Connect with us

H-bridge using only n-channel mosfets

Discussion in 'General Electronics Discussion' started by stube40, Aug 26, 2010.

Scroll to continue with content
  1. stube40

    stube40

    85
    0
    Feb 9, 2010
    I have created an H-bridge PC with 4x floating gate drivers and 4x IGBTs (see attached schematic showing half of h-bridge).

    It works very nicely but I would like to replace the IGBTs with n-channel MOSFETs. However, all the H-bridge designs I've seen use n-channels on the low side and p-channels on the high side.

    Since my design uses independant galvanically isolated DC-DC converters which effectively provide each of the 4x gate drivers with their own floating supply, is it possible that I can just do a simple straight swap between of the IGBTs with N-channel mosfets?
     

    Attached Files:

  2. Militoy

    Militoy

    180
    0
    Aug 24, 2010
    I don’t see any problem using N-channel FETs instead of your IGBTs – virtually all of our SMPS bridges and half-bridges use N-FETs both top and bottom. I did notice that you have made no provision for a separate turn-off path to dump gate capacitance – so I assume your gate resistors are fairly low in value, and you’re taking other measures to prevent cross-conduction. We also typically put around 10K from gate to source, to prevent the gate from floating, when not being actively held off.
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-