SI5351C-A-GU

Clock Generators, PLLs, Frequency Synthesizers Overview

The SI5351C-A-GU is an I2C-programmable CMOS clock generator from Silicon Labs, designed to replace crystals, oscillators, and PLLs. It generates up to eight non-integer-related frequencies ranging from 8 kHz to 160 MHz with 0 ppm error using a PLL/MultiSynth architecture. The device synchronizes to an external reference clock (CLKIN) inputting 10–100 MHz. It features separate core (VDD: 2.5/3.3 V) and output (VDDO: 1.8/2.5/3.3 V) supplies, low period jitter (100 ps pk-pk typical), and configurable spread spectrum. Packaged in a 24-QSOP, it supports glitchless frequency changes and static phase offsets.

Clock Generators, PLLs, Frequency Synthesizers Feature Summary

• Generates up to eight independent clock outputs with zero ppm synthesis error
• Synchronizes to external reference clock inputs for precise timing alignment
• Features highly linear VCXO architecture and programmable rise/fall times
• Supports configurable spread spectrum modulation for EMI reduction

Clock Generators, PLLs, Frequency Synthesizers Applications

• HDTV and DVD/Blu-ray systems
• Networking and communication equipment
• Servers and storage devices
• Printers, scanners, and projectors

Clock Generators, PLLs, Frequency Synthesizers Procurement Notes

Verify the specific package type and operating temperature range against the datasheet specifications before procurement. Confirm that the external reference clock signal levels are compatible with the CLKIN input requirements. Ensure proper decoupling capacitors are placed near the VDD and VDDO pins to maintain signal integrity and power supply stability during operation.

Clock Generators, PLLs, Frequency Synthesizers Selection Notes

Select this model when synchronization to an external clock source is required rather than free-running generation. Compare the 24-QSOP package dimensions against board space constraints relative to QFN or MSOP alternatives. Evaluate the need for multiple independent voltage domains if different output logic levels are necessary for downstream components.

Clock Generators, PLLs, Frequency Synthesizers Part Context

This component belongs to the Si5351 family of clock generators. The 'C' variant specifically denotes support for an external clock input (CLKIN). The 'A' suffix indicates standard performance characteristics without factory-customized EMI profiles. The 'GU' suffix identifies the 24-pin QSOP package option within the product line.

Clock Generators, PLLs, Frequency Synthesizers Replacement Considerations

Si5351C-B-GM

Clock Generators, PLLs, Frequency Synthesizers FAQ

What is the maximum frequency supported by the Si5351C?

The device can generate output frequencies up to 160 MHz.

How does the Si5351C handle clock synchronization?

It synchronizes to an external reference clock applied to the CLKIN pin, which accepts frequencies between 10 MHz and 100 MHz.

Can the output voltage levels be adjusted independently?

Yes, separate output supply pins (VDDO) allow each bank of outputs to operate at 1.8 V, 2.5 V, or 3.3 V.