Switching characteristics, Electrical Engineering

Assignment Help:

Switching Characteristics

Switching  characteristics  of BJT  are shown  in figure. Due  to the presence of internal  capacitances BJT  cannot be  turned  instantly. Initially when base  emitter  voltage  is applied in CE  configuration leakage current  flows.  The collection current  begins  to rise after  some delay  time  and reaches at its  steady state  value. the time  from which  collector  current  starts  rising  to its  steady  state value  known  as rise time. BJT gets turned on in and collector emitter  voltages falls from  its maximum  value  forward voltage drop.

1431_Switching Characteristics.PNG

 

Till the forward  base  current is  maintained the BJT  remains in  on condition. As  the base emitter  voltage  is removed at a time t1 does not change for a  time ( there  its is  storage time in which the charges are removed from the base).  After  this time Ic begins to fall and collector voltage starts rising  for a time tf  ( fall time ) . in  fall time  decreases to leakage current  and voltage  rises  to vcc. Hence the turn off time  of BJT is  t off = ts +  tf. In conduction period of BJT a steady state  current  flows and  forward  voltage  drop  appears across the  collection emitter  junctions.

 


Related Discussions:- Switching characteristics

Why earthing is required for any electrical equipments, Why earthing is req...

Why earthing is required for any electrical equipments, domestic installation and service building etc? For TL coaches what is the minimum I.R. value needed for new wiring? An

Find current-voltage-resistance or power, 1.   Work out the  voltage for ...

1.   Work out the  voltage for the following arrangement of 1.5V cells : (to achieve a pass grade, solve problems with cells in series, parallel and series-parallel) 2.

Cellular telecommunication sector - software defined radio, Cellular teleco...

Cellular telecommunication sector - Software Defined Radio As of now, every cell phone transmits and receives information through a speci?c standard. If we have to change the s

Salary, electrical designer salary above 6years experience, in singapore

electrical designer salary above 6years experience, in singapore

What do you mean by pinch off voltage, Q. What do you mean by Pinch off vol...

Q. What do you mean by Pinch off voltage? As the voltage Vds is increased from 0 to a few volts, the drain current will increase as  determined by Ohm's law and the plot of Id

What are shift register counters, What are Shift Register Counters? Two...

What are Shift Register Counters? Two of the main common types of shift register counters are the Ring counter and the Johnson counter and They are basically shift registers wi

Obtain the time domain functions, Let ω = 2π × 60 rad/s corresponding to a ...

Let ω = 2π × 60 rad/s corresponding to a frequency of 60 Hz. (a) Consider v(t) = 100 √2 cos(ωt + 30°) V and i(t) = 10 √2 sin(ωt + 30°) A. Find the corresponding phasors ¯V and ¯

Torque angle, describe torque angle in ships electrical propulsion system

describe torque angle in ships electrical propulsion system

Develop a general expression for the force, Consider an electromagnet, as s...

Consider an electromagnet, as shown in Figure, which is used to support a solid piece of steel and is excited by a coil of N = 1000 turns carrying a current i = 1.5 A. The cross-se

Magnetic flux and flux density, Magnetic flux and flux density Magnetic...

Magnetic flux and flux density Magnetic flux is the amount of the magnetic field (or the number of lines of force) formed by a magnetic source. The symbol represented magnetic

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