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

Explain the operation of n-channel fet, Q. Explain the operation of N-chann...

Q. Explain the operation of N-channel FET? Transistor is a linear semiconductor device that controls current with the application of a lower-power electrical signal. Transistor

ELECTRIC DRIVES, BLOCK DIAGRAM OF DIGITAL CONTROL OF ELECTRIC DRIVES

BLOCK DIAGRAM OF DIGITAL CONTROL OF ELECTRIC DRIVES

On which hysteresis loss is least depend, Hysteresis loss least depends on ...

Hysteresis loss least depends on (A) Frequency.                         (B) Magnetic field intensity. (C) Volume of the material.     (D)Grain orientation of material.

What are the various tones used in stronger telephony, Q. What are the vari...

Q. What are the various tones used in stronger telephony? When called party line is obtained, exchange control equipment transmits out the ringing current to telephone set of t

What can explain failure of relative ppp to hold in reality, Q. What ...

Q. What can explain the failure of relative PPP to hold in reality? Answer: Government procedures of the price level differ from country to country. One cause for thes

Explain the asynchronous up-down counters, Explain the Asynchronous Up-Down...

Explain the Asynchronous Up-Down Counters? In some applications a counter must be able to count both down and up and the circuit below is a 3-bit up-down counter. It counts do

Application of electrochemical grinding, Explain the working principle, Sur...

Explain the working principle, Surface finish, material removal, accuracy,advantages and application of Electrochemical Grinding(ECG). (a) In electro chemical machining of pure

What are the five stages in a dlx pipeline, The five stages of DLX pipeline...

The five stages of DLX pipeline is:- ? Operand location ? Number of explicit operands per instruction ? Operand storage in the CPU ? Operations ? Type and size of o

Give an account on the operation of the oupled amplifier, Q. Give an accoun...

Q. Give an account on the operation of the R-C coupled amplifie r. When a.c. signal is applied to the base of the first transistor, it appears in the amplified form across its c

Show the enhancement of mosfet, Q. Show the Enhancement of MOSFET ? Her...

Q. Show the Enhancement of MOSFET ? Here also the slab of p type material called the substrate is provided. The substrate is connected to a source terminal. Many discrete devic

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