SI5345B-B04421-GM

Clock Generators, PLLs, Frequency Synthesizers Overview

The Skyworks SI5345B-B04421-GM is a low-jitter, 10-output clock multiplier and jitter attenuator. It utilizes fourth-generation DSPLL and MultiSynth technologies to generate any frequency combination from any input source. The device supports differential inputs up to 750 MHz and LVCMOS inputs up to 250 MHz. Output frequencies range from 100 Hz to 350 MHz for differential formats and 100 Hz to 250 MHz for LVCMOS. It operates on a single 1.8 V core supply (VDD) and a 3.3 V analog supply (VDDA), with independent output supplies configurable at 3.3 V, 2.5 V, or 1.8 V. The component is housed in a 64-QFN package and functions within a temperature range of -40 °C to +85 °C.

Clock Generators, PLLs, Frequency Synthesizers Feature Summary

• Generates any combination of output frequencies from any input frequency using integer and fractional synthesis.
• Features ultra-low jitter performance of 90 fs rms with digitally programmable loop bandwidth.
• Supports hitless input clock switching between fractionally related sources.
• Includes in-circuit programmable non-volatile memory for known power-up configurations.

Clock Generators, PLLs, Frequency Synthesizers Applications

• OTN muxponders and transponders
• 10/40/100 G networking line cards
• GbE/10 GbE/100 GbE Synchronous Ethernet (ITU-T G.8262)
• Carrier Ethernet switches
• SONET/SDH line cards

Clock Generators, PLLs, Frequency Synthesizers Procurement Notes

Verify the specific ordering suffix against the manufacturer's current documentation to ensure compatibility with required factory preprogramming or configuration settings. Confirm that the selected part number matches the intended voltage levels and package requirements for your design. Cross-reference the datasheet revision date to validate all electrical specifications before finalizing procurement.

Clock Generators, PLLs, Frequency Synthesizers Selection Notes

Select this model when high channel count and flexible frequency synthesis are required. Ensure the application supports the specified 1.8 V core and 3.3 V analog supply rails. Verify that the external crystal frequency falls within the recommended 48 MHz to 54 MHz range for optimal jitter performance. Consider the ClockBuilder Pro software for efficient configuration of the serial interface and NVM settings.

Clock Generators, PLLs, Frequency Synthesizers Part Context

This component belongs to the Si5345 family, which offers 4 inputs and 10 outputs in a 64-QFN package. It is distinct from the Si5344 (4 outputs) and Si5342 (2 outputs) variants, which utilize a smaller 44-QFN package. The 'B' designation indicates a maximum output frequency limit of 350 MHz, differentiating it from the 'A' and 'C' variants that support higher frequencies up to 1028 MHz.

Clock Generators, PLLs, Frequency Synthesizers Replacement Considerations

Direct functional replacements within the same package include other Si5345B variants such as SI5345B-D-GMR or SI5345B-A-GM, provided the frequency range and preprogramming requirements align. Verify pin-to-pin compatibility and supply voltage specifications before substitution.