Gigabit Ethernet – IEEE 802.3z
The Choice of a New Generation
Design Presentation
ECE 4006c
G2- Gigabit Ethernet Intel/Agilent TX
Javier Alvarez, gte006r
Astou Thiongane, gt3083a
Ebrima Kujabi, gte212s
Objectives

General Use
– MAXIM 3287 Kit

Board Specs
– Basic Features
– Component Analysis
– Safety Features
– Issues with Laser Mounting

Testing Procedures
 Design Board
General Use of MAXIM board

Remove transceiver Module
from Intel PRO/1000 Board.
 Replace transmitter with
MAXIM 3287
– Optical Transmitter Module
Board Specs

Basic Features
– Optimized operation at 1.25 Gbps.
– Supports a current modulation up to 30mA.
– Deterministic Jitter of approx. 22 ps.
– Requires a 3.3 V to 5V power supply.
Component Analysis

Differential Input & Output
– Eliminates noise in channel

Reference Voltage
– Used for programming a laser
bias current in VCSEL
applications (~0.8mA)

Monitor Diode
– Monitors Laser Current
– Not supported by board
Component Analysis (Cont’d)

Current Modulation
Control (Pin 15)
 Temperature Coefficient
Control (Pin 16)
Laser Mounting

VCSEL Mounting
– Common-Cathode
Configuration

Avoiding Laser Ringing
or Overshooting
– Reduce Length of Leads
– Typical Package Leads
have inductances of
25nH/in.
Common-Cathode Configuration
Safety Features

Shutdown Driver Output (SHDNDRV)
 Power-On Reset (POR)
– Resets Laser when turned off.
– Rejects Noise caused by VCC during power-on or hot
plugging.

Bias Controlling Transistor Driver (BIASDRV)
– Transistor placed between BIASDRV and VCC
– Ensures Low Noise Operation
– Rejects Power Supply Noise

Decoupling Capacitors at VCC & GND
Testing Procedures

The Eye Mask from
IEEE 802.3z
– Distinction between
logical 1 and 0
– Allows to see amount
of jitter

Bit Error Testing
– Tektronic BERT

Testbed
Board Design

Parts List Consists:
– VCSEL (~850 nm)
– SMA Connectors
– SMA Cable
– Resistors
– Capacitors
– Inductors
– 3 to 5 Volt Power
Supply
Picture provided by: http://www.ece.gatech.edu/academic/courses/fall2001/ece4006/1G2/