1. Products
  2. RF and Microwave
  3. Phase Locked Loop (PLL) Synthesizer & Translation Loop
  4. Integer-N PLL
  5. LTC6946

Alternative Parts


Features and Benefits

  • Low Noise Integer-N PLL with Integrated VCO
  • –226dBc/Hz Normalized In-Band Phase Noise Floor
  • –274dBc/Hz Normalized In-Band 1/f Noise
  • –157dBc/Hz Wideband Output Phase Noise Floor
  • Excellent Spurious Performance
  • Output Divider (1 to 6, 50% Duty Cycle)
  • Output Buffer Muting
  • Low Noise Reference Buffer
  • Charge Pump Current Adjustable from 250μA to 11.2mA
  • Configurable Status Output
  • SPI Compatible Serial Port Control
  • PLLWizard Software Design Tool Support

Product Details

The LTC6946 is a high performance, low noise, 6.39GHz phase-locked loop (PLL) with a fully integrated VCO, including a reference divider, phase-frequency detector (PFD) with phase-lock indicator, ultralow noise charge pump, integer feedback divider, and VCO output divider. The charge pump contains selectable high and low voltage clamps useful for VCO monitoring.

The integrated low noise VCO uses no external components. It is internally calibrated to the correct output frequency with no external system support.

The part features a buffered, programmable VCO output divider with a range of 1 through 6, providing a wide frequency range.

Frequency Coverage Options
LTC6946-1 LTC6946-2 LTC6946-3 LTC6946-4
0 DIV = 1 2.240 to 3.740 3.080 to 4.910 3.840 to 5.790 4.200 to 6.390
0 DIV = 2 1.120 to 1.870 1.540 to 2.455 1.920 to 2.895 2.100 to 3.195
0 DIV = 3 0.747 to 1.247 1.027 to 1.637 1.280 to 1.930 1.400 to 2.130
0 DIV = 4 0.560 to 0.935 0.770 to 1.228 0.960 to 1.448 1.050 to 1.598
0 DIV = 5 0.448 to 0.748 0.616 to 0.982 0.768 to 1.158 0.840 to 1.278
0 DIV = 6 0.373 to 0.623 0.513 to 0.818 0.640 to 0.965 0.700 to 1.065


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

Product Lifecycle icon-not-recommended Last Time Buy

All products in this family will be obsolete soon. Please contact ADI Sales or Distributors to arrange for final purchases and read our Obsolescence Information to review the time periods for placing final orders and receiving final shipments.

Evaluation Kits (5)

Documentation & Resources

  • View All (14)
  • Data Sheet (1)
  • Reliability Data (1)
  • Application Note (1)
  • User Guide (1)
  • Design Note (1)
  • Product Selector Card (1)
  • Solutions Bulletin & Brochure (1)
  • Technical Article (6)
  • Video (1)
  • Software & Systems Requirements

    Evaluation Software


    PLLWizard is used to communicate with the LTC6945 and LTC6946 synthesizers. It uses the DC590 controller to translate between USB and SPI-compatible serial communications formats. It also includes advanced PLL design and simulation capabilities which aid in loop filter design and selecting the correct SPI map register values.

    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


    IBIS Model

    Design Tool


    ADIsimPLL enables the rapid and reliable evaluation of new high performance PLL products from ADI. It is the most comprehensive PLL Synthesizer design and simulation tool available today. Simulations performed include all key non-linear effects that are significant in affecting PLL performance. ADIsimPLL removes at least one iteration from the design process, thereby speeding the design- to-market.

    Product Recommendations

    LTC6946 Companion Parts

    Recommended D/A Converters

    Recommended Reference Buffer

    • With integrated filters for improved noise: LTC6957.

    Recommended Reference Clean Up PLL

    Recommended Related Parts

    Recommended Suggested Oscillator

    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.View our quality and reliability program and certifications for more information.

    Part Number Material Declaration Reliability Data Pin/Package Drawing CAD Symbols, Footprints & 3D Models
    LTC6946IUFD-1#PBF Material Declaration Reliability Data 28-Lead QFN (4mm x 5mm x 0.75mm w/ EP)
    LTC6946IUFD-4#TRPBF Material Declaration Reliability Data 28-Lead QFN (4mm x 5mm x 0.75mm w/ EP)
    Wafer Fabrication Data R565 Reliability Data

    PCN-PDN Information

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    Sample & Buy

    Ordering FAQs

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    Buy Now Pricing

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    List Pricing

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    Evaluation Boards

    Pricing displayed is based on 1-piece.

    Up to two boards can be purchased through Analog.com. 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.