CYIFS781BZXC

Clock Generators, PLLs, Frequency Synthesizers Overview

The CYIFS781BZXC is a low EMI Spread Spectrum Clock Generator (SSCG) manufactured by Cypress Semiconductor Corp. It operates within a frequency range of 6 MHz to 82 MHz and provides a 1× modulated clock output at the FSOUT pin. The device supports power supply voltages from 3V to 5V, with typical power dissipation of 37 mW at 3.3 VDC and 115 mW at 5.0 VDC. It utilizes an external R-C loop filter for programmable modulation bandwidths ranging from 1.0% to 4.0%. The component is housed in an 8-pin TSSOP package with a 4.4 mm body width and functions over a commercial temperature range of 0°C to 70°C.

Clock Generators, PLLs, Frequency Synthesizers Feature Summary

• Generates spread spectrum clocks using center-spread modulation to reduce electromagnetic interference peaks at fundamental and harmonic frequencies.
• Features a simple external loop filter configuration allowing programmable modulation bandwidth selection between 1.0% and 4.0%.
• Accepts input frequencies from 6 MHz to 82 MHz via crystal or TTL/CMOS source and outputs a synchronized modulated signal.

Clock Generators, PLLs, Frequency Synthesizers Applications

• Desktop and notebook computers
• Printers, copiers, and multifunction printers (MFP)
• LCD displays and monitors
• Networking equipment including LAN/WAN systems

Clock Generators, PLLs, Frequency Synthesizers Procurement Notes

Verify the specific ordering suffix against the manufacturer's official documentation to confirm package type and lead-free status. Ensure the required modulation bandwidth aligns with the recommended loop filter values provided in the datasheet tables for the selected operating voltage. Confirm that the application environment remains within the specified commercial temperature limits.

Clock Generators, PLLs, Frequency Synthesizers Selection Notes

Select this component when EMI reduction is critical for digital systems operating below 82 MHz. Choose based on the required output scaling; this part provides a 1× output relative to the input frequency. Designers must calculate the appropriate external loop filter components to achieve the desired spread percentage. Verify compatibility with the system's reference clock source, whether it be a crystal oscillator or a direct drive signal.

Clock Generators, PLLs, Frequency Synthesizers Part Context

This part belongs to the FS78x family of Spread Spectrum Clock Generators, which includes variants offering 2× and 4× frequency multiplication. The CYIFS781BZXC specifically denotes the lead-free version of the FS781 in the TSSOP package. Other family members like the FS782 and FS784 provide higher frequency outputs but share similar control logic and modulation principles.

Clock Generators, PLLs, Frequency Synthesizers Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation.