Storage delay and transistor alpha- beta, Electrical Engineering

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)

Posted Date: 1/10/2013 6:38:25 AM | Location : United States

Related Discussions:- Storage delay and transistor alpha- beta, Assignment Help, Ask Question on Storage delay and transistor alpha- beta, Get Answer, Expert's Help, Storage delay and transistor alpha- beta Discussions

Write discussion on Storage delay and transistor alpha- beta
Your posts are moderated
Related Questions
SHLD Store HL pair Direct Instruction This  instruction is used to store the contents of HL  register  pair to  memory  address specified  in the  instruction and the  next ad

Q. Show Balanced three-phase loads? Three-phase loads can be connected in either wye (also known as star or Y) or delta (otherwise known as mesh or ). If the load impedances i

Describe the three main sources of power dissipation in CMOS logic. Hence calculate the power dissipated in a CMOS ASIC of 40,000 gates operating at a frequency of 133MHz with a s

Q. Commercial FM radio broadcasting? Commercial FM radio broadcasting utilizes the frequency band of 88 to 108 MHz for the transmission ofmusic and voice signals. The carrier

Partial derivatives - Transistor hybrid model: The partial derivatives are taken by keeping the collector voltage or base current constant as pointed out by the subscript atta

ANI AND Immediate  with Accumulator Instruction 8 bit  data specified  in the  instruction is logically  AND with the  contents  of the  accumulator. The result is stored  in

Explain the factors affecting permeability and hysterisis loss. Factors affecting permeability and hysterisis loss: When the initial permeability is high, the hysterisis los

Q. Explain digital Storage Oscilloscope (DSO) with neat diagram, (b) Give the difference between analog and digital storage oscilloscope.   Principle of operation : The availa

what is the formula of lime water

Gaussian derivatives Generate Gaussian kernels for a given scale "sigma", and display the kernel. The size of the kernel should be floor(3*sigm)+1; (i) Write an m-file "