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

What are transistor amplifiers, Q. What are transistor amplifiers? What is ...

Q. What are transistor amplifiers? What is meant by efficiency of an amplifier? What is amplifier coupling? The AMPLIFIER is a device that enables an input signal to control an

Mr GZ, HOW TO PERFOM AUTO DIALLING USING GSM MODULE

HOW TO PERFOM AUTO DIALLING USING GSM MODULE

Electrical System Design, List four sources of information which are essent...

List four sources of information which are essential to the designer of this electrical installation

Simplified operation on transistor, Simplified operation: Figu...

Simplified operation: Figure: Simple circuit to show the labels of a bipolar transistor. The essential value of a transistor comes from its capability to make use

Neutral line in transformer, thus secondary winding of transformer consists...

thus secondary winding of transformer consists of neutral line or not?

memory to register , Memory  to Register This  instruction is used to...

Memory  to Register This  instruction is used to copy the contents of a memory  locations whose  address is specified by the HL register  pair to any register. Before  using th

Compute the current loss in the lines, Q. Consider a 240-V supply feeding a...

Q. Consider a 240-V supply feeding a resistive load of 10 kW through wires having a total resistance of R = 0.02 . For the same load, let a 120-V supply be used with a total wire

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