Electronics and Communication Engineering Questions and Answers
Prepare for your Electronics and Communication Engineering exams/aptitude tests, assess your knowledge of electronics and communication equipment with these ECE questions and answers.
Prepare for your Electronics and Communication Engineering exams/aptitude tests, assess your knowledge of electronics and communication equipment with these ECE questions and answers.
In a bipolar transistor, the barrier potential is
0
a total of 0.7 V
0.7 V across each depletion layer
0.35 V
Correct answer is C
Since there are two p-n junctions, there are two depletion layers and 0.7 V across each layer.
30 pA
40 pA
50 pA
60 pA
Correct answer is B
By increasing the temperature by 10°C, Io becomes double. So by increasing temperature by 20°C, Io becomes 4 times the initial value... and it is 40 PA.
A transistor has two p-n junctions. The batteries should be connected such that
both junctions are forward biased
both junctions are reverse biased
one junction is forward biased and the other is reverse biased
none of the above
Correct answer is C
Emitter-base junction is forward biased and base collector junction is reverse biased.
The number of doped regions in PIN diode is
1
2
3
1 or 2
Correct answer is B
A PIN diode has p and n doped regions separated by intrinsic layer.
0 to 200 Ω
200 - 400 Ω
200 Ω and above
400 Ω and above
Correct answer is D
R = (6-2/10x10-3) = 400Ω.
R must be at least 400Ω so that current in LED does not exceed 10 mA.