Semiconductor Diodes • A diode is a very useful non-linear device • It allows current to flow in one direction and prevents it flowing in the other Anode Cathode I Diode Operation • When a positive voltage is applied across the diode then current will flow • The diode is said to be forward biased • When a negative voltage is applied then the diode is reverse biased and no current will flow Diode Characteristic Curve Forward Biased Diode • A positive voltage is applied to circuit so current will