LED/Laser Diode Characterization System

  1. LED/Laser Diode Characterization System
    1. Team Members
    2. Project Overview
    3. Minimum Requirements
    4. Submitted Documents
    5. Site Map
    6. Useful Links
    7. Recent Changes
      1. References

Team Members

Undergraduates
David Overgaard overgaad@onid.orst.edu
Pat Bice bicep@onid.orst.edu
Steven Braun braunst@onid.orst.edu

Mentor
Tom Plant tkp@eecs.oregonstate.edu

Sponsor
ON Semiconductor

Project Overview

The goal of this project is to create an easy-to-use curve tracer for Oregon State University’s optics laboratory. The device will be reliable, safe (to the user and the device under test), and output the diode characteristics to a graphical interface.

Currently the optics labratory is analyzing device characteristics such as polarity and current vs. voltage (I-V) curves of diodes through the use of an antiquated curve tracer. The current curve tracer is tube driven and lacks the ability to store measured data. Tubes are currently worn to the point of producing inaccurate results. Since tubes are expensive, and this device is used frequently, a more robust and reliable design is required.

Our solution is to incorporate a micro-controller and computer interface to allow for a reliable portable device. Utilizing Op Amps as a current source instead of the bulky tubes will help reduce cost and size. The new curve tracer will feature automated as well as manual measuring of I-V and light intensity vs. current (L-I) curves. By designing an easy to use, compact, and accurate curve tracing device we will allow characterizing of LEDs and LDs to be simpler for the user.

Building off of the principles of laser diodes we've chosen to also design a free space communication device as an optional project if time and funding permits. By understanding the characteristics of laser diodes we will modulate a laser diode to transmit an audio signal across a distance of at least 30 feet. A device that can achieve short range communications can be beneficial in home and commercial use in place of running a copper conductor.

Minimum Requirements

  • Able to measure and output an accurate I-V curve for LEDs and LDs.
  • Able to carry out all functions regarding LED and LD testing without damage to LED/LD.
  • Able to determine correct polarity of LEDs or LDs.
  • Able to measure and output an optical power vs. forward current (L-I) curve for LEDs and LDs.
  • Provide an easy-to-use user interface.
  • Ability for manual measurement.
  • Ability for automatic measurement.
  • (Optional) Design and build a small, laser diode optical communication source to transmit MP3 audio files.

Submitted Documents

Submitted Documents

Site Map

1 Project Overview
2 Needs Identification and Background Research
3 System Requirements and Desired Features
4 Design Solutions
5 Top Level Block Design

5.1 Micro-Controller
5.2 Manual Control (On Board)
5.3 Currect Source
5.4 Protect
5.5 Diode Connect
5.6 Photo-Detector
5.7 Chassis
5.8 LCD Display
5.9 Voltage Regulator

6 Testing

6.1 Testing Evidence

7 Project Timeline
8 Budget
9 Expo Materials
10 SVN?

ECE 44X - Senior Design 2009-10 Main Page
Oregon State University
Wiki Formatting

Recent Changes

11/05/10

05/18/10

05/12/10

05/10/10

References


Attachments