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[Help]Make Mosfet driver..

Discussion in 'Members Lounge' started by Silent_Sense, Mar 21, 2009.

  1. Silent_Sense

    Silent_Sense New Member

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    This is my first posting here..
    I`m new in here n very newbie if talking about electronic technology.
    I need your help:confused:
    I study in Electro Faculty, I choose it, because i`m very interesting with robot,etc. But, i don`t have a basic about it.
    I have homework to make simple "driver Mosfet"..
    Can you help me to give information about it..
    How to Make?Design?
    This is very usefull for me..
    Sory, if my english is bad hehe..
    Thank before..
     
    Last edited: Mar 21, 2009
  2. tcmtech

    tcmtech Well-Known Member Most Helpful Member

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    Are you trying to drive a mosfet. or are you trying to drive something with a mosfet?
     
  3. forumlicker007

    forumlicker007 New Member

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    silent sense, this make sense for me that ou are not a newb but an exellent member.tel me who r u. hehe..
    atleast u dont have keeboard problem.
    007:D
     
  4. dave

    Dave New Member

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  5. tcmtech

    tcmtech Well-Known Member Most Helpful Member

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    Did I have a stroke in my language center of my brain?
    The wording and spelling seems all F-ed up today.
     
  6. Silent_Sense

    Silent_Sense New Member

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    Trying to drive a mosfet ^^ with the gate. when i learn n ask someone about it, they said "it`s very simple". But he didn`t want give me clue or something to help me, just praise himself =_=.

    Hehe..Excllent??Thx..I just want to learn more more n more..
    I`m from Indonesia
    My Name is Matias..
    Nice to know all of you..

    F-ed??what it means?
     
    Last edited: Mar 23, 2009
  7. dknguyen

    dknguyen Well-Known Member

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    It is easiest to use a gate-driver IC.

    Are you trying to drive a low-side MOSFET? Or a high-side MOSFET?
     
  8. audioguru

    audioguru Well-Known Member Most Helpful Member

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    We don't talk about the birds and the bees here.
    (Yesterday I saw some swans doing it.) Hee, hee.
     
  9. Sceadwian

    Sceadwian Banned

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    Ran into four ducks at the local supermarket, I thought they were huddling for warmth. Apparently it was three Males and a Female. They weren't huddling for warmth =O
     
  10. Silent_Sense

    Silent_Sense New Member

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    Waw..=_=
    Back to Topic hehe..

    Low side Mosfet..any solution?
    Can u give me some pic?
     
  11. dknguyen

    dknguyen Well-Known Member

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    Well, you can just use a gate driver IC. THat's the simplest and most compact solution. Or you can build one discretely.

    THe simplest discrete solution is a high-side NPN BJT and a low-side PNP transistor (yes, that's right the NPN Is on the high-side and the PNP is on the low-side. This means that the transistor gradually turns off as the power MOSFET gate capacitance becomes charged and helps to prevent shoot-through currents in the gate driver).
    [​IMG]

    A more advanced solution is to use BJTs and MOSFETs in parallel:
    [​IMG]
    In this example they use two NPN BJTs, but you could instead replace that with a high-side NPN and low-side PNP just like the previous example (and you can remove the inverters as well if you do that).

    The BJTs turn on very quickly and provide the high current pulse needed to charge or discharge the power MOSFET gate capacitance. But they can't bring the capacitance close to the rails of the gate drive supply voltage. THe MOSFETs turn on slower but can pull the gate capacitance very close to the rail voltage.
     

    Attached Files:

    Last edited: Mar 23, 2009
  12. Silent_Sense

    Silent_Sense New Member

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    Thank You..
    will be very usefull for me...:D
     

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