Driving an IGBT using a microcontroller

Discussion in 'General Electronics Chat' started by stube40, Feb 18, 2010.

  1. stube40

    Thread Starter Member

    Feb 3, 2010
    Anyone have any suggestions how to drive an IGBT via a microcontroller? I'm trying to drive a STGE200NB60S with an Atmel AVR CPU.

    The AVR can run at both 3.3V and 5V and the gate threshold of the IGBT is 3V, so in theory I could just connect up an go. But, i cant help thinking that it can't be that simple, can it?

    Also, if anyone has any suggestions where I can source low numbers (<= 5) of the 64-lead TQFP version of the AVR (id AT90CAN128-16AU or AT90CAN128-16AI) then I'd love to hear them - Digikey dont do the TQFP package.
  2. S_lannan

    Active Member

    Jun 20, 2007
    How fast do you want to switch the IGBT?
  3. beenthere

    Retired Moderator

    Apr 20, 2004
    You might want to look more closely at the data sheet. The device is rated for low frequency operation, largely because of the enormous gate capacitance.

    The threshold voltage is the point at which the device begins to conduct. If you want the critter to switch with few losses, arrange for the gate to go 15 volts above the source, as suggested in the data sheet. It will only be partly on at 5 volts, and will probably get very hot if you are trying to run anything like 100 amps through it.

    You will need a pretty good source to push charge on and pull it off that IGBT gate.
  4. jpanhalt

    AAC Fanatic!

    Jan 18, 2008
  5. stube40

    Thread Starter Member

    Feb 3, 2010
    Thanks for the replies - I need 4 of these IGBTs to switch a 150V / 40A DC power source in a H-bridge formation - hence only 2 will ever be on.

    Effectively, I will switch 2 of them on for approx 20ms then off for 80ms, then switch the other 2 (ie reverse the output polarity) for 20ms then off again for 80ms - and so on in an endless loop. In other words, switching at 10hz with a 20% duty cycle.

    When I decide to switch one on I would ideally like it to go on within 1ms.

    By the sounds of it, the IGBT I selected may not be the best choice.