Laser Transmitter/Reciever

Discussion in 'The Projects Forum' started by Triplell, Dec 8, 2010.

  1. Triplell

    Thread Starter New Member

    Dec 5, 2010
    Our final project for our circuits class is a Laser Diode Transmitter/Reciever.

    We are able to receive the signal, however our preamp and power amp seem to be not working together.

    The photo diode produces a 50mv signal. We send this into a differential amplifier, and are able to boost it to about 3v. These too components work great.

    We are using a push-pull power amp. There is some cross-over distortion, and we have tried using diodes to fix this, however that still doesn't solve the final issue.

    So when we hook it all together, our output of our preamp is no longer 3v, but much less.

    We figure this has something to do with mismatching impedences, but we can not see to fix it no matter we we try. We have added coupling capacitors, changing out design, etc. Nothing seems to work.

    Here is my most recent design. I did away with the Diff amp, and tried using a C-E amp. Still running into the same problem....$+1...765625E-5+1+-1 o+16+64+0+35+0.3125+0.05+2+-1

    Thanks :)
  2. beenthere

    Retired Moderator

    Apr 20, 2004
    An accurate schematic would be much more useful.