SI5351B-B05641-GM

Clock Generators, PLLs, Frequency Synthesizers Overview

The Skyworks SI5351B-B05641-GM is an I2C-programmable CMOS clock generator featuring a built-in Voltage-Controlled Crystal Oscillator (VCXO). It provides eight LVCMOS outputs in a 20-QFN package, generating non-integer-related frequencies from 2.5 kHz to 200 MHz with 0 ppm error. The device operates on a core supply of 2.25 V to 3.6 V and output supplies of 1.71 V to 3.6 V. It accepts a 25 MHz or 27 MHz crystal reference and supports spread spectrum modulation. Typical period jitter is less than 70 ps peak-to-peak.

Clock Generators, PLLs, Frequency Synthesizers Feature Summary

• Integrates a highly linear VCXO to eliminate the need for custom pullable crystals while supporting synchronous clock generation.
• Utilizes MultiSynth fractional dividers to generate up to eight independent, non-integer-related clock frequencies with zero frequency synthesis error.
• Features separate voltage supply pins for core logic and output buffers, enabling flexible level translation across different voltage domains.

Clock Generators, PLLs, Frequency Synthesizers Applications

• Replacing traditional crystals, crystal oscillators, and VCXOs in cost-sensitive designs
• Synchronous clock distribution in networking and communication equipment
• Clock generation for servers, storage systems, and residential gateways

Clock Generators, PLLs, Frequency Synthesizers Procurement Notes

Verify the factory preprogrammed configuration code 'B05641' matches the required frequency plan before integration. Confirm that the specific ordering suffix corresponds to the desired packaging format and ensure compatibility with the target system's I2C interface requirements.

Clock Generators, PLLs, Frequency Synthesizers Selection Notes

Select this variant when both free-running asynchronous clocks and synchronized VCXO-based outputs are required within a single component. Ensure the design accommodates the 20-QFN footprint and utilizes the internal load capacitance settings appropriate for the selected 25 MHz or 27 MHz reference crystal.

Clock Generators, PLLs, Frequency Synthesizers Part Context

This part belongs to the Si5351 family, which includes variants optimized for XTAL-only inputs (Si5351A) or external clock inputs (Si5351C). The Si5351B specifically adds the VCXO capability, allowing it to replace multiple PLLs or VCXOs locked to the same reference in complex timing architectures.

Clock Generators, PLLs, Frequency Synthesizers Replacement Considerations

Direct functional replacements include other Si5351B variants with different factory configurations or the Si5351A/C series if VCXO functionality is not required. Verify pinout compatibility and check for any changes in power consumption profiles between legacy components and this programmable generator.