|(Image: Current Flow in a Diode)|
Thursday, April 26, 2012
Do you know what is conventional current in diode?
Generally we know,conventional current is responsible for the operation of current flow in forward biased PN diode.But,we do not know how this conventional current is been produced.Now,let us see..
Under forward bias ,+ve charges in p-type are repelled and -ve charges in n-type are repelled by the electric field.Hence it crosses the junction and creates a flow of current.
When an external DC is applied,the electrons from the n-type and holes from the p-type tries to cross the junction.In every recombination,one electron vanishes and enters in to p-type.In p-type one covalent bond is broken and it results with one free electron and one free hole.This free electron is attracted by the positive terminal.This is called conventional current.This results in continuous and large current flow.Thus depletion region is reduced.
NOTE:Conventional current flows in the direction opposite to that of the electron flow direction.