In a PN junction diode, forward bias occurs when which of the following is true?

In a PN junction diode, forward bias occurs when which of the following is true?

• A. P-type receives a negative charge and N-type receives a positive charge
• B. P-type receives a positive charge and N-type receives a negative charge
• C. Both P and N receive positive charges
• D. Both P and N receive negative charges

Answer: (B)

Forward bias lowers the PN junction’s barrier by applying a positive voltage to the P-type side and a negative voltage to the N-type side. This reduces the depletion region, allowing holes from the P side and electrons from the N side to cross the junction, so conventional current flows from P to N. If the P side were made negative and the N side positive, the depletion region widens and current is blocked (reverse bias).

Forward bias lowers the PN junction’s barrier by applying a positive voltage to the P-type side and a negative voltage to the N-type side. This reduces the depletion region, allowing holes from the P side and electrons from the N side to cross the junction, so conventional current flows from P to N. If the P side were made negative and the N side positive, the depletion region widens and current is blocked (reverse bias).