Alternative Parts


Features and Benefits

  • Low Noise Integer-N PLL with Integrated VCO
  • Output Jitter:
    • 90fs RMS (12kHz to 20MHz)
    • 115fs RMS (ADC SNR Method)
  • Noise Floor = –165dBc/Hz at 250MHz
  • EZSync, ParallelSync Multichip Synchronization
  • SYSREF Generation for JESD204B/JESD204C, Subclass 1
  • Output Frequency Range:
    • 1.95MHz to 2.5GHz (LTC6951)
    • 2.1MHz to 2.7GHz (LTC6951-1)
  • –229dBc/Hz Normalized In-Band Phase Noise Floor
  • –277dBc/Hz Normalized In-Band 1/f Noise
  • Five Independent, Low Noise Outputs
  • Reference Input Frequency up to 425MHz
  • LTC6951Wizard Software Design Tool Support
  • –40°C to 105°C Operating Junction Temperature Range

Product Details

The LTC6951 is a high performance, low noise, Phase Locked Loop (PLL) with a fully integrated VCO. The low noise VCO uses no external components and is internally calibrated to the correct output frequency with no external system support.

The clock generation section provides five outputs based on the VCO prescaler signal with individual dividers for each output. Four outputs feature very low noise, low skew CML logic. The fifth output is low noise LVDS. All outputs can be synchronized and set to precise phase alignment using the programmable delays.

Choose the LTC6951-1 if any desired output frequency falls in the ranges 2.5GHz to 2.7GHz, 1.66GHz to 1.8GHz, or 1.25GHz to 1.35GHz. Choose the LTC6951 for all other frequencies.


  • High Performance Data Converter Clocking
  • Wireless Infrastructure
  • Test and Measurement

Product Lifecycle icon-recommended Recommended for New Designs

This product has been released to the market. The data sheet contains all final specifications and operating conditions. For new designs, ADI recommends utilization of these products.

Evaluation Kits (4)

Tools & Simulations


Linduino is Analog Devices’ Arduino compatible system for developing and distributing firmware libraries and example code for our integrated circuits. Each Linduino-supported product includes an example main program, defined in the LTSketchbook/Part Number folder and driver code, defined in the LTSketchbook/libraries folder.

Linduino code repository on GitHub and instructions on how to use the code.

Purchase Linduino


Product Recommendations

LTC6951 Companion Parts

Recommended ADCs

Recommended Clock Distribution Device

Recommended Reference Buffer

  • With integrated filters for improved noise: LTC6957.

Recommended Reference Clean Up PLL

Design Resources

ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well.  "Zero defects" for shipped products is always our goal.

Sample & Buy

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Evaluation Boards

Pricing displayed is based on 1-piece.

Up to two boards can be purchased through To order more than two, please purchase through one of our listed distributors.

Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.