Re: gEDA-user: LED in reverse

[DJ Delorie <dj@xxxxxxxxxxx>]

> How is it possible that the LED withstands 20mA in forward and is
> destroyed by 0.5mA in reverse?

Trick question.  Imagine an IDEAL current source.  It would be able to
produce 0.5mA across an air gap, for example.  Imagine how many volts
would be required to do that.

Now imagine that ideal current source across a diode.  In the forward
direction, it would produce a fraction of a volt until the diode
started conducting, no harm.  In the reverse direction it would apply
enough voltage to hit the breakdown, at which point the diode starts
conducting.


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