A. When the forward bias voltage across a p-n junction diode increases above a certain threshold voltage, the diode current increases significantly.
B. This current is called reverse saturation current.
Choose the correct answer from the options given below :
To determine the correctness of the given statements, let's analyze each one based on the fundamental concepts of p-n junction diodes:
- Statement A: "When the forward bias voltage across a p-n junction diode increases above a certain threshold voltage, the diode current increases significantly."
- Explanation: In a p-n junction diode, when forward bias voltage is applied, it reduces the barrier potential, allowing charge carriers (electrons and holes) to cross the junction easily. Once the applied voltage exceeds the threshold or knee voltage (usually around 0.7V for silicon diodes, and 0.3V for germanium diodes), the diode starts conducting, and the current increases exponentially. This is a well-understood behavior of diodes.
- Conclusion: Statement A is correct.
- Statement B: "This current is called reverse saturation current."
- Explanation: Reverse saturation current is the small constant current that flows through the diode when it is reverse biased, due to minority carrier drift. In contrast, the significant current that flows when a p-n junction diode is forward biased above the threshold voltage is simply the forward current, not the reverse saturation current.
- Conclusion: Statement B is incorrect, as it mislabels the type of current as reverse saturation current.
Conclusion: After analyzing both statements, we can conclude that Statement A is true but Statement B is false. Therefore, the correct answer is the option stating, "Statement A is true but Statement B is false."
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