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General Description

The MAX3873A is a compact, low-power 2.488Gbps/2.67Gbps clock-recovery and data-retiming IC for SDH/SONET applications. The phase-locked loop (PLL) recovers a synchronous clock signal from the serial NRZ data input. The input data is then retimed by this recovered clock, providing a clean data output. The MAX3873A meets all SDH/SONET jitter specifications, does not require an external reference clock to aid in frequency acquisition, and provides excellent tolerance to both deterministic and sinusoidal jitter. The MAX3873A provides a PLL loss-of-lock (LOL) output to indicate whether the CDR is in lock. The recovered data and clock outputs are CML with on-chip 50¦¸ back terminations on each line. The clock output can be powered down if not used.

Features

? Fully Integrated Clock Recovery and Data Retiming

? Power Dissipation: 260mW with +3.3V Supply

? Clock Jitter Generation: 5mUIRMS

? Exceeds ANSI, ITU, and Bellcore SDH/SONET Jitter Specifications

? Differential Input Range: 50mVP-P to 1.6VP-P

? Single +3.3V Power Supply

? PLL Fast Track (FASTRACK) Mode Available

? Clock Output Can Be Disabled

? Input Data Rate: 2.488Gbps or 2.67Gbps

? Selectable Output Amplitude

? Tolerates 2000 Consecutive Identical Digits

? Loss-of-Lock Indicator

? Differential CML Data and Clock Outputs

? Operating Temperature Range: -40¡ãC to +85¡ãC

Applications

??? Switch Matrix Backplanes

??? SDH/SONET Receivers and Regenerators

??? Add/Drop Multiplexers

??? Digital Cross-Connects

??? SDH/SONET Test Equipment

??? DWDM Transmission Systems