to each supply pin. Use parallel-resonant crystals with specified CLOAD for accurate frequency generation.

Application Specific Clock/Timing Part Context

The CY2280 series serves as a comprehensive clock solution for legacy Intel Pentium II platforms. It consolidates multiple clock outputs into a single 48-pin SSOP package, reducing board space compared to discrete solutions. The device integrates PLLs and drivers for CPU, PCI, USB, and APIC domains.

Application Specific Clock/Timing Replacement Considerations

Standard equivalents include CY2280PVC-11S. Verify functional compatibility regarding EPROM programming and pinout alignment before substitution.