TI Mosfet Driver IC connecting in parallel

Discussion in 'General Electronics Chat' started by surfline, Feb 5, 2010.

  1. surfline

    Thread Starter Active Member

    Aug 12, 2009
    30
    0
    Hi,


    I have been able to successfully use the TI UCC27325P Dual Mosfet Driver IC (Datasheet here: http://focus.ti.com/lit/ds/symlink/ucc27325.pdf) with a single input and output, however I'm am trying to set it up with double the current by hooking up the input and output in parallel as shown in the datasheet. I have it hooked up exactly as its shown on page 8, figure 4 on the datasheet. When I turn it on it quickly gets hot and blows up / cracks. What am I doing wrong?


    The Mosfet driver IC input is from PIC microcontroller PWM pin and the IC mosfet driver is driving four mosfets switching 30amp motor load.



    Thanks,
    Surfline
     
  2. SgtWookie

    Expert

    Jul 17, 2007
    22,182
    1,728
    I'm wondering why you're using four MOSFETs?

    What's your PWM frequency?

    Post your circuit and board layout.
     
  3. surfline

    Thread Starter Active Member

    Aug 12, 2009
    30
    0
    Using four mosfets to split up the excessive heat and current from switching 30 amp motor load. Gets really hot!

    PWM frequency = 20Khz.

    The circuit is simple: PIC PWM Output -> Mosfet IC Driver -> Mosfet Gates

    The Drain is Moter - and the source is GND. M+ = 12 V. So when input to mosfet gate is high / on the M- gets shorted to GND, and motor turns on.
     
    Last edited: Feb 7, 2010
  4. SgtWookie

    Expert

    Jul 17, 2007
    22,182
    1,728
    I hate sounding like a broken record here, but you'll save everyone a lot of time if you just post your schematic AND board layout.

    You will also need to include the length and gauge of the wiring from your power supply and to the motor.
     
  5. SgtWookie

    Expert

    Jul 17, 2007
    22,182
    1,728
    It's not hard to attach your schematic and board layout.

    .PNG format files are preferred; they are compact, easy to view, and are not lossy like .jpg files are. You can make a screen print (Ctrl+PrintScreen) in your schematic and board software, and then paste the image into MS Paint. Save as type .png files.

    Use the Go Advanced button, then Manage Attachments to upload the files from your computer.
     
Loading...