Npn bjt with forward-biased, Electrical Engineering

Assignment Help:

NPN BJT with forward-biased:

An NPN transistor can be referred as two diodes along with a shared anode. In common operation, the base-emitter junction is forward biased and the base-collector junction is reverse biased. In an NPN transistor, for instance, while a positive voltage is applied to the base-emitter junction, the equilibrium among the thermally generated carriers and the repelling electric field of the depletion region turns unbalanced, permitting thermally excited electrons to inject into the base region. These electrons wander or "diffuse" via the base from the region of high concentration near the emitter in the direction of the region of low concentration near the collector. The electrons in the base are termed as minority carriers since the base is doped p-type that would make holes the majority carrier in the base.

To minimize the percentage (%) of carriers which recombine before arriving at the collector-base junction, the base region of transistor must be thin enough which carriers can diffuse across it in much less time than as compared to the semiconductor's minority carrier lifetime. Particularly, the thickness of the base has to be much less than diffusion length of the electrons. The collector-base junction is reverse-biased, and thus the little electron injection takes place from the collector to the base, but electrons that diffuse by the base towards the collector are swept into the collector via the electric field in the depletion region of the collector-base junction. The thin shared base and asymmetric collector-emitter doping is what distinguishes a bipolar transistor from two separate and oppositely biased diodes that are connected in series.


Related Discussions:- Npn bjt with forward-biased

Calculate the current flow using norton theorem, Calculate the current flo...

Calculate the current flow in 30Ω resistor for the circuit in figure using Norton Theorem.

Back emf, Transistor Switching Circuit Design a) Sketchy a schematic d...

Transistor Switching Circuit Design a) Sketchy a schematic diagram showing how a transistor can be used to control the operation of a relay b) Determine what is meant by ba

Explain the working of direct memory access controller, Explain the various...

Explain the various modes in which DMAC works. Working of Direct memory access controller: The modes of operation has demand mode, block mode, single mode and cascade mode.

Discuss electrical properties of insulating materials, Discuss electrical p...

Discuss electrical properties of insulating materials. Electrical properties of an insulating material are As Follows: Insulation resistance - It is the property, through

Cmp compare instruction , CMP Compare Instruction This instruction is ...

CMP Compare Instruction This instruction is used to compare the contents  of register  or memory  with accumulator the contents of the operand remain  unaffected. There are tw

How many wavelengths long is the line, Q. A transmission line with a dielec...

Q. A transmission line with a dielectric (εr = 3.5) is 100 m long. At a frequency of 10 GHz, how many wavelengths long is the line?

Why do we cascade amplifiers, Q. Why do we cascade amplifiers? Why is RC co...

Q. Why do we cascade amplifiers? Why is RC coupling the most widely used coupling between 2 stages of a cascading amplifier? The voltage or power gain or frequency response obt

Solid mensuration, reflections, journey about the subject solid mensuration...

reflections, journey about the subject solid mensuration

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd