CY2291FI

Clock Generators, PLLs, Frequency Synthesizers Overview

The CY2291FI is a three-PLL general-purpose EPROM programmable clock generator in a 20-pin SOIC package. It supports field programming and industrial temperature operation (-40°C to +85°C). Input frequencies range from 1 MHz to 30 MHz for reference clocks or 10 MHz to 25 MHz for crystals. Output frequency ranges are 76.923 kHz to 80 MHz at 5V and 76.923 kHz to 60.0 MHz at 3.3V. Supply voltage ranges are 4.5V–5.5V (5V mode) and 3.0V–3.6V (3.3V mode). Shutdown current is typically 10 µA, with battery backup support via VBATT.

Clock Generators, PLLs, Frequency Synthesizers Feature Summary

• Three integrated phase-locked loops (SPLL, CPLL, UPLL) for flexible clock generation
• EPROM programmability allowing custom output frequency configurations
• Smooth slewing capability on CPUCLK output for power management
• Configurable 3.3V or 5V operation with low-power shutdown modes

Clock Generators, PLLs, Frequency Synthesizers Applications

• PC motherboard clock generation
• Laptop and Green PC power management systems
• Synchronous system timing requirements

Clock Generators, PLLs, Frequency Synthesizers Procurement Notes

Verify the specific ordering suffix and factory-programmed parameters against the datasheet selector guide. Confirm that the device meets the required industrial temperature range and voltage specifications for the target application environment before finalizing procurement decisions.

Clock Generators, PLLs, Frequency Synthesizers Selection Notes

Select the CY2291FI when field programmability and industrial temperature ratings are required. Ensure input crystal or reference clock frequencies fall within the specified 1 MHz to 30 MHz range. Verify that the desired output frequencies are supported by the internal PLL divider options for the chosen supply voltage.

Clock Generators, PLLs, Frequency Synthesizers Part Context

The CY2291 series is part of Cypress Semiconductor's third-generation clock generator family, upwardly compatible with ICD2023 and ICD2028 standards. The CY2291FI specifically denotes the field-programmable variant designed for industrial temperature applications, offering customizable clock solutions for modern synchronous systems.

Clock Generators, PLLs, Frequency Synthesizers Replacement Considerations

CY2291F: Commercial temperature version. CY2291I: Industrial temperature, factory-programmable version. CY2291: Commercial temperature, factory-programmable version. Verify temperature range and programming method compatibility.