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

Adi add immediate instruction , ADI Add Immediate  Instruction The  b...

ADI Add Immediate  Instruction The  bit  data specified in the instruction  is  directly  added with  contents of accumulator and result  of operation is stored  in the  accum

Give some applications of nichrome, Give some applications of nichrome. ...

Give some applications of nichrome. Nichrome is an alloy of iron, chromium, nickel and manganese. This is used for electric iron, for making heating elements and another hea

Homework, voice signal is measured at 3.21692v and resides in an interval f...

voice signal is measured at 3.21692v and resides in an interval from 3.20v to 3.30. How big is an interval? MAx possible voltage?

Describe schmitt trigger, a) Describe Schmitt trigger with the help of tran...

a) Describe Schmitt trigger with the help of transfer characteristics. b) Also get the expression of hysteresis voltage VH and output waveform for sinusoidal input signal

Growth in communications, The growth in communications over the past 60 yea...

The growth in communications over the past 60 years has been phenomenal. The invention of the transistor in 1947 and the integrated circuit and laser in 1958 have paved the way to

Automatic voltage booster, Automatic Voltage Booster The functioning o...

Automatic Voltage Booster The functioning of Automatic Voltage Booster (AVB) is same to in which of the series capacitor. Automatic Voltage Booster is an on-load tap changer.

Explain the different coupling schemes used in amplifiers, Q. Explain the d...

Q. Explain the different coupling schemes used in amplifiers? When amplifiers are cascaded, it is necessary to use a coupling network between the output of one amplifier and th

Electronic photo flash, Q. Electronic Photo Flash? A simplified schemat...

Q. Electronic Photo Flash? A simplified schematic diagram of the electric circuit of an electronic photo flash typically used on cameras is shown in Figure 7.7.1. By passing a

Forward and reverse-active in bipolar junction transistor, Forward and Reve...

Forward and Reverse-active in Bipolar Junction Transistor: Forward-active (or simply, active): The base-collector junction is reverse biased and base-emitter junction is

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