Explain working of bipolar junction transistors, Electrical Engineering

Assignment Help:

Q. Explain working of Bipolar junction transistors?

The family of bipolar junction transistors has two members: the npn BJT and the pnp BJT. Both types contain semiconductor junctions which operate with bipolar internal currents consisting of holes and electrons. These are illustrated in Figure along with their circuit symbols.

1371_Bipolar junction transistors.png

The emitter in the circuit symbol is identi?ed by the lead having the arrowhead. The arrow points in the direction of conventional emitter current ?ow when the base-emitter junction is forward biased. A transistor can operate in three modes: cutoff, saturation, and active. In the active mode, for an npn BJT, the base-emitter junction (BEJ) is forward-biased by a voltage vBE, while the collector-base junction (CBJ) is reverse-biased by a voltage vCB. Thus for an npn BJT, as shown in Figure (a), iB and iC are positive quantities such that iB + iC = iE. For a pnp BJT on the other hand, in the active region, the base-emitter and collector-base voltages are negative, and  currents iB, iC, and iE are all negative quantities such that iE = iB + iC, that is to say, the bias voltages as well as current directions are reversed compared to those of an npn BJT.


Related Discussions:- Explain working of bipolar junction transistors

Determine the voltage across the capacitor, (a) Let a unit impulse of curre...

(a) Let a unit impulse of current i(t) = δ(t) be applied to a parallel combination of R = 3 and C = 1/2 F. Determine the voltage vC(t) across the capacitor. (b) Repeat (a) for

State norton''s theorem, Norton's Theorem Nortons Theorem states: "A...

Norton's Theorem Nortons Theorem states: "Any linear circuit containing several energy sources and resistances can be replaced by a single Constant Current generator in para

Substations, How to calculate Electrical losses by transformation

How to calculate Electrical losses by transformation

Pn-junction under bias, Q. pn-Junction under Bias? Let an external sour...

Q. pn-Junction under Bias? Let an external source be connected between the p- and n-regions, as shown in Figure (a). (b) shows the circuit representation of the pn-junction or

Digital electronics, design 4 bit binary coded decimal to excess 3

design 4 bit binary coded decimal to excess 3

#title.MIPS assembly language code., Given the INPUT: • An array of 64-bit ...

Given the INPUT: • An array of 64-bit unsigned integer elements stored in the memory starting at a known location SOURCE. • The size of the array (i.e., number of elements) stored

Dc motor control, how thyristor work in speed control??

how thyristor work in speed control??

Cmos integrated circuit design, design using softwares (LEdit7, LTspice) t...

design using softwares (LEdit7, LTspice) the project has many aspects and I would like you to check them on the website with my personal password. in the project specifications (d

Live human detection robot, which simulation software is better for this p...

which simulation software is better for this project, and how can i simulate it?

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