LTC6946IUFD-2#PBF

Clock Generators, PLLs, Frequency Synthesizers Overview

The LTC6946IUFD-2#PBF is an ultralow noise and spurious integer-N synthesizer with an integrated VCO, covering a frequency range of 3.08 GHz to 4.91 GHz. It features a fully integrated phase-locked loop (PLL) including a reference divider, phase-frequency detector, charge pump, and output divider. The device offers –226 dBc/Hz normalized in-band phase noise floor and –274 dBc/Hz normalized in-band 1/f noise. It operates on supply voltages of 3.15V to 3.45V for digital/RF sections and 4.75V to 5.25V for the VCO and charge pump. The component is housed in a 28-lead QFN package.

Clock Generators, PLLs, Frequency Synthesizers Feature Summary

• Integrated low-noise VCO with no external components required
• Programmable output divider ranging from 1 to 6
• Adjustable charge pump current from 250µA to 11.2mA
• SPI-compatible serial port control with configurable status output

Clock Generators, PLLs, Frequency Synthesizers Applications

• Wireless base stations (LTE, WiMAX, W-CDMA, PCS)
• Broadband wireless access systems
• Military and secure radio communications
• Test and measurement equipment

Clock Generators, PLLs, Frequency Synthesizers Procurement Notes

Verify the specific suffix #PBF indicates lead-free finish and tube packaging. Confirm the -2 variant matches the required 3.08GHz to 4.91GHz VCO frequency range. Check for RoHS compliance documentation and ensure the operating temperature range of –40°C to 105°C meets system requirements.

Clock Generators, PLLs, Frequency Synthesizers Selection Notes

Select this model when the target RF output frequency falls within the 3.08 GHz to 4.91 GHz range at output divider setting 1. Consider the LTC6946-1, -3, or -4 if frequencies outside this band are needed. Ensure sufficient thermal management via the exposed pad soldering to maintain junction temperature below 105°C under maximum load conditions.

Clock Generators, PLLs, Frequency Synthesizers Part Context

This part belongs to the LTC6946 family of integer-N synthesizers. The -2 designation specifically defines the internal VCO tuning range compared to other variants like the -1 (2.24–3.74 GHz), -3 (3.84–5.79 GHz), and -4 (4.20–6.39 GHz). All variants share identical pinouts, control interfaces, and electrical characteristics except for the VCO frequency coverage.

Clock Generators, PLLs, Frequency Synthesizers Replacement Considerations

Publicly confirmed substitute part numbers are not available in the provided datasheet. Designers should consult Analog Devices marketing for alternative recommendations or verify compatibility with existing board layouts if considering cross-model variants within the same family.