BS270, is it a logic level MOSFET?

Discussion in 'General Electronics Chat' started by atferrari, Mar 27, 2012.

  1. atferrari

    Thread Starter AAC Fanatic!

    Jan 6, 2004
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    In this site, third paragraph, they said the BS270 is designed for logic level input.

    In the datasheet I could not find anything suggesting that.

    Is it or it isn't?
     
    Last edited: Mar 27, 2012
  2. Wendy

    Moderator

    Mar 24, 2008
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    Here is the Data Sheet...

    http://www.fairchildsemi.com/ds/BS/BS270.pdf

    I think it is, but the data sheet is unusual in that it does not come out and say so directly. Usually this is a selling feature, so I am a bit uncertain.

    One thing though, data sheets are always your friend.
     
  3. ErnieM

    AAC Fanatic!

    Apr 24, 2011
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    The data sheet calls out the Gate Threshold Voltage when VDS = VGS, ID = 250 μA to be a min of 1 volt and a max of 2.5 volts.

    Yes, that makes it a logic level FET.
     
  4. nickelflipper

    Active Member

    Jun 2, 2010
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    The BS270 looks very similar to the 2N7000 datasheet, only better power handling characteristics, definitely logic level. Also, the pinout is reversed from the 2N7000.
     
  5. jwilk13

    Member

    Jun 15, 2011
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    It is logic level, but I'll ask everyone else this just for the OP's reference:

    Should he be concerned that Rds(on) is not specified for any Vgs below 4.5V (if he were considering using 3.3V to turn it on)?
     
  6. crutschow

    Expert

    Mar 14, 2008
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    From the data sheet I would say it works ok for 5V logic but not for 3.3V logic, which is barely above the threshold voltage.
     
  7. Audioguru

    New Member

    Dec 20, 2007
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    When its gate-source voltage is logic-level at 4.5V:
    1) Its maximum on-resistance is 3 ohms.
    2) Its drain-source voltage drop is 2V when its current is at least 400mA.

    Is that good enough for your circuit?
     
  8. atferrari

    Thread Starter AAC Fanatic!

    Jan 6, 2004
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    I have no circuit in mind AG.

    I realize that maybe, in 1995 there were not so many logic level MOSFETS, at least described as such...

    Thanks to all replying.
     
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