Exam-style question
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In a photodiode, what is the relationship between the reverse bias voltage and the photocurrent?.
- A.The photocurrent decreases with increasing reverse bias.
- B.The photocurrent increases with increasing reverse bias.
- C.The photocurrent is independent of reverse bias.
- D.The photocurrent fluctuates with reverse bias.
Model answer
What a good answer should say
- The photocurrent decreases with increasing reverse bias.
Explanation
Why this works
The evidence indicates that increasing reverse bias voltage can lead to a reduction in the photocurrent due to the widening of the depletion region, which limits the number of charge carriers. This implies that there is an optimal reverse bias for maximum photocurrent.
Therefore, we conclude that excessive reverse bias can hinder the performance of photodiodes in sensing applications.
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