© VITESSE SEMICONDUCTOR CORPORATION

Page 1

8/28/00

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

VITESSE

SEMICONDUCTOR CORPORATION

Advance Product Information

VSC7146

2.5Gb/s, 20-Bit Transceiver

G52162-0, Rev. 2.7

Features

General Description

The VSC7146 is a 2.5Gb/s Transceiver optimized for ease-of-use and efficiency in high-performance data

transmission systems. The VSC7146 accepts two 10-bit 8b/10b encoded transmit characters, latches them on

the rising edge of Transmit Byte Clock (TBC) and serializes the data onto the TX+/- differential outputs at a

baud rate, which is 20 times the TBC frequency. The VSC7146 also samples serial receive data on the RX+/-

differential inputs, recovers the clock and data, deserializes it onto two 10-bit receive characters, outputs a

recovered clocks at one-twentieth of the incoming baud rate and detects Fibre Channel “comma” characters.

The VSC7146 contains on-chip Phase-Lock Loop (PLL) circuitry for synthesis of the baud-rate transmit clock,

and extraction of the clock from the received serial stream. These circuits are fully monolithic and require no

external components.

Block Diagram

• Speed Selectable Full-Duplex Transceiver:

- 1.06/2.12Gb/s for FibreChannel

- 1.25/2.5Gb/s for Gigabit Ethernet

• 20-Bit TTL Interface for Transmit and

Receive Data at 125MHz

• Monolithic Clock Synthesis and Clock

Recovery - No External Components

• 125MHz TTL Reference Clock

• Automatic Lock-to-Reference Function

• Suitable for Both Coaxial and Optical Link Appli-

cations

• Low Power Operation: 2.5 W max

• 80-Pin, 14mm Thermally-Enhanced EDQUAD

Package

• Single +3.3V Supply

RX+

RX-

Q D

Serial to

Parallel

Clock

Recovery

Retimed

Data

Recovered

Comma

Detect

Q D

R0:19

Frame

Logic

COM_DET

EN_CDET

T0:19

PLL Clock

Multiply (x20)

Parallel

to Serial

Serial Data

Clock

Synthesized

Clock

D Q

TX+

TX-

EWRAP

÷ 20

RBC

20

20

TBC

2:1

125 MHz

125 MHz

2.5 Gb/s

2.5 Gb/s

2.5 GHz

REF

TXRATE

RBCN

RXRATE

BCMN

D Q