If a transistor has a power rating of 1 W and a collector current of 100 mA, what is the maximum allowable collector voltage________________?
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Answer: D. 10V
Explanation
Maximum collector voltage is determined by dividing the maximum power rating by the collector current (1 watt divided by 100 milliamperes equals 10 volts). Power dissipation in a transistor is the product of collector-emitter voltage and collector current under operating conditions. Rearranging the power formula allows engineers to calculate safe voltage limits to prevent thermal overload and device destruction. Semiconductor devices have strict maximum ratings specified by manufacturers to ensure safe and reliable long-term operational performance. Exceeding the maximum power dissipation rating causes excessive internal heating that can permanently damage the junction structure. Safe operating area curves combine voltage, current, and power limits to guide designers in selecting appropriate transistor protection.
One volt is incorrect because dividing one watt by one hundred milliamperes yields ten volts, not one volt. One hundred volts is mathematically incorrect and would drastically overestimate the safe operating voltage for this power rating. Twenty volts is twice the correct calculated value resulting from an error in dividing power by current.
- Subject
- Engineering
- Category
- Electrical Engineering
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- —
- Difficulty
- medium
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