The MAX3874 is a compact, dual-rate clock and data
recovery with limiting amplifier for OC-48 and OC-48
with FEC SONET/SDH applications. Without using an
external reference clock, the fully integrated phaselocked
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. An additional serial input (SLBI±) is available for
system-loopback diagnostic testing. Alternatively, this
input can be connected to a reference clock to maintain
a valid clock output in the absence of data transitions.
The device also includes a loss-of-lock (LOL-bar) output.
The MAX3874 contains a vertical threshold control to
compensate for optical noise due to EDFAs in DWDM
transmission systems. The recovered data and clock
outputs are CML with on-chip 50Ω back termination on
each line. Its jitter performance exceeds all SONET/SDH specifications. The MAX3874A is the MAX3874
with a voltage-controlled oscillator (VCO) centered at
2.0212GHz.
The MAX3874 operates from a single +3.3V supply and
typically consumes 580mW. It is available in a 5mm x 5mm 32-pin QFN with exposed pad package and operates
over the -40°C to +85°C temperature range.