LMX2571SRHHTEP

Clock Generators, PLLs, Frequency Synthesizers Overview

The LMX2571SRHHTEP is a low-power, high-performance PLLatinum RF synthesizer featuring integrated delta-sigma fractional-N PLL and multiple core VCOs. It generates frequencies from 10 MHz to 1344 MHz with phase noise of -123 dBc/Hz at 12.5-kHz offset and -145 dBc/Hz at 1-MHz offset at 480 MHz. The device operates within an extended temperature range of -55 °C to +125 °C and consumes 39 mA in synthesizer mode. It includes a dedicated 5-V charge pump for external VCO operation and supports direct digital FSK modulation.

Clock Generators, PLLs, Frequency Synthesizers Feature Summary

• Integrated FastLock technique reduces frequency switching time to less than 1.5 ms even with narrow loop bandwidths.
• Programmable multiplier in the R-divider eliminates integer boundary spurs and increases phase detector frequency.
• Supports direct digital FSK modulation with discrete levels or arbitrary level pulse shaping via pins or SPI.

Clock Generators, PLLs, Frequency Synthesizers Applications

• Seeker front end
• Defense radio
• Aircraft cockpit display

Clock Generators, PLLs, Frequency Synthesizers Procurement Notes

Verify the VID number V62/21613-01XE to confirm this specific enhanced product variant. Ensure the application environment accommodates the specified -55 °C to +125 °C operating temperature range. Confirm that the system design accounts for the absence of the TrCtl and OSCin* pins compared to standard commercial versions.

Clock Generators, PLLs, Frequency Synthesizers Selection Notes

Select this component when wideband coverage up to 1344 MHz and low power consumption are required. Use the internal VCO for compact designs or the external VCO mode utilizing the 5-V charge pump for higher frequency flexibility. Verify compatibility with MICROWIRE interface requirements and ensure appropriate loop filter design for the desired lock time and phase noise performance.

Clock Generators, PLLs, Frequency Synthesizers Part Context

This part belongs to the LMX2571-EP family, distinguished by its extended industrial temperature rating and specific pinout modifications. Unlike the standard LMX2571, it lacks the TrCtl pin and does not support differential reference input or crystal oscillator modes. It is designed for robust performance in demanding environments.

Clock Generators, PLLs, Frequency Synthesizers Replacement Considerations

LMX2571NJKR serves as a commercial alternative but operates within a limited -40 °C to +85 °C temperature range and lacks the extended environmental specifications of the EP version.

Clock Generators, PLLs, Frequency Synthesizers FAQ

Does the LMX2571SRHHTEP support differential reference input?

No, the LMX2571-EP does not support differential mode; Pin 36 is a no-connect pin, and only single-ended CMOS clock driving is supported on the OSCin pin.

What is the maximum output frequency achievable?

The device provides a continuous output frequency range from 10 MHz to 1344 MHz using its integrated VCO cores and output dividers.

How does the device handle external VCO operation?

It features a dedicated 5-V charge pump and output divider specifically for external VCO configurations, eliminating the need for an external op-amp.