VITESSE

SEMICONDUCTOR CORPORATION

Advance Product Information

VSC7809

Photodetector/Transimpedance Amplifier

Family for Optical Communication

G52195-0, Rev 2.4

Page 1

04/05/01

© 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

General Description

The VSC7809 integrated Photodetector/Transimpedance Amplifier provides a highly integrated solution

for converting light from a fiber optic communications channel into a differential output voltage. The benefits

of Vitesse Semiconductor’s Gallium Arsenide H-GaAs process are fully utilized to provide very high bandwidth

and low noise in a product with a large optically active area for easy alignment. The sensitivity, duty cycle dis-

tortion and jitter meet or exceed all Fibre Channel and Gigabit Ethernet application requirements. Parts are

available in either die form, flat-windowed packages or in ball-lens packages.

By using a metal-semiconductor-metal (MSM) photodetector with a monolithic integrated transimpedance

amplifier, the input capacitance is lowered which allows for a larger optically active area than in discrete photo-

detectors. Integration also allows superior tracking over process, temperature and voltage between the photode-

tector and the amplifier, resulting in higher performance. This part can easily be used in developing Fibre

Channel Electro-Optic Receivers which exhibit very high performance and ease of use.

VSC7809 Block Diagram

Part Number

Data Rate

Bandwidth

(MHz)

Input Noise

(

µW rms)

Optically Active Area

(

µm diameter)

VSC7809

1.25Gb/s

800

1.4

100

• Integrated Photodetector/Transimpedance

Amplifier Optimized for High-Speed Optical

Communications Applications

• Fibre Channel/Gigabit Ethernet Compatible

• High Bandwidth

• Low Input Noise Equivalent Power

• Large Optically Active Area

• Single 3.3V Power Supply

Both DOUTP and DOUTN are back-terminated to 25

Ω.

Photodetector/Transimpedance Amplifier

DOUTP

DOUTN

+3.3V

GND