Storage delay and transistor alpha- beta, Electrical Engineering

Assignment Help:

Turn-on, turn-off, and storage delay:

The Bipolar transistor shows a few delay characteristics while turning on and off. Most of the transistors, and particularly power transistors, show long base storage time that limits maximum frequency of operation in switching applications. One technique for reducing this storage time is using a Baker clamp.

Transistor 'alpha' and 'beta':

The proportion of electrons capable to cross the base and reach the collector is a measure of the BJT (bipolar junction transistor) efficiency. The heavy doping of the emitter region and light doping of the base region origin several electrons to be injected from the emitter into the base than as compared to the holes to be injected from the base into the emitter. The common-emitter current gain is presented by βF or hfe; it is approximately the ratio of the DC collector current to the DC (direct current) base current in forward-active region. It is generally greater than 100 for small-signal transistors but can be smaller in transistors intended for high-power applications. An additional significant parameter is the common-base current gain, αF. The common-base current gain is almost the gain of current from emitter to collector in the forward-active region. This ratio generally has a value that is close to unity; approximately between the 0.98 and 0.998. Alpha and beta are more precisely related through the following identities (NPN transistor):

αF = Ic/IE

βF = Ic/IB

βF = αF / (1- αF) ↔ αF = βF / (βF +1)


Related Discussions:- Storage delay and transistor alpha- beta

Common source drain and transfer characteristics of a jfet, Q. Draw the com...

Q. Draw the common source drain and transfer characteristics of a JFET. How are they useful? The graph below shows  variation of the drain current Id as a function of the drain

How to convert binary to decimal number, Q. How to convert Binary to Decima...

Q. How to convert Binary to Decimal number system? It is extremely easy to convert from a binary number to a decimal number. As like the decimal system, we multiply each digit

Compute the pull on the plunger, Q. A sectional view of a cylindrical iron-...

Q. A sectional view of a cylindrical iron-clad plunger magnet is shown in figure. The small air gap between the sides of the plunger and the iron shell is uniform and 0.25 mm long.

Explain isolated i/o scheme, Explain isolated I/O scheme. In I/O mapped...

Explain isolated I/O scheme. In I/O mapped I/O scheme the addresses allocated to memory locations can also be assigned to I/O devices. Because the same address may be assigned

Binary to octal conversion, Binary  to Octal Conversion To convert a b...

Binary  to Octal Conversion To convert a binary  number into octal  divide the number into  group  of three  bits each  starting from the least significant bit. Then put equiva

100 line exchange with two-motion line finders, In this design, there are 2...

In this design, there are 24 line finders. If any of the 100 subscribers has to get access to any of 24 two-motion selectors, it is necessary that every line finder is capable of r

Define waves and transmission lines, Q. Define waves and transmission lines...

Q. Define waves and transmission lines? In basic circuit theory we neglect the effects of the finite time of transit of changes in current and voltage and the finite distances

Change of phase, Write an m-file "myfourier.m" which takes two images, comp...

Write an m-file "myfourier.m" which takes two images, computes FFT, phase and amplitude and swaps the amplitudes between two images. function myfourier im1=imread('cameraman.pn

What is traffic engineering, Q. What is Traffic Engineering? Traffic en...

Q. What is Traffic Engineering? Traffic engineering provides the foundation for analysis and design of telecommunication network to carry a given traffic at a particular loss p

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