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Suppose an NPN BJT operates with the base-emitter junction forward biased and the base-collector junction reverse biased. Find is, a, and B when ic = 9 mA for is = 0.3 mA.

User Zxcmehran
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Final answer:

The student's question pertains to finding the common base current gain (α) and common emitter current gain (β) for an NPN BJT given that the collector current (Ic) is 9 mA and the reverse saturation current (Is) is 0.3 mA.

Step-by-step explanation:

The student is asking about a bipolar junction transistor (BJT), specifically an NPN transistor, and how to determine the reverse saturation current (Is), the common base current gain (α), and the common emitter current gain (β) given that the collector current (Ic) is 9 mA when the reverse saturation current (Is) is 0.3 mA.

To solve this question, we use the transistor equations: Ic = α * Ie + Is, where Ic is the collector current, α is the common base current gain, Ie is the emitter current, and Is is the saturation current. If we also know that Ie = Ib + Ic (where Ib is the base current), and β (the common emitter current gain) is related to α by the equation β = α / (1 - α), we can determine α and β given Ic and Is values. In this case, as Is has already been given, we only need to find α and subsequently β.

User Andrey Nikolov
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