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Small size diode needed

  1. Oct 2, 2009 #1
    guys I'm looking for general purpose diode like 1N4148.
    it should be small.(smaller than 1n4148).
    surface mount solution is not going to work as they are very expensive.

    I'm working on a circuit and need to use parts small as possible. i use 1/8w resistors and 1n4148 as diodes as they are small.

    can you suggest me any diode that has smaller size than 1N4148?

    current ratings are not a problem.

  2. jcsd
  3. Oct 2, 2009 #2


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    Gold Member

    1N4148 is about as small as they get in leaded parts. Can you stand them on end to reduce the footprint?
  4. Oct 2, 2009 #3
    I'm voryning about 3D space so standing them wont help
  5. Oct 2, 2009 #4


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    You can get surface mount parts quite cheaply although you may have to buy 10 or so at a time:

    This site lists them at AU$3.35 for a pack of 10 or US$0.28 each.

    Doesn't seem too bad.

    But the 1N4148 is already a very small diode even with wire leads on it.
  6. Oct 3, 2009 #5
    well in here normal one 1N4148 cost $ 0.01 and surface mount one cost $0.15
    in above link its cost about $3.15 per one
  7. Oct 3, 2009 #6
    guys BAW56 is common anode diode array (of two diodes) is there any common cathode ones?
  8. Oct 3, 2009 #7


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    Staff: Mentor

    BAV-99s are the traditional SMT substitutes for 1N4148s.
  9. Oct 3, 2009 #8


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    In the link, the price was AU$3.35 for a pack of 10, or US 28 cents each.

    1N4148WS Diode SMD SOD-323 PK10

    but if you can get them for 15 cents, are you saying that is too expensive?
  10. Oct 19, 2009 #9
    The standard most used package is SOT-23, for diodes, dual diodes, transistors and many other components. For single diodes, 2 of the 3 leads are used: the one on one side and one of the 2 on the other.

    There are versions smaller than SOT-23, but not likely you need that. Smaller is harder to solder. Many catalogs like Digikey will shoe the dimensions, and ordering info. Catalog, pages available online. The diode you asked about is in it, and cheap.
  11. Oct 19, 2009 #10
    thanks :smile:
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