CY26121ZC-21

Clock Generators, PLLs, Frequency Synthesizers Overview

The CY26121ZC-21 is a PacketClock Spread Spectrum Clock Generator manufactured by Cypress Semiconductor. It operates on a 3.3V supply and features an integrated phase-locked loop with modulation control for downspread applications at a nominal 30-kHz frequency. The device accepts a 25-MHz reference input via XIN or a parallel resonant crystal connected to XIN/XOUT. For the -21 suffix, the CLKSEL pin selects between 33.33 MHz (logic 0) and 25 MHz (logic 1) outputs. It utilizes a 15 pF crystal load capacitance and provides four clock outputs (CLKA through CLKD) in a 16-pin TSSOP package.

Clock Generators, PLLs, Frequency Synthesizers Feature Summary

• Integrated PLL with spread spectrum modulation control
• Selectable output frequencies based on configuration pin state
• Supports both driven reference and parallel resonant crystal inputs

Clock Generators, PLLs, Frequency Synthesizers Applications

• Spread spectrum clock generation for EMI reduction
• System timing distribution for complex digital designs
• Compatible with standard crystal oscillators or driven references

Clock Generators, PLLs, Frequency Synthesizers Procurement Notes

Verify the specific ordering suffix against the manufacturer's documentation to confirm package type, temperature grade, and reel options. Confirm that the component meets current design guidelines, as certain variants may be marked as not recommended for new designs. Ensure compatibility with the required crystal load capacitance specifications.

Clock Generators, PLLs, Frequency Synthesizers Selection Notes

Select this variant when a 25-MHz reference is required with selectable 33.33 MHz or 25 MHz outputs. Verify the system requires a 15 pF crystal load capacitance rather than the 6 pF option found in other suffixes. Check if the commercial temperature range of 0°C to 70°C satisfies the operational environment requirements.

Clock Generators, PLLs, Frequency Synthesizers Part Context

This component belongs to the CY26121 family of PacketClock generators. The ZC suffix indicates a 16-pin TSSOP package with commercial operating temperature. Other suffixes like ZI denote industrial temperature ranges, while numbers such as -2 or -3 indicate different default output frequencies and crystal load requirements.

Clock Generators, PLLs, Frequency Synthesizers Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided datasheet.