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

Determine the remaining voltages and currents, Q. Some element voltages and...

Q. Some element voltages and currents are given in the network con?guration of Figure. Determine the remaining voltages and currents. Also calculate the power delivered to each ele

Plc and control system analysis, The assignment is to plan, design and writ...

The assignment is to plan, design and write a PLC program on the FX Training Software using a PART SUPPLY CONTROL SYSTEM based on the requirement specification outlined be

Explain the chemical properties of insulating materials, Explain the chemic...

Explain the chemical properties of insulating materials. Chemical properties - Chemical resistance: Presence of gases, acids, water, alkalies and salts influences different

Define causal system - discrete time systems, Define Causal System - Discre...

Define Causal System - Discrete Time Systems? A causal system is one which produces an output only when there is an input. All physical systems are causal. In general, a causal

Find the decibels of improvement in signal-to-noise ratio, If a compressor ...

If a compressor in a system can change a message crest factor from 3.2 to 2, while maintaining its peak amplitude constant, find the decibels of improvement in signal-to-noise rati

Explain the asynchronous decade counter, Explain the Asynchronous Decade Co...

Explain the Asynchronous Decade Counter? The binary counters earlier introduced have two to the power n states. But the counters with states less than this number are as well

Mixed mode simulator, Mixed Mode Simulator: The circuit is preproc...

Mixed Mode Simulator: The circuit is preprocessed. The test points and waveform markers are located in input and output of the circuit. GND net is set like reference net.

Fourier Series, State by inspection (i.e. without performing any formal ana...

State by inspection (i.e. without performing any formal analysis) all you can about each of the periodic waveforms shown in FIGURE 1 in terms of their Fourier series when analysed

Pulsed OFDM odulation for ultrawideband communication, i have selected this...

i have selected this paper as my semester project according to teacher we have to fully implement it. i need its full written matlab code simulink model and results. can you help m

What is ohmmeter, What is ohmmeter An ohmmeter is an instrument for mea...

What is ohmmeter An ohmmeter is an instrument for measuring resistance

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