|
|
| |
Semiconductors are made from material somewhere between the ranges of
conductors and nonconductors. Semiconductors, basically, are designed
to do one of three things: (1) stop the flow of electrons, (2) start
the flow of electrons, or (3) control the amount of electron flow. A
semiconductor diode is a two-element solid state electronic device.
It contains what is termed a "P" type material connected to a piece
of "N" material. The union of the "P" and "N" materials forms a PN
junction with two connections. The "anode" is connected to the P
material; the "cathode" is connected to the N material. A diode is,
in effect, a one-way valve. It will conduct current in one direction
and remain non conductive in the reverse direction. When current
flows through the diode, it is said to be "forward biased." When
current flow is blocked by the diode, it is "reverse biased." When a
diode is reverse biased, there is an extremely small current flow;
actually, the current flow is said to be "negligible." When the P and
N are fused together to form a diode, it can be placed in a circuit.
The P material is connected to the positive side of the battery and
the N material is connected to the negative side of the battery.
Connected in this manner, current will flow. If connected in the
reverse manner, current will not flow.
|
|
|
|
|
