On 06/04/2016 06:47 AM, Stormin Mormon wrote:
On 6/3/2016 1:40 PM, Mark Lloyd wrote:

The LED itself regulates voltage. That's what a diode does.


http://www.merriam-webster.com/dictionary/diode

Simple Definition of diode

: an electronic device that allows an electric current to flow in
one direction only

Source: Merriam-Webster's Learner's Dictionary


A very simple definition that is sort of correct but leaves out a lot of
stuff.

A diode has a threshold voltage. It the supplied voltage is less than
that, there will be no current. Otherwise the diode will conduct. It
will conduct as much as needed to limit the voltage across it to the
threshold. This means a diode may conduct excessive current if nothing
is done to limit it. This is frequently a resistor in series.

An important thing about a diode is that the threshold is different for
each polarity. That simple definition is correct when the voltage is
between one threshold and the other.

When the diode is in series, it will have a voltage drop equal to the
threshold voltage (which threshold depends on polarity).

BTW, I know that semiconductor junctions are even more complex than that.

--
Mark Lloyd
http://notstupid.us/

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