On Mon, 11 Jan 2010 08:25:42 -0000, "N_Cook" put
finger to keyboard and composed:

But,unlike zeners , are they guaranteed to go short circuit if they end up
in what becomes a sustained overvoltage rather than just a transient
situation ? or 2 different clases of TVS ?

I watch various hard drive forums. HDs nowadays use TVS diodes on
their +5V and +12V rails. A sustained overvoltage from, say, a 19V
laptop adapter always (?) shorts the 12V diode, unless it is protected
by a fusible zero-ohm resistor.

- Franc Zabkar
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