On 4/21/06, Alan B. Pearce <A.B.Pearce@rl.ac.uk> wrote:
> >That's part of the driver for the FETs. I can post that part of the
> >circuit too, but I think it is unlikely to be part of the problem.
>
> Actually I think that is precisely where your problem is. The bottom FET
> will switch faster than the top one in the totem pole, because you have a
> capacitor on the gate of the top FET, but not the bottom one. Hence when the
> top one is on, bottom off, and you swap states there will be significant
> shoot through current while the top one turns off.

  I'm afraid Allan has right. You have large timing difference in your
FETs N and P driving for half bridges.  I didn't look at the
datasheet, but the RC (where R is equivalent resistor in the gate
circuit and C is the equivalent Cis + your capacitors)
must be identical for both FETs.

Vasile


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