19-07-2006, 09:15
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I live for the details.
 FRC #3620 (Average Joes) Team Role: Engineer
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Join Date: Jan 2003
Rookie Year: 1996
Location: Southwestern Michigan
Posts: 3,647
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Re: victor mosfets
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Originally Posted by sciguy125
Alright, now just for a sanity check, MOSFETs short when they fail from too much current, right? I've seen several failed Victors and I'm reasonably sure that's what they do, but I can't remember.
Also, I have an internship this summer and I'm running tests on various devices and it seems that MOS shorts when it fails(unless of course you attack the gate). I'm working at the wafer level, but I don't see why things would change for a power transistor.
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Short-circuit failure is typical on the wafer level. When large die are mounted and bonded to a single-device leadframe (e.g., TO-220) the weak link after such a failure is usually the source bonding filaments (for an n-channel device). Assuming sufficient fault current is available, these will burn open fairly quickly after the die has failed short. The result is that most discrete package power MOSFET failures are open-circuit by the time things cool off and you get to inspect the damage.
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Richard Wallace
Mentor since 2011 for FRC 3620 Average Joes (St. Joseph, Michigan)
Mentor 2002-10 for FRC 931 Perpetual Chaos (St. Louis, Missouri)
 since 2003
I believe in intuition and inspiration. Imagination is more important than knowledge. For knowledge is limited, whereas imagination embraces the entire world, stimulating progress, giving birth to evolution. It is, strictly speaking, a real factor in scientific research.
(Cosmic Religion : With Other Opinions and Aphorisms (1931) by Albert Einstein, p. 97)
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