BCM8211

Features:

* 2.488-Gbps SONET/SDH transceiver with dual differential serial I/O
* Fully integrated CDR, MUX, DEMUX, and CMU
* Selectable LVPECL/CMOS 16-bit, 155.52-Mbps interface t framer or network processor
* On-chip PLL-based clock generator
* Line and system loopback modes
* Loss-of-signal output (LOSB) and input (LOSIB)
* TX and RX lock detect
* Elastic buffering with FIFO overflow alarm
* Selectable 77.76/155.52-MHz reference clock
* Selectable RX clock and RX data squelch on LOS
* Selectable loop timing mode
* Single 2.5V or dual 2.5V/3.3V supplies
* Power dissipation: 1.2W typical
* 14 20 mm, 128-pin PQFP package
* Standard CMOS fabrication process




Application

* OC-48/STM-16 transmission equipme
* SONET/SDH optical modules
* ADD/DROP multiplexers
* Digital cross-connects
* ATM switch backbone
* SONET/SDH test equipment
* Terabit and edge routers




Description

The BCM8211 SONET/SDH transceiver is a fully integrated serialization/deserialization SONET OC-48 (2.488 Gbps) interface device with an integrated Clock Multiplication Unit (CMU) and an integrated Clock and Data Recovery (CDR) circuit. On-chip clock synthesis is performed by the high frequency, low jitter, phase locked loop on the BCM8211 transceiver, allowing the use of a slower  of BCM8211 77.76/155.52 MHz external transmit clock reference.

Dual Rx and Tx 2.488-Gbps interfaces support dual-fiber ring architectures. The selected interface of BCM8211 is active while the unselected interface remains in powered-down state. Clock recovery is performed on the device by synchronizing its on-chip VCO directly to the incoming data stream.