Low Side MOSFET Driver IC

Discussion in 'The Projects Forum' started by mvandrunen, May 21, 2008.

  1. mvandrunen

    Thread Starter New Member

    May 21, 2008
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    I have a project to drive two power mosfets which sink 130VD @ 2.5 A each. Both will be driven out of phase with eachother. I was thinking about using a IR4427 dual low side gate driver IC with two IRFP4242 Power Mosfets.

    Is all I need from the output of the gate driver one gate resistor in series with the Mosfet gate? The source of the Mosfet is tied to ground with the drain to a transformer winding whichis connected to the 130 VDC rail.

    I am switching each input of the driver with a TTL square wave at 40khz. Each input in opposite phase with eachother.
     
  2. Audioguru

    New Member

    Dec 20, 2007
    9,411
    896
    The IR4427 has Cmos inputs. Their logic voltage thresholds are almost but not the same as old TTL voltage thresholds. The minimum input high voltage is 2.7V. Some TTL ICs have an output high voltage of only 2.4V.
    Use a 10 ohm resistor in series with each gate mounted close to the gate to prevent the Mosfets from oscillating at a very high frequency.
     
  3. mvandrunen

    Thread Starter New Member

    May 21, 2008
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    Is there an easy way to pull the voltage up to 2.7V? Is it better to change the flip flop circuit to a CMOS compatable device?

    Also, how did you calculate te gate resistor and wattage?
     
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