LMX2694SRTCTSEP

Clock Generators, PLLs, Frequency Synthesizers Overview

The LMX2694-SEP is a radiation-hardened wideband phase-locked loop (PLL) synthesizer with an integrated voltage-controlled oscillator (VCO). It generates output frequencies from 39.3 MHz to 15.1 GHz without requiring external doublers or harmonic filters. The device operates on a single 3.3-V supply and supports up to 200-MHz phase detector frequency. Key electrical specifications include –110 dBc/Hz phase noise at 100-kHz offset for a 15-GHz carrier, 54-fs RMS jitter at 8 GHz, and a figure of merit of –236 dBc/Hz. It withstands total ionizing doses up to 30 krad(Si) and single event latch-up events exceeding 43 MeV-cm²/mg.

Clock Generators, PLLs, Frequency Synthesizers Feature Summary

• Radiation hardening designed for space environments with high tolerance to ionizing dose and single event effects.
• Integrated VCO covers the full frequency range down to 39.3 MHz, eliminating the need for external frequency doublers.
• Supports deterministic phase synchronization across multiple devices using SYNC and SYSREF inputs.
• Features ultra-fast VCO calibration suitable for applications requiring abrupt frequency changes.

Clock Generators, PLLs, Frequency Synthesizers Applications

• Command and data handling systems
• Communications payloads
• Optical imaging payloads
• Radar imaging payloads
• Aerospace and defense electronics

Clock Generators, PLLs, Frequency Synthesizers Procurement Notes

Verify the specific ordering suffix against the manufacturer's official documentation to ensure correct package type and temperature rating. Confirm that the component meets the required radiation hardness levels for the intended mission profile. Check for any recent production lifecycle notices or obsolescence warnings directly from Texas Instruments before finalizing procurement plans.

Clock Generators, PLLs, Frequency Synthesizers Selection Notes

Select this component when designing systems requiring high-frequency synthesis in harsh radiation environments. Ensure the design accommodates the 3.3-V single supply requirement and the thermal dissipation needs of the VQFN package. Verify that the reference input signal characteristics align with the device's AC coupling requirements and maximum input frequency limits.

Clock Generators, PLLs, Frequency Synthesizers Part Context

This part belongs to the LMX2694 family of PLLatinum RF synthesizers. The -SEP suffix indicates a special engineering lot variant specifically qualified for radiation tolerance. It shares functional similarities with commercial counterparts but includes hardened structures to prevent latch-up and performance degradation in space environments.

Clock Generators, PLLs, Frequency Synthesizers Replacement Considerations

Direct replacements must match the radiation hardness specifications. Commercial equivalents like the standard LMX2694 lack the necessary radiation tolerance. Verify pin compatibility and software register maps if substituting within the same product family.

Clock Generators, PLLs, Frequency Synthesizers FAQ

Does the LMX2694-SEP require an external frequency doubler?

No, the integrated VCO covers the entire frequency range down to 39.3 MHz, eliminating the need for external doublers or harmonic filters.

What is the maximum total ionizing dose the device can withstand?

The device is rated to withstand a total ionizing dose of up to 30 krad(Si).

Can the device synchronize the phase of multiple units?

Yes, the device supports phase synchronization across multiple instances using the SYNC pin to achieve deterministic phase relationships.