Question

Explain the characteristics of a p-n junction diode that makes it suitable for its use as a rectifier.

Hint:

The key property of a p-n junction diode that makes it a good rectifier is its ability to only allow current to flow in one direction when forward biased and block current when reverse biased.

Answer 1

Step 1: A p-n junction diode has two main characteristics that make it suitable for use as a rectifier:
Unidirectional Current Flow: When forward biased, the diode allows current to flow easily through it, while when reverse biased, it blocks the current almost completely. This ability to conduct current in only one direction makes the p-n junction diode ideal for converting alternating current (AC) to direct current (DC).
Threshold Voltage: A diode requires a minimum voltage (called the "threshold" or "cut-in" voltage, typically 0.7 V for silicon diodes) to allow current to pass through when forward biased. Below this voltage, the diode does not conduct, which helps in blocking the reverse current.
Step 2: Due to these characteristics, the p-n junction diode can be used in rectifiers to convert AC into DC, as it only allows the current to pass in one direction, thus removing the negative half of the AC signal.