Electrical Engineering (EE) Exam  >  Electrical Engineering (EE) Questions  >  The total thermal resistance of a power trans... Start Learning for Free
 The total thermal resistance of a power transistor and heat sink is 20°C/W. The ambient temperature is 25°C and (TJ)MAX=200°C. If VCE=4V, find the maximum collector current that the transistor can carry without destruction.
  • a)
    3.67A
  • b)
    7.56A
  • c)
    2.19A
  • d)
    4.16A
Correct answer is option 'C'. Can you explain this answer?
Verified Answer
The total thermal resistance of a power transistor and heat sink is 20...
 PD =(TJ-TA)/ H
=200-25/20=8.75W.
Now, VCEIC = 8.75/4=2.19A.
This question is part of UPSC exam. View all Electrical Engineering (EE) courses
Most Upvoted Answer
The total thermal resistance of a power transistor and heat sink is 20...
°C/W. This means that for every watt of power dissipated by the transistor, the temperature of the transistor junction will increase by 20°C above the temperature of the heat sink. For example, if the ambient temperature is 25°C and the power dissipated by the transistor is 5W, then the temperature of the transistor junction will be:

Tj = Ta + (Pd * Rth)
Tj = 25°C + (5W * 20°C/W)
Tj = 125°C

In this case, the temperature of the transistor junction is 125°C, which is well within the maximum operating temperature of most power transistors. However, if the power dissipated by the transistor were to increase, then the temperature of the transistor junction would also increase, potentially leading to thermal runaway and device failure. Therefore, it is important to choose an appropriate heat sink and ensure that the total thermal resistance is low enough to keep the temperature of the transistor junction within safe limits.
Community Answer
The total thermal resistance of a power transistor and heat sink is 20...
Calculate maximum temperature difference from junction to ambient 200-25=175deg
now calculate maximum dissipation allowed considering thermal resistance 175/20=8.5W
Vce -voltage across device while it's carrying current
power dissipation= Vce*Ic
8.5=4*Ic
from which Ic gives answer
Explore Courses for Electrical Engineering (EE) exam

Top Courses for Electrical Engineering (EE)

The total thermal resistance of a power transistor and heat sink is 20°C/W. The ambient temperature is 25°C and (TJ)MAX=200°C. If VCE=4V, find the maximum collector current that the transistor can carry without destruction.a)3.67Ab)7.56Ac)2.19Ad)4.16ACorrect answer is option 'C'. Can you explain this answer?
Question Description
The total thermal resistance of a power transistor and heat sink is 20°C/W. The ambient temperature is 25°C and (TJ)MAX=200°C. If VCE=4V, find the maximum collector current that the transistor can carry without destruction.a)3.67Ab)7.56Ac)2.19Ad)4.16ACorrect answer is option 'C'. Can you explain this answer? for Electrical Engineering (EE) 2024 is part of Electrical Engineering (EE) preparation. The Question and answers have been prepared according to the Electrical Engineering (EE) exam syllabus. Information about The total thermal resistance of a power transistor and heat sink is 20°C/W. The ambient temperature is 25°C and (TJ)MAX=200°C. If VCE=4V, find the maximum collector current that the transistor can carry without destruction.a)3.67Ab)7.56Ac)2.19Ad)4.16ACorrect answer is option 'C'. Can you explain this answer? covers all topics & solutions for Electrical Engineering (EE) 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for The total thermal resistance of a power transistor and heat sink is 20°C/W. The ambient temperature is 25°C and (TJ)MAX=200°C. If VCE=4V, find the maximum collector current that the transistor can carry without destruction.a)3.67Ab)7.56Ac)2.19Ad)4.16ACorrect answer is option 'C'. Can you explain this answer?.
Solutions for The total thermal resistance of a power transistor and heat sink is 20°C/W. The ambient temperature is 25°C and (TJ)MAX=200°C. If VCE=4V, find the maximum collector current that the transistor can carry without destruction.a)3.67Ab)7.56Ac)2.19Ad)4.16ACorrect answer is option 'C'. Can you explain this answer? in English & in Hindi are available as part of our courses for Electrical Engineering (EE). Download more important topics, notes, lectures and mock test series for Electrical Engineering (EE) Exam by signing up for free.
Here you can find the meaning of The total thermal resistance of a power transistor and heat sink is 20°C/W. The ambient temperature is 25°C and (TJ)MAX=200°C. If VCE=4V, find the maximum collector current that the transistor can carry without destruction.a)3.67Ab)7.56Ac)2.19Ad)4.16ACorrect answer is option 'C'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of The total thermal resistance of a power transistor and heat sink is 20°C/W. The ambient temperature is 25°C and (TJ)MAX=200°C. If VCE=4V, find the maximum collector current that the transistor can carry without destruction.a)3.67Ab)7.56Ac)2.19Ad)4.16ACorrect answer is option 'C'. Can you explain this answer?, a detailed solution for The total thermal resistance of a power transistor and heat sink is 20°C/W. The ambient temperature is 25°C and (TJ)MAX=200°C. If VCE=4V, find the maximum collector current that the transistor can carry without destruction.a)3.67Ab)7.56Ac)2.19Ad)4.16ACorrect answer is option 'C'. Can you explain this answer? has been provided alongside types of The total thermal resistance of a power transistor and heat sink is 20°C/W. The ambient temperature is 25°C and (TJ)MAX=200°C. If VCE=4V, find the maximum collector current that the transistor can carry without destruction.a)3.67Ab)7.56Ac)2.19Ad)4.16ACorrect answer is option 'C'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice The total thermal resistance of a power transistor and heat sink is 20°C/W. The ambient temperature is 25°C and (TJ)MAX=200°C. If VCE=4V, find the maximum collector current that the transistor can carry without destruction.a)3.67Ab)7.56Ac)2.19Ad)4.16ACorrect answer is option 'C'. Can you explain this answer? tests, examples and also practice Electrical Engineering (EE) tests.
Explore Courses for Electrical Engineering (EE) exam

Top Courses for Electrical Engineering (EE)

Explore Courses
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev