Acquire the best Transistor Circuit Assignment Help and tutor service to achieve superior grades!!

Home   Course  
Previous << || >> Next

MOST RELIABLE AND TRUSTWORTHY TRANSISTOR CIRCUIT ASSIGNMENT HELP & HOMEWORK WRITING SERVICES AT YOUR DOORSTEPS!

Question 1. FIGURE 1 shows a transistor connected in common-emitter mode. Using the Ebers-Moll equations for an npn transistor, estimate the value of the base emitter voltage, VBE, required to make
(i) the collector-emitter voltage, VCE, 5 volts
(ii) the collector current 9.95 mA.

Answer:

Determine VBE
The equation to find out IC is
IC = αFIEBS[exp(e/KT(VBE))-1]-ICBS[exp(-e/KT(VCE - VBE)-1]
Substituting the 0.98 known values in this
VCE = 5V
IC = 9.95mA
IEBS = ICBS =1×10-13
αF = 0.98
KT/e = 25mV
9.95×10-3 = 0.98×10-13[exp(VBE/(26×10-3 ))-1]-10-13[exp((-1)/(26×10-3 )(5-VBE))-1]
(9.95×10-3)/10-13 =0.98exp(VBE/(26×10-3 )) - 0.98 -exp((-5)/(26×10-3 )+VBE/(26×10-3 ))+1
9.95×1010 = 0.02+0.98exp(VBE/(26×10-3))-exp((-5)/(26×10-3) )+VBE/(26×10-3 ))
9.95×1010 = exp(VBE/(26×10-3 ))[0.98-exp((-5)/(26×10-3 ))]
9.95×1010 =exp(VBE/(26×10-3 ))×0.98
(9.95×1010)/0.98 = =exp(VBE/(26×10-3 ))
11.006×1010=exp(VBE/(26×10-3 ))
VBE/(26×10-3 ) = log(11.006×1010)
VBE = 286.168×10-3 =0.286V

SAVE DISTINCTION MARKS IN EACH TRANSISTOR CIRCUIT ASSIGNMENT WHICH IS WRITTEN BY OUR PROFESSIONAL WRITER!

Question 2. An npn transistor has the doping concentrations as given in TABLE A, where NDE and NDC are the emitter and collector donor concentrations and NAB the acceptor concentration of the base.

(a) Justify the assumption made in FIGURE 2(a) that the majority carrier densities nE, nB and nC can be regarded as being the same value as the doping densities NDE, NAB and NDC, respectively.

Answer: Justifications

Holes diffuse from emitter to collector and drift is negligible in the base region. The majority carrier densities are therefore considered as equal to doping concentrations.

(b) Determine the values of the unbiased minority carrier densities pE0, nB0 and PC0,

Answer:

PE0 = 2X1023

nB0 = 5X1020

Pco= 4x1022

HIRE PROFESSIONAL WRITER FROM EXPERTSMINDS.COM AND GET BEST QUALITY TRANSISTOR CIRCUIT ASSIGNMENT HELP AND HOMEWORK WRITING SERVICES!

Question 3. FIGURE 2(b) represents the carrier densities in the three neutral regions of the transistor under active conditions. The base-emitter junction is forward-biased by 0.6 volts and the base collector junction is reverse-biased by 1 volt.

The base-region is sufficiently thin (WB << LN, where LN is the electron diffusion length) as to allow us to assume a linear minority gradient dnB (x)/dx

(a) Calculate the values of pE(0), nB(0) and pc(0).

Answer: Determine

          Pn(0) = pno (eVA/KT)

=2 X10 23 X 26mV

52 X 1020

nB(0) = 5 X10 20 X 26mV

=130 X 1017

Pc(0)=4 X10 22 X 26mV

=104 X 1018

(b) Estimate the collector current density if the width of the base is 1.1 μm.

Answer: Jn=eDndn/dx

= (qDnnpbo/Wb).e(qvbe/kt)

7.33 X 1013

(c) Calculate the minimum cross-sectional area of the base if the transistor is to be capable of carrying 1 ampere.

Answer: The minimum cross sectional area
I = neµEA
A = 0.67mm2

WE HELP STUDENTS TO IMPROVE THEIR GRADES! AVAIL TOP QUALITY TRANSISTOR CIRCUIT ASSIGNMENT HELP AND HOMEWORK WRITING SERVICES AT CHEAPER RATE!

Question 4. Determine the most suitable transistor from TABLE B for use in the circuit of FIGURE 3. You may assume in all cases that the transistor is biased with VBE = 0.6 V.

Answer: From the table the most suitable will be BCY88 as this transistor is having the VCEO value lesser than the supply voltage.

VBE = 0.6V

Let us determine the quiscent values

Transistors

VCEQ=24-ic(RC+RE)

 

BC107

-42V

negative

BC109

-42V

negative

BCY88

5.0V

positive

NEVER MISS YOUR CHANCE TO EXCEL IN TRANSISTOR CIRCUIT ASSIGNMENT! AVAIL AFFORDABLE AND RELIABLE TRANSISTOR CIRCUIT ASSIGNMENTS HELP SERVICES OF EXPERTSMINDS.COM

Access our Teesside University Assignment Help services for various related units and courses such as: -

  • Semiconductor Physical Electronics Assignment Help
  • Electrical Supply and Distribution Assignment Help
  • Combinational and Sequential Logic Assignment Help
  • Statistical Process Control Assignment Help
  • Operational Amplifiers Assignment Help
  • Business Management Techniques Assignment Help
  • Electromagnetic Compatibility Assignment Help
  • Electrical Systems Protection Assignment Help
  • Control Systems and Automation Assignment Help
Tag This :- EM201912ABD14EE Transistor Circuit Assignment Help

get assignment Quote

Assignment Samples

    Advanced Accounting Assignment Help

    advanced accounting assignment help and Homework help - Why is the allocation of income tax expensefigure between members of a business combination important.

    Consumer Behavior Assignment Help

    consumer behavior assignment help - The project report is developed to launch the new product. The timeline for the activities are developed.

Get Academic Excellence with Best Skilled Tutor! Order Assignment Now! Submit Assignment