Features and Benefits

  • Supports GR-1244 Stratum 3 stability in holdover mode
  • Supports smooth reference switchover with virtually
    no disturbance on output phase
  • Supports Telcordia GR-253 jitter generation, transfer, and
    tolerance for SONET/SDH up to OC-192 systems
  • Supports ITU-T G.8262 synchronous Ethernet slave clocks
  • Supports ITU-T G.823, G.824, G.825, and G.8261
  • Auto/manual holdover and reference switchover
  • Adaptive clocking allows dynamic adjustment of feedback dividers
    for use in OTN mapping/demapping applications
  • Dual digital PLL architecture with four reference inputs
    (single-ended or differential)
  • 4x2 crosspoint allows any reference input to drive either PLL
  • Input reference frequencies from 2 kHz to 1250 MHz
  • Reference validation and frequency monitoring (2 ppm)
  • See data sheet for additional features

Product Details

The AD9559 is a low loop bandwidth clock multiplier that provides jitter cleanup and synchronization for many systems, including synchronous optical networks (SONET/SDH). The AD9559 generates an output clock synchronized to up to four external input references. The digital PLL allows for reduction of input time jitter or phase noise associated with the external references. The digitally controlled loop and holdover circuitry of the AD9559 continuously generates a low jitter output clock even when all reference inputs have failed.

The AD9559 operates over an industrial temperature range of −40°C to +85°C. If a single DPLL version of this part is needed, refer to the AD9557.


  • Network synchronization, including Synchronous Ethernet and OTN mapping/de-mapping
  • Cleanup of reference clock jitter
  • SONET/SDH clocks up to OC-192, including FEC
  • Stratum 3 holdover, jitter cleanup, and phase transient control
  • Wireless base station controllers
  • Cable infrastructure
  • Data communications

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 (1)

Tools & Simulations

IBIS Models

Product Recommendations

AD9559 Companion Parts

Recommended Clock Drivers

Recommended Linear Regulators

  • For ultralow noise, low dropout: ADP150.

Recommended Switching Controller

  • For a dual controller up to 2 x 25A output current: ADP1829.

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.

PCN-PDN Information

Sample & Buy

Sample & Buy functionality exists in desktop site
Check Inventory

The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.

Price Table Help

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.