mosfet compatibility

Discussion in 'The Projects Forum' started by brad20, Feb 27, 2014.

  1. brad20

    Thread Starter New Member

    Apr 7, 2013
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    0
    Can you mix 200v 50a with 200v 69a, 250v 62a rated nch mosfets in a power inverter's output section either modified or pure sine?
     
  2. wayneh

    Expert

    Sep 9, 2010
    12,145
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    Each MOSFET needs to meet (and exceed) the minimum specs needed for its application. A MOSFET will work fine under milder conditions as long as it is not damaged by excessive voltage or current. So if it's rated to 200V but only sees 50V, that is no problem.

    So without more information, the short answer is yes, mixing is not per se a problem.
     
  3. bertus

    Administrator

    Apr 5, 2008
    15,648
    2,347
    Hello,

    There are more specifications needed to select a mosfet.
    You have the Rds, the Vgs (gate threshold), the gate capacitance that can be different for the mosfets.

    Bertus
     
  4. wayneh

    Expert

    Sep 9, 2010
    12,145
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    Agreed. I didn't mean to imply my example specifications were the only ones you need to look at. We just cannot tell what's important without a lot more detail.
     
  5. brad20

    Thread Starter New Member

    Apr 7, 2013
    12
    0
    The output section is using a 250v capacitor. Would that mean It would have to be a 250v mosfet or could it use a 200v rated mosfet FDA70n20 or fdL100n50 orig mosfets used are irfp264n 250v 44a mosfet.
     
    Last edited: Mar 22, 2014
  6. brad20

    Thread Starter New Member

    Apr 7, 2013
    12
    0
    The output section is using a 250v capacitor. Would that mean It would have to be a 250v mosfet or could it use a 200v rated mosfet FDA70n20 or fdL100n50 orig mosfets used are irfp264n 250v 44a mosfet.

    irfb264n
    250V
    Current - Continuous Drain (Id) @ 25°C 44A (Tc)
    Rds On (Max) @ Id, Vgs 60 mOhm @ 25A, 10V
    Vgs(th) (Max) @ Id 4V @ 250µA
    Gate Charge (Qg) @ Vgs 210nC @ 10V
    Input Capacitance (Ciss) @ Vds 3860pF @ 25V
    Power - Max 380W
    200V

    fda70n20
    200v
    Current - Continuous Drain (Id) @ 25°C 70A (Tc)
    Rds On (Max) @ Id, Vgs 35 mOhm @ 35A, 10V
    Vgs(th) (Max) @ Id 5V @ 250µA
    Gate Charge (Qg) @ Vgs 86nC @ 10V
    Input Capacitance (Ciss) @ Vds 3970pF @ 25V
    Power - Max 417W

    100n50
    500V
    Current - Continuous Drain (Id) @ 25°C 100A (Tc)
    Rds On (Max) @ Id, Vgs 55 mOhm @ 50A, 10V
    Vgs(th) (Max) @ Id 5V @ 250µA
    Gate Charge (Qg) @ Vgs 238nC @ 10V
    Input Capacitance (Ciss) @ Vds 12000pF @ 25V
    Power - Max 2500W
     
  7. wayneh

    Expert

    Sep 9, 2010
    12,145
    3,055
    It's impossible to know for sure without more information. But to be safe without that information, anything less than 250V becomes a risk.
     
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