VITESSE

SEMICONDUCTOR CORPORATION

G52157-0, Rev 3.2

Page 1

05/01/01

© VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012

Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com

Internet: www.vitesse.com

Preliminary Data Sheet

VSC7925

SONET/SDH 2.5Gb/s Laser Diode Driver

Features

Applications

General Description

The VSC7925 is a single 5V supply, 2.5Gb/s laser diode driver with direct access to the laser modulation

and bias FETs. Laser bias and modulation currents are set by external components allowing precision monitor-

ing and setting of the current levels. Data density outputs are provided to allow the user to adjust the laser bias

in unbalanced data applications. Clock and data inputs have nominal 50

Ω termination resistors and high fre-

quency decoupling capacitors.P

VSC7925 Block Diagram

• Rise Times Less Than 100ps

• High Speed Operation (Up to 2.5Gb/s NRZ Data)

• Single-ended Inputs

• Single Supply

• Direct Access to Modulation and Bias FET’s

• Data Density Monitors

• On-Chip Reclocking Register

• 24-Pin Ceramic Package

• SONET/SDH at 622Mb/s, 1.244Gb/s, and

2.488Gb/s

• Full-Speed Fibre Channel (1.062Gb/s)

DIN

NDIN*

10pF

50

Ω

MK

NMK

IBIAS

NIOUT

IOUT

MIP

VIP

VIB

MIB

DQ

CLK

NCLK*

DCC

* Terminated to off-chip capacitor

10pF

50

Ω

**

**

**

**

** On-die components

DCC