So I'm looking for ideas, and information.

I have 0.05 ohm shunt resistor which I need to protect from overcurrent=20
(effectively overvoltage).   It's measuring steady-state current, and=20
also being used for overcurrent trip purposes.  In certain=20
very-high-current 'dead short' situations, this poor component becomes=20
less of a resistor and more of a fuse - I'd like to prevent that,=20
bypassing some of the current long enough for the trip to occur - a few=20
ms at most.

The obvious cheap solution here is to do some sort of tvss-like device=20
around the unit to bypass some of the current once the voltage across=20
the resistor rises to a certain point.   And looking at the curves of=20
the B1100 Schottky diode which is a standard part around here, it looks=20
like I might be able to just put one forward-biased across the resistor,=20
and use it in sort of tvss-mode...

My mental picture of a diode is that below Vf there is minimal if any=20
current conducted.  Is this an accurate mental picture?   What current=20
will flow if you 'bias' a schottky diode at say 0.2V?  I'm not worried=20
about capacitance more than what I'd call 'leakage current' (in the=20
forward direction though).

Is there something else I should be using instead?

-forrest

--=20
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