LTC6948IUFD-4#TRPBF

Clock Generators, PLLs, Frequency Synthesizers Overview

The LTC6948IUFD-4#TRPBF is a fractional-N phase-locked loop synthesizer with an integrated voltage-controlled oscillator (VCO), manufactured by Analog Devices. It operates in the 4.20 GHz to 6.39 GHz frequency range when the output divider is set to 1. The device features a fully integrated VCO, reference divider, phase-frequency detector, ultralow noise charge pump, and a fractional feedback divider utilizing a 4th-order delta-sigma modulator. Key electrical specifications include a reference input frequency up to 425 MHz, an output divider range of 1 to 6, and a normalized in-band phase noise floor of –226 dBc/Hz. It is housed in a 28-lead QFN package.

Clock Generators, PLLs, Frequency Synthesizers Feature Summary

• Integrated VCO with frequency range of 4.20 GHz to 6.39 GHz
• Ultralow noise performance with –226 dBc/Hz normalized in-band phase noise floor
• Advanced 4th-order delta-sigma modulator for exceptionally low spurious levels
• Programmable output divider with integer settings from 1 through 6

Clock Generators, PLLs, Frequency Synthesizers Applications

• Wireless basestations (LTE, WiMAX, W-CDMA, PCS)
• Microwave data links
• Military and secure radio systems
• Test and measurement equipment

Clock Generators, PLLs, Frequency Synthesizers Procurement Notes

Verify the specific ordering suffix #TRPBF indicates tape and reel packaging rather than tube packaging. Confirm that the -4 variant matches the required 4.20 GHz to 6.39 GHz operational frequency range for the design. Ensure compatibility with the 28-lead QFN footprint during procurement planning.

Clock Generators, PLLs, Frequency Synthesizers Selection Notes

Select the LTC6948IUFD-4 variant specifically for applications requiring output frequencies between 4.20 GHz and 6.39 GHz. Consider the output divider setting if lower frequency generation within this band is necessary. Verify that the system can support the required 5V supply for the VCO and charge pump circuits alongside the 3.3V logic supplies.

Clock Generators, PLLs, Frequency Synthesizers Part Context

This component belongs to the LTC6948 family of ultralow noise fractional-N synthesizers. The -4 suffix denotes the specific high-frequency version covering 4.20 GHz to 6.39 GHz. Other variants in the series include the -1, -2, and -3 models, which cover lower frequency ranges down to 0.373 GHz depending on the output divider configuration.

Clock Generators, PLLs, Frequency Synthesizers Replacement Considerations

Direct replacements within the same family include the LTC6948IUFD-1#TRPBF, LTC6948IUFD-2#TRPBF, and LTC6948IUFD-3#TRPBF, provided their respective frequency ranges meet the application requirements. These parts share identical pinouts and functionality but differ in internal VCO tuning characteristics.