On Thu, 20 Apr 2006 08:29:57 -0500, John Fields
<jfields@xxxxxxxxxxxxxxxxxxxxx> wrote:
How much current would you have to feed through the diode to get a
3.3 volt drop across it in the forward direction?
About 59-60mV per decade at room temp for ideal diodes, based on the
differential of the simple EM equation.... which would produce a
great deal of current, cranked up to 3.3V. Impossible amounts, if
there wasn't another effect operating.
There is a resistive component that can vary a lot from diode type to
type. For example, the 1N4148 exhibits about 0.6 ohms (see the Rs
figure in a Spice model.) That will limit the current, but not so
much as to survive 3.3V.
It's probably open or nearly so.
Jon