What is the function of a crowbar circuit in protecting electronic systems_____________?
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Answer: A. voltage sensitive load from excessive dc power supply output voltages
Explanation
A crowbar circuit rapidly short-circuits power supply outputs to protect voltage-sensitive loads from overvoltage. Excessive DC supply voltages can destroy sensitive downstream electronic components instantly. The crowbar action triggers a fast thyristor to clamp the voltage to near zero volts. Crowbar protection gets its name because its action resembles dropping a heavy metal crowbar across terminals. Voltage-sensitive loads include microprocessors and sensitive analog integrated circuits. Power supply failures can cause catastrophic overvoltage conditions without crowbar protection.
Critical computer servers and aerospace electronics utilize crowbar circuits for ultimate overvoltage safety. Fast-acting protection prevents expensive hardware damage during power supply regulator failures. Engineers design crowbar trigger thresholds just above normal maximum operating DC voltages. Current sensitive loads require current-limiting fuses rather than voltage-shorting crowbar circuits. Protecting against AC supply voltages involves different surge suppression devices than DC crowbars. Current sensitive AC loads use circuit breakers rather than DC voltage crowbar protection.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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