LTC6948IUFD-3#PBF

Clock Generators, PLLs, Frequency Synthesizers Overview

The LTC6948IUFD-3#PBF is a fractional-N phase-locked loop synthesizer with an integrated voltage-controlled oscillator (VCO) from Analog Devices. It operates within a VCO frequency range of 3.84 GHz to 5.79 GHz and supports output frequencies up to 6.39 GHz via a programmable divider. The device features a 4th-order delta-sigma modulator for low spurious performance, a reference input frequency up to 425 MHz, and an SPI interface. It requires a 3.15V to 3.45V supply for digital/reference sections and a 4.75V to 5.25V supply for the VCO and charge pump. Packaged in a 28-lead QFN.

Clock Generators, PLLs, Frequency Synthesizers Feature Summary

• Integrated VCO with a frequency range of 3.84 GHz to 5.79 GHz
• Advanced 4th-order delta-sigma modulator for ultralow spurious levels
• Programmable output divider with integer settings from 1 to 6
• Normalized in-band phase noise floor of -226 dBc/Hz

Clock Generators, PLLs, Frequency Synthesizers Applications

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

Clock Generators, PLLs, Frequency Synthesizers Procurement Notes

Verify the specific suffix '-3' corresponds to the required 3.84 GHz to 5.79 GHz VCO frequency band. Confirm that the operating environment remains within the specified -40°C to 105°C junction temperature range. Ensure power supply decoupling meets the datasheet requirements for the 3.3V and 5V rails to maintain phase noise specifications.

Clock Generators, PLLs, Frequency Synthesizers Selection Notes

Select this part when the target output frequency falls between 3.84 GHz and 5.79 GHz at O_DIV = 1. Consider the LTC6948IUFD-1, -2, or -4 variants if the application requires lower or higher fundamental VCO ranges. Verify that the system can accommodate the separate 3.3V and 5V power domains required for optimal performance.

Clock Generators, PLLs, Frequency Synthesizers Part Context

This component belongs to the LTC6948 family of ultralow noise fractional-N synthesizers. The 'I' designation indicates an industrial temperature range (-40°C to 105°C). The '#PBF' suffix denotes a lead-free finish compliant with RoHS standards. Other family members include the LTC6948IUFD-1, -2, and -4, which offer different internal VCO tuning ranges.

Clock Generators, PLLs, Frequency Synthesizers Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided documentation.