An SCR gate-cathode characteristic follows a line of slope 130. Given a trigger source voltage of 15 V and 0.5 W allowable gate dissipation, calculate the required gate-source resistance_____?
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Answer: A. 111.9 Ω.
Explanation
Using the given slope and dissipation limit equations yields the required gate resistance. Calculations involving trigger source voltage and allowable power dissipation determine exact values. The mathematical evaluation results in a gate-source resistance of approximately 111.9 ohms. Silicon controlled rectifiers require specific gate trigger voltages and currents to turn on. Gate power dissipation must remain below maximum manufacturer ratings to prevent thermal damage. Ohm law relates voltage, current, and resistance in electrical and electronic circuits.
Designing reliable trigger circuits is essential for precise thyristor firing control. Engineers calculate exact resistor values to protect sensitive semiconductor gate junctions. Power electronic converters depend on accurate gate driver circuitry for stable operation. Option B underestimates the required resistance value by a factor of ten. Option C provides an incorrect calculation result derived from erroneous formula inputs. Option D represents a rounding error that fails to match precise mathematical derivations.
- Subject
- Engineering
- Category
- Electrical Engineering
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- —
- Difficulty
- medium
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