Question

Draw circuit arrangement for studying V-I characteristics of a p-n junction diode.
(b) Show the shape of the characteristics of a diode.
(c) Mention two information that you can get from these characteristics.

Hint:

The diode's V-I characteristics are crucial for understanding how it behaves in circuits, such as in rectifiers or as a switching element.

Answer 1

- Circuit Arrangement for Studying V-I Characteristics of a p-n Junction Diode: The circuit consists of a power supply connected in series with the p-n junction diode and a variable resistor. A voltmeter is connected across the diode to measure the voltage, and an ammeter is connected in series to measure the current.  

- Shape of the Characteristics of a Diode: The V-I characteristics of a diode show a sharp increase in current once the forward voltage exceeds a certain threshold (approximately 0.7V for silicon). In reverse bias, the current remains very small until breakdown occurs at a high reverse voltage.

 - Two Information from the Characteristics: 1. The threshold voltage (or cut-off voltage) at which the diode starts to conduct in the forward direction. 2. The reverse saturation current, which is the small current that flows when the diode is reverse biased and no significant conduction occurs. Thus, the V-I characteristics provide information about the diode's forward threshold and its behavior under reverse bias.