Re: Can you help with these waveforms? (fwd)

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: List moderator <mod1@xxxxxxxxxx>



---------- Forwarded message ----------
Date: Wed, 30 May 2007 21:20:54 -0400
From: Skip Malley <skip@xxxxxxxxxxxxxxx>
To: Tesla list <tesla@xxxxxxxxxx>
Subject: Re: Can you help with these waveforms? (fwd)

Greg,
any diode across a FET or other switching transistor should be of the 
ULTRA-Fast type or Schottky type.  Schottky diodes are available for 
up to 100 or maybe 200 Volts.  Beyond that use Ultra-Fast.  If asking 
for assistance and suggestions, please provide a piece of schematic 
and indicate the point of scopeing.

Happy coiling.

Skip

At 10:20 AM 5/30/2007, you wrote:
>Original poster: List moderator <mod1@xxxxxxxxxx>
>
>
>
>---------- Forwarded message ----------
>Date: Thu, 31 May 2007 00:00:52 +1000
>From: Mr Gregory Peters <s371034@xxxxxxxxxxxxxxxxx>
>To: Tesla list <tesla@xxxxxxxxxx>
>Subject: Re: Can you help with these waveforms? (fwd)
>
>Actually, problem sorted now. I had the diode in the wrong spot. Put
>it in "reverse parallel" with the transformer rather than the FET and
>solved the problem. It sure gets hot though! Is there any way of
>reducing this inductive kick? Maybe a slower turn off time for the
>mosfet?
>
>Cheers,
>
>Greg