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Unread 02-03-2012, 21:34
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Matt Krass Matt Krass is offline
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Re: Jaguars vs Victors

Quote:
Originally Posted by techhelpbb View Post
Synchronous rectification on the black Jaguars.

Please keep in mind that people often use the body diodes of these MOSFETs as the anti-parallel high speed Schottky. So these diodes get hot and that heats up the MOSFET transistor as a whole.
I was aware of the Jaguars synchronous behavior, but I thought it wouldn't be a problem because, if I'm looking at my sketch correctly, when the off cycle occurs the terminals of the Jaguar reverse polarity and match those of the Victor, at roughly (but never at exactly the same time) that the Victors low side FETs disengage. Perhaps it just oversight on my part, but I don't believe this would be a problem, since the terminals would either be open at the Victor, or connected to the same node as the corresponding Jaguar terminals, not flowing any current?

It's entirely possible I'm missing something right in front of my face, am I?

Also, since the Victors don't have synchronous rectification (to the best of my knowledge) and only switch the low side (again, to the best of my knowledge) I suppose the body diode on the bottom FETs get's a work out when the Victor is in it's off cycle and the Jaguar isn't, I assume this is where your concern about heating comes in?

Matt
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Matt Krass
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