Q. 173.7( 3 Votes )

(i) Explain with the help of a diagram the formation of depletion region and barrier potential in a pn junction.

(ii) Draw the circuit diagram of a half wave rectifier and explain its working.

Answer :

(i)



The formation of the p-n junction is due to the concentration gradient difference across p-side and n-side. It involves the diffusion of the holes from the p-type semiconductor to the n- type and the diffusion of electrons from n-type to p-type. When an electron diffuses it leaves an immobile positive charge and when a hole diffuses it leaves and immobile negative charge. The diffusion of these carriers occur continuously across the junction .This causes a layer of immobile positive and negative charges on both the sides of the junction. The layer is known as the depletion layer or region.


(ii) Half wave rectifier



When an AC input is applied across the primary coil, there is a corresponding potential difference developed across the ends of the secondary coil. We consider that in half cycle of input signal, the end with the positive sign acts as positive and other acts as negative end of the battery.The diode is thus forward biased and we get an output across the resistor .


In the second cycle of the input AC signal the parity of the secondary coil reverses and hence, the diode is in reverse bias and thus a zero output is obtained across load resistor due ti a very high resistance by the diode.


Since, we get the output for half cycle of the input ac signal, the diode is thus called half-wave rectifier.



Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Related Videos
Know all about InfertilityKnow all about InfertilityKnow all about Infertility39 mins
Clear all concepts about AIDSClear all concepts about AIDSClear all concepts about AIDS46 mins
All About Faraday's lawAll About Faraday's lawAll About Faraday's law55 mins
Get to know all about Immune SystemGet to know all about Immune SystemGet to know all about Immune System60 mins
Biotech Application- All Concepts at FingertipsBiotech Application- All Concepts at FingertipsBiotech Application- All Concepts at Fingertips73 mins
Revision Class | All Formulas of ElectrodynamicsRevision Class | All Formulas of ElectrodynamicsRevision Class | All Formulas of Electrodynamics63 mins
All Important Questions on Bio MoleculesAll Important Questions on Bio MoleculesAll Important Questions on Bio Molecules46 mins
Know all about Colligative PropertiesKnow all about Colligative PropertiesKnow all about Colligative Properties50 mins
Know All About Types of RelationsKnow All About Types of RelationsKnow All About Types of Relations53 mins
All concepts of Hybridisation in 60 minutesAll concepts of Hybridisation in 60 minutesAll concepts of Hybridisation in 60 minutes41 mins
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
caricature
view all courses
RELATED QUESTIONS :