VITESSE

SEMICONDUCTOR CORPORATION

Advance Product Information

VSC7969

3.125Gb/s Integrated Transimpedance

and Limiting Amplifier with Signal Detect

G52355-0, Rev 2.0

Page 1

02/09/01

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

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

Internet: www.vitesse.com

Features

Applications

General Description

The VSC7969 is a 3.125Gb/s transimpedance amplifier IC with a built-in limiting amplifier, a signal detect

feature and a photocurrent monitor. The VSC7969 does not require any external electrical components in the

construction of a high performance optical receiver such as for SONET/SDH applications. The analog output is

a differential signal with a minimum amplitude of 200mVp-p (single-ended). The VSC7969 operates with a sin-

gle power supply with a maximum power dissipation of 300mW. A PIN photodiode or APD can be connected

and separately biased to provide optimal performance.

The VSC7969 provides filtered bias for MSM and PIN photodetectors; applications using an APD photode-

tector must supply bias separately. The VSC7969 also provides a photocurrent monitor whose output is linearly

proportional to the input photocurrent.

The VSC7969 can operate from a single +3.3V supply or a +5V or -5.2V supply. The VSC7969 is offered

in die form and in a 16-pin plastic thin-shrink small outline package (TSSOP-16). A fully tested TO-46 outline

packaged receiver with a photodetector is also available.

Block Diagram

• Integrated TIA and Limiting Amplifier

• Low Power Consumption for SFF Applications

• TO Package-Compatible Layout

• On-Chip Signal Detect

• On-Chip Linear Photocurrent Monitor

• Single 3.3V Supply

• 5V Supply Operation via Wirebond Option

• Compatible with PIN or Avalanche Detectors

• Packages: 16-Pin TSSOP, TO-46, Bare Die

50

Ω

Regulator

VSC7969

+3.3V

0.1µF

VOUTP

VCCD

Outputs need to

be AC-coupled

Dual power supply pins are

provided for +5V or +3.3V

operation. Only one power

supply pin should be connected.

VCCS

VOUTN

SD_OUT

SD_ADJ

IMON

0.1µF

+3.3V

+5V

50

Ω

Signal

Detect

Monitor

Filter

In

GND

• 2.488Gb/s, 3.125Gb/s SONET OC-48/

SDH STM-16

• 2.125Gb/s Fibre Channel

• 2.5Gb/s or 3.125Gb/s Ethernet Applications with

8B/10B Overhead

• SFF Transceivers