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[drip sensor] which photodiode with an infrared LED ?

Discussion in 'Electronic Projects Design/Ideas/Reviews' started by loup-garou, May 8, 2009.

  1. loup-garou

    loup-garou New Member

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    [drip sensor] how to identify a photodiode ?

    Everybody Hi,

    I have to make the following drip sensor (see attached file), the caracteristics of the sensor Assembly (infrard LED+ photodiode) used in the file aren't unfortunately mentionned and recently I got a senor assembly (an MLED930 and a photodiode that were in use together in another drip sensor (analog one), my problem is that a part of name of the photodiode was erased,the only thing I know about it is that it began with BP (it has this shape : http://sjostromaudio.com/hifi_pics/hifi_100pr/photodiode.jpg) . thus, so I'm not able to adapt it to the schematic (page 2/fig.3 of the second attached file).

    what should I do, how to test it in order to identify it (resistances to use ,polarization ) ?

    Any help will be will be hugely appreciated .
     

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    Last edited: May 8, 2009
  2. loup-garou

    loup-garou New Member

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    @Moderator : could you please change the title of the topic to "[drip sensor] how to identify a photodiode ?", thanks.
     
    Last edited: May 8, 2009
  3. loup-garou

    loup-garou New Member

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    Hi,

    any suggestion ?
     
    Last edited: May 9, 2009
  4. dave

    Dave New Member

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  5. Sceadwian

    Sceadwian Banned

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    Well it's a diode so you should be able to use a multi-meter in diode test mode to determine the anode/cathode. Not sure hot to determine what resistor you should use.
     
    Last edited: May 9, 2009
  6. loup-garou

    loup-garou New Member

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    Hi Sceadwian,

    thank you, you're right for the cathode/anode fixing. another thing, the photodiode used in the attached file is reverse polarized while I don't know whether my photodiode should be polarized that way or not.
     
  7. Sceadwian

    Sceadwian Banned

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    It should go in the same direction as the one from the existing circuit.
     
  8. loup-garou

    loup-garou New Member

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    I think so.
     

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