Re: A prospective MOSFET driver

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Jan Wagner by way of Terry Fritz <twftesla-at-qwest-dot-net>" <jwagner-at-cc.hut.fi>


> For anyone interested, I've found that a Schottky diode is needed between
> base & collector in
>  http://hot-streamer-dot-com/temp/TCH2DRVR.gif, cathode to base.  I will use
> a 1N5818.  Keeps the b:c junction from conducting which, I find, takes ~1
> us to recover using a ZTX949 for Q1.

Variation of the standard trick for NPN bipolars? Also keeps Q1 out of
saturation, thus faster switching.
There "was a book" ;) that had some examples on active pull down / pull up
circuits for mosfet gate drives like in your schematic. I think it was
Abraham Pressman, "Switch mode power supply design", IIRC. I'll try to dig
it out...

cheers,

 - Jan

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 Jan OH2GHR