Connect with us

Tsop fails on extreme lighting intensities!

Discussion in 'General Electronics Discussion' started by 24Volts, Feb 24, 2013.

Scroll to continue with content
  1. 24Volts


    Mar 21, 2010

    I am using the Tsop4838 ir sensor and I am
    able to sense objects at different distances.

    I then tried to detect those same objects but
    with a flash light directed right on the tsop sensor.

    To my dismay, the sensor completely died off
    producing NO signal at all!!!!

    Is this normal? I thought this part was able to
    distinguish any disturbances such as Dc lighting,
    sunlight ect... from its 38khz signal ???

    Has anyone experienced these disturbances
    with this sensor ?

    PS... For now I have not provided the details
    of the optical signal I am using.... as I was only
    interested to know if I am the only one experiencing
    these issues. However if relevant, I can provide
    all the signal details should we think that this
    sensor really can work under intense lighting conditions
    such as dc lighting or sunlight.

    thanks for all feedback
  2. (*steve*)

    (*steve*) ¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd Moderator

    Jan 21, 2010
    TSOP is also the abbreviation for a type of surface mount package -- so this subject can seem very weird to someone not familiar with the confusingly similarly named range of sensors...

    If you point a flashlight at the sensor (and I'm guessing it had an incandescent bulb, not a LED) then you will saturate the sensor making it very insensitive to the small signal it's looking for.

    These sensors can handle a small amount of ambient light (actually a lot of ambient light, but a small amount of ambient IR).

    The simple answer is to get a LED torch, or stop pointing it at the sensor.
  3. 24Volts


    Mar 21, 2010
    Hi Steve,

    Ooops, I am sorry.... I should of put the whole part number
    for the thread's title.... I will make sure of that next time.

    Well you see, my project may be exposed to direct
    sunlight. So if it's a sunny day, the tsop4838 may require
    to still detect objects even though it is exposed to a huge
    sunbeam !!!

    Thus the reason I was testing it with a flashlight. If it fails
    with a flash light, we can just image how bad it would be
    with the sun!!!!

    Having said this, according to you, should these devices
    be capable of working even in direct sunlight????

    thanks for your reply!
    Last edited: Feb 25, 2013
  4. (*steve*)

    (*steve*) ¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd Moderator

    Jan 21, 2010
    The only way it would be able to operate in direct sunlight is that it is not in sunlight.

    If you can't shield it from *direct* sunlight, you may not have a happy time.
  5. 24Volts


    Mar 21, 2010
    Hi Steve,

    But does this mean that no sensor in this world
    can work under the powerful rays of our sun??

  6. CocaCola


    Apr 7, 2012
    The sun is a LARGE full spectrum light source, it will easily wipe or at least interfere with any low power modulated IR light source... You can even experience this in your house with IR remotes if you have a lot of windows and direct sun light...

    This is also why things like garage door sensors are funneled down a pipe and focused so that they are shielded from ambient light...

    I have one of those IR controlled helicopters (Syma S107) great little flier in the house, but FORGET about it outside during the day it simply will not work... BTW I have flown it just fine at night outside, but it has to be a very calm day...

    End game if you want to use it outside make it very directional and shielded or go to radio frequencies vs light...
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.
Electronics Point Logo
Continue to site
Quote of the day