Testing TSOP1738

Discussion in 'The Projects Forum' started by jj_alukkas, Jun 15, 2011.

  1. jj_alukkas

    Thread Starter Well-Known Member

    Jan 8, 2009
    751
    5
    Hello,

    I have 2 Tsop1738 IR receivers which when used in a usb player ckt, both doesnt seem to respond. So I would like to know if there is any simple way to test them ? I tried giving 3.6v to the vs and grounded pin 1 and tested for a voltage on the output pin, but it always shows a constant voltage whether I use a remote or not. Both are showing the same response. Can I conclude that the TSOP's as blown?

    Sorry for making this new thread as there was an existing thread on this forum, but it was stated as a member that he had responded to the thread starter on another forum.
     
  2. bertus

    Administrator

    Apr 5, 2008
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  3. jj_alukkas

    Thread Starter Well-Known Member

    Jan 8, 2009
    751
    5
    Thank you for that page :) After I tried running the IR chip at 5.1V, I still didnt get the tsop working on the usb board ckt or led ckt, but the voltmeter shows a rise of 0.01v from say 3.30 to 3.31v on the Vout when I press buttons on the remote. I guess thats not good as it should stay low and when i press a button it should go high by atleast a volt or 2 ?

    when I gave 3.6v a supply previously, there was no difference at all. So what should I conclude?
     
  4. RRITESH KAKKAR

    Senior Member

    Jun 29, 2010
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    Yeah, Bertus SIR is right.........
     
  5. bertus

    Administrator

    Apr 5, 2008
    15,646
    2,344
    Hello,

    The TSOP1738 needs a modulated 38 kHz signal that is pulsed.
    If the signal is not pulsed the AGC will reduce the signal and the sensitivity will fall dramaticaly.

    Here are some pages from the EDUCYPEDIA with IR remote control information:
    Infra Red Circuits
    RC5 code

    Bertus
     
  6. jj_alukkas

    Thread Starter Well-Known Member

    Jan 8, 2009
    751
    5
    Yes, I was using the remote which came with the usb board. But, good news, one of the two tsop's i had were blown. on testing the second, I got a good 5v as high on the vout and when i press a button, i get a drop of 0.5 volts!! so I wired it onto the usb board with a seperate 5v line for the tsop and guess what it worked!! I still wonder why the board only has a 3.3v line for vd for TSOP to run ???

    Anyway Thanks a lot Bertus!! My problem is solved!
     
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