1.25 Gbps Clock and Data Recovery IC

ADN2805

Rev. 0

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FEATURES

Locks to 1.25 Gbps NRZ serial data input

Patented clock recovery architecture

No reference clock required

Loss-of-lock indicator

Single-supply operation: 3.3 V

Low power: 390 mW typical

5 mm × 5 mm 32-lead LFCSP, Pb free

APPLICATIONS

GbE line card

GENERAL DESCRIPTION

The ADN2805 provides the receiver functions of quantization

and clock and data recovery for 1.25 Gbps. The ADN2805

automatically locks to all data rates without the need for an

external reference clock or programming. All SONET jitter

requirements are met, including jitter transfer, jitter generation,

and jitter tolerance.

All specifications are specified for −40°C to +85°C ambient

temperature, unless otherwise noted. The ADN2805 is available

in a compact 5 mm × 5 mm 32-lead LFCSP.

FUNCTIONAL BLOCK DIAGRAM

2

LOL

DATAOUTP/

DATAOUTN

ADN2805

CLKOUTP/

CLKOUTN

2

VCC

VEE

CF1

CF2

PIN

NIN

VREF

BUFFER

VCO

PHASE

SHIFTER

PHASE

DETECT

FREQUENCY

DETECT

DATA

RE-TIMING

LOOP

FILTER

LOOP

FILTER

REFCLKP/REFCLKN

(OPTIONAL)

Figure 1.