PN Junction Diode DefinitionA PN junction diode is defined as a semiconductor device that allows current to flow in one direction in forward bias and blocks current in reverse bias.Forward BiasIn forward bias, the p-type region is connected to the positive terminal and the n-type to the negative terminal, reducing the depletion layer and allowing current flow.Reverse BiasIn reverse bias, the p-type region is connected to the negative terminal and the n-type to the positive terminal, increasing t