Quad Input, 10-Output, Dual DPLL/IEEE 1588, 1 pps Synchronizer and Jitter Cleaner

The AD9545 supports existing and emerging International Telecommunications Union (ITU) standards for the delivery of frequency, phase, and time of day over service provider packet networks, including ITU-G.8262, ITU-T G.812, ITU-T G.813, ITU-T G.823, ITU-T G.824, ITU-T G.825, and ITU-T G.8273.2.

The 10 clock outputs of the AD9545 are synchronized to any one of up to four input references. The digital phase-locked loops (DPLLs) reduce timing jitter associated with the external references. The digitally controlled loop and holdover circuitry continuously generate a low jitter output signal, even when all reference inputs fail.

The AD9545 is available in a 48-lead LFCSP (7 mm × 7 mm) package and operates over the −40°C to +85°C temperature range.

Note that throughout the data sheet, multifunction pins, such as SDO/M5, are referred to either by the entire pin name or by a single function of the pin, for example, M5, when only that function is relevant.

APPLICATIONS

* Global positioning system (GPS), PTP (IEEE 1588), and synchronous Ethernet (SyncE) jitter cleanup and synchronization

* Optical transport networks (OTN), synchronous digital hierarchy (SDH), and macro and small cell base stations

* Small base station clocking, including baseband and radio

* Stratum 2, Stratum 3e, and Stratum 3 holdover, jitter cleanup, and phase transient control

* JESD204B support for analog-to-digital converter (ADC) and digital-to-analog converter (DAC) clocking

* Cable infrastructures

* Carrier Ethernet

* Dual DPLL synchronizes 1 Hz to 750 MHz physical layer clocks, providing frequency translation with jitter cleaning of noisy references

* Complies with ITU-T G.8262 and Telcordia GR-253

* Supports Telcordia GR-1244, ITU-T G.812, ITU-T G.813, ITU-T G.823, ITU-T G.824, ITU-T G.825, and ITU-T G.8273.2

* Continuous frequency monitoring and reference validation for frequency deviation as low as 50 ppb (5 × 10−8)

* Both DPLLs feature a 24-bit fractional divider with 24-bit programmable modulus

* Programmable digital loop filter bandwidth: 10−4Hz to 1850Hz

* 2 independent, programmable auxiliary NCOs (1 Hz to 65,535 Hz, resolution < 1.37 × 10−12 Hz), suitable for IEEE 1588 Version 2 servo feedback in PTP applications

* Automatic and manual holdover and reference switchover, providing zero delay, hitless, or phase buildout operation

* Programmable priority-based reference switching with manual, automatic revertive, and automatic nonrevertive modes supported