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

Effect of feedback on stability, Q. Effect of feedback on stability? Le...

Q. Effect of feedback on stability? Let us consider the direct transfer function of the unstable first-order system of Figure (a). The transfer function is given by whe

Calculate the supply voltage on the high-voltage side, Q. A 150-kVA, 2400/2...

Q. A 150-kVA, 2400/240-V, 60-Hz, single-phase transformer has the following parameters: R 1 = 0.2 , R 2 = 0.002 , X 1 = 0.45 , X 2 = 0.0045 , RC = 10 k, and Xm = 1.55 k,

Draw and explain a monostable multivibrator, Q. Draw and explain a monostab...

Q. Draw and explain a monostable multivibrator ? The monostable configuration consists of two amplifier stages interconnected in such a manner as to possess one stable state. T

Common emitter configuration, Common emitter configuration: even in co...

Common emitter configuration: even in common emitter configuration current relation is like is same like common bias configuration. For common emitter configuration output cha

Explain norton''s theorem procedure, Norton's theorem procedure: 1.  Re...

Norton's theorem procedure: 1.  Remove R L from the circuit. Search I N by shorting links output terminal. 2.  Search R N by short-circuit voltage source or open-circuit

Advantages of high level languages , Advantages of High  level  Languages...

Advantages of High  level  Languages a.It is  easy  to learn  write and debug  the program  written in high  level  languages. b.Programs are more  legible as compared to m

Prepayment meters, Prepayment Meters Usage of prepayment meters will e...

Prepayment Meters Usage of prepayment meters will extensively improve the revenue collection of the utilities. There are a number of ways in that prepayment assures revenue pr

Find the maximum kva rating as an auto- transformer, Q. A 5-kVA, 480:120-V,...

Q. A 5-kVA, 480:120-V, two-winding, 60-Hz, single-phase transformer has an efficiency of 95% while delivering rated load at rated voltage and 0.8 power factor lagging. This transfo

Block diagram of a 4-bit shift-right register using jkffs, Q. A shift regis...

Q. A shift register can be used as a binary (a) divide- by-2, and (b) multiply-by-2 counter. Explain. Q. Show a block diagram of a 4-bit shift-right register using JKFFs.

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