On Fri, Nov 21, 2003 at 10:00:42AM +0800, john chung wrote:
> Can someone please explain what does "latchup" exactly does?

The explanation you got was really good, I liked it.  I'll give you
another explanation:

Stops everything, consumes large amounts of current, and if the supply
is willing to provide that current it may exceed the thermal limits of
the chip and cause destruction.

I'm not sure "exactly" though.  That's something for a chip designer.

Some interesting references via google ...

http://www.csee.umbc.edu/~plusquel/vlsiII/slides/mos3.html
shows diagrams of chip area and describes the effect

http://semiconductorglossary.com/default.asp?searchterm=latch+up%2C+latchup%2C+latch-up
has a brief description

--
James Cameron    mailto:quozl@us.netrek.org     http://quozl.netrek.org/

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