© VITESSE SEMICONDUCTOR CORPORATION

Page 1

11/9/99

741 Calle Plano, Camarillo, CA 93012 • 805/388-3700 • FAX: 805/987-5896

VITESSE

SEMICONDUCTOR CORPORATION

Preliminary Datasheet

VSC8166

2.488 Gbit/sec

1:16 SONET/SDH Demux with Clock Recovery

G52252-0, Rev. 3.0

Features

General Description

The VSC8166 demultiplexes a 2.488Gbp/s LVPECL serial input datastream (DI+) to 16-bit wide, LVPECL

155Mb/s parallel data outputs (D0:D15+) for SONET/SDH applications. It has an integrated clock and data

recovery unit with an on-chip PLL that internally generates a 2.488GHz clock in phase with the incoming data.

Internal divider circuits are used to take the high-speed clock and generate 155.52MHz (CLK16O+) and

77.76MHz (CLK32O+) LVPECL external output clocks. The incoming data is retimed and demultiplexed to a

16-bit word which is clocked out of the demultiplexer by the 155.52MHz output clock.

Alarm functions support typical telecom system applications. A TTL Loss Of Lock (LOL) indicator can be

externally enabled (LOLEN) to detect when the device goes out of lock, which would most often occur in the

event of a loss of valid data. A TTL No-Reference (NOREF) output indicator flags when the LVPECL Clock

Reference (REFCLK) input to the VSC8166 either is removed, or goes severely out of tolerance. For Loss Of

Signal (LOS) conditions from an Optics Module, the VSC8166 provides a polarity (POL) input to accommo-

date any polarity differences.

Only a single 3.3V power supply is required for device operation and the device is packaged in a thermally

enhanced 128 Pin 14x20x2 mm PQFP Package.

VSC8166 Block DIagram

• 2.488Gb/s 1:16 Demultiplexer

• Fully Integrated Clock and Data Recovery

• Single 3.3V Supply Operation

• Differential LVPECL Low Speed Interface

• Maintains Clock Output in the Absence of

Data

• Loss of Lock, Loss of Signal Indicators

• 128 Pin 14x20x2 mm Enhanced PQFP Pkg.

• 2.3W Max Power Dissipation

Clock

Recovery

Data

Divide

by 16

Divide

by 2

D0+

D0-

D15+

D15-

CLK16O+

CLK16O-

CLK32O+

CLK32O-

DI+

DI-

REFCLK+

REFCLK-

Re-time

NOREF

LOS

LOLEN

LOL

POL

1

0