LTC6946IUFD-4#PBF

Clock Generators, PLLs, Frequency Synthesizers Overview

The LTC6946IUFD-4#PBF is an integer-N phase-locked loop with a fully integrated VCO, covering a frequency range of 4.20GHz to 6.39GHz at output divider setting 1. It features a programmable output divider (1–6), adjustable charge pump current (250µA to 11.2mA), and low noise reference buffer. The device operates on 3.3V digital/RF supplies and 5V VCO/charge pump supplies. Key electrical characteristics include –226dBc/Hz normalized in-band phase noise floor and –274dBc/Hz normalized 1/f noise. It supports SPI control and includes status outputs for lock detection.

Clock Generators, PLLs, Frequency Synthesizers Feature Summary

• Integrated VCO with frequency coverage from 4.20GHz to 6.39GHz (O_DIV=1)
• Programmable output divider ranging from 1 to 6
• Adjustable charge pump current from 250µA to 11.2mA
• Normalized in-band phase noise floor of –226dBc/Hz

Clock Generators, PLLs, Frequency Synthesizers Applications

• Wireless Base Stations (LTE, WiMAX, W-CDMA, PCS)
• Broadband Wireless Access
• Military and Secure Radio
• Test and Measurement

Clock Generators, PLLs, Frequency Synthesizers Procurement Notes

Verify the specific suffix -4#PBF corresponds to the 4.20GHz to 6.39GHz frequency band option. Confirm the UFD package type matches the 28-lead QFN requirement. Ensure supply voltages align with the specified 3.3V and 5V rails during integration.

Clock Generators, PLLs, Frequency Synthesizers Selection Notes

Select this variant when the target RF output frequency falls within the 4.20GHz to 6.39GHz range at O_DIV=1. Consider lower variants (-1, -2, -3) if operating at lower frequencies to optimize performance. Verify that the required output frequency can be achieved with the available output divider settings (1–6).

Clock Generators, PLLs, Frequency Synthesizers Part Context

The LTC6946 family consists of four variants differentiated by their integrated VCO frequency ranges. The -4 variant specifically covers the highest frequency band among the options. All variants share identical pinouts, control interfaces, and core PLL architecture, differing only in the calibrated VCO tuning range.

Clock Generators, PLLs, Frequency Synthesizers Replacement Considerations

Publicly confirmed substitute part numbers are not provided in the datasheet. Direct replacements must match the 28-lead QFN package, 4.20–6.39GHz frequency range, and 3.3V/5V supply requirements.