Semiconductor Electronics · Question 107

From the following diode circuits, which diode is in forward biased condition?

1. [figure]
2. [figure]
3. [figure]
4. [figure]

Answer

(1) [figure]

Solution

∵ A p-n junction diode is forward biased when its p-side (the triangle end) is at a higher potential than its n-side (the bar end).

(1) p-side 0 V > n-side -2 V ⇒ forward biased

(2) p-side 0 V < n-side 2 V ⇒ reverse biased

(3) p-side -5 V < n-side -2 V ⇒ reverse biased

(4) p-side 5 V < n-side 12 V ⇒ reverse biased

Answer: (1)