Connect with us


Discussion in 'Hobby Electronics' started by Zman, Dec 21, 2004.

Scroll to continue with content
  1. Zman

    Zman Guest

    Hey there

    when placed in the sun, a small led gives off a reading on my voltmeter,
    goes up and down. The only thing is, how do i know what reverse
    current/voltage im going to get just by looking at the information? is there
    a formula to use and does mCd make a diff in voltage or current when giving
    power out?

    the specs are

    15VDC 5mm LED
    (all typical values)
    luminous intensity 120
    Peak emission wavelength 573
    spectral half width 15
    flash rate (freq) 2.4
    operating voltage 5
    forward voltage 5
    reverse voltage .04

    thank you
  2. Eddie

    Eddie Guest

    strange led spec, but yes, not many people know that a led will generate a
    small voltage and bugger-all current when exposed to light
  3. Didn't you like the fairly comprehensive replies before ??
    Why use a flashing LED for this purpose ??
    Particularly against expert advice ??
  4. MC

    MC Guest

    Actually *all* semiconductors will produce some voltage and current
    if given enough radiation.
    One reason why most semiconductors are enclosed in optically-opaque
    packaging is to try and reduce optical side-effects.

    Unless the device has been specifically designed for power generation
    (ie. a solar cell), then you'll find that the enery-conversion
    efficiency is rather low and the output will depend a lot on what the
    semiconductor material actually is.
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Similar Threads
  1. LED

  2. LED

  3. LED

  4. LED

  5. led

  6. Led

  7. LED

  8. LED

Electronics Point Logo
Continue to site
Quote of the day