LTC6955IUKG#TRPBF

Clock Generators, PLLs, Frequency Synthesizers Overview

The LTC6955IUKG#TRPBF is an ultralow jitter, 7.5GHz fanout clock buffer featuring eleven CML outputs in a 52-lead QFN package. It utilizes a 4-pin parallel control port to configure between three and eleven active outputs or enable complete shutdown. The device supports output polarity inversion for alternating channels to facilitate multi-layer PCB routing. Additive output jitter is approximately 45fs RMS using the ADC SNR method and less than 5fs RMS within a 12kHz to 20MHz integration bandwidth at 7.5GHz. Operating junction temperature ranges from –40°C to 125°C with supply voltages of 3.15V to 3.45V.

Clock Generators, PLLs, Frequency Synthesizers Feature Summary

• Ultralow Jitter: ~45fs RMS (ADC SNR Method) and <5fs RMS (12kHz–20MHz BW at 7.5GHz)
• Parallel Control Port: Configures 3–11 outputs and enables output polarity inversion
• High Frequency Range: DC to 7.5GHz input and output capability
• CML Outputs: Eleven differential outputs with 100Ω differential output resistance

Clock Generators, PLLs, Frequency Synthesizers Applications

• High Performance Data Converter Clocking
• SONET, Fibre Channel, GigE Clock Distribution
• Low Skew and Jitter Clock and Data Fanout
• Wireless and Wired Communications

Clock Generators, PLLs, Frequency Synthesizers Procurement Notes

Verify the #TRPBF suffix indicates tape and reel packaging containing 2500 units. Confirm the I suffix denotes the industrial temperature range of –40°C to 125°C. Ensure the 52-lead UKG QFN package dimensions match the design footprint requirements.

Clock Generators, PLLs, Frequency Synthesizers Selection Notes

Select this component when multiple low-jitter CML clocks are required from a single source. Use the LTC6955-1 variant if a divide-by-2 output is needed for JESD204B SYSREF generation. Ensure input signals meet the minimum slew rate of 100 V/µs or utilize the FILT pin for lower slew rates.

Clock Generators, PLLs, Frequency Synthesizers Part Context

This part belongs to the LTC6955 family of high-performance fanout buffers. The standard LTC6955 provides eleven buffered outputs, while the LTC6955-1 replaces one output with a divide-by-2 divider. Both variants share identical electrical characteristics for the remaining ten outputs.

Clock Generators, PLLs, Frequency Synthesizers Replacement Considerations

Public confirmed substitute: HMC7043LP7FE.