Name: Energy Band Gap
Uploaded: 2019-07-19
Duration: 5 min 21 s
Description: We know that certain materials conduct electricity whereas some don’t. Has it got anything to do with their energy bandgap? Let’s find out in this video.

Question

Draw the voltage current characteristics of a

p n

-junction and compare it with characteristic of resistor.

Accepted Answer

The V-I characteristics of p-n junction diode represents the relation between current and voltage and the variations in current with respect to current is shown below;

Here, the X-axis represents the voltage or potential and the Y-axis represents the current in the p-n junction diode.

Now, when the p-n junction diode is reverse biased, the p-type of the semiconductor diode is connected to the negative terminal of the battery and the n-type of the semiconductor diode is connected to the positive terminal of the battery. Hence, the holes in the p-type of the semiconductor will be attracted by the negative terminal of the battery.

Also, the electrons in the n-type of the semiconductor will be attracted to the positive terminal of the battery. This results in barrier potential and hence, results in the increase of the depletion layer. As a result of this, the minority charge carrier will get drifted across the junction and result in the production of a small current.

Now, at the normal temperature, the current will be very low. Also, the applied voltage will provide very little change in the current which is almost negligible. Therefore, we can say that the current under reverse biased condition will be almost independent of the applied voltage.

For a fixed resistor, the voltage is directly proportional to the current. Doubling the amount of energy into the resistor results in a current twice as fast through the resistor. This relationship is called Ohm's Law and is true because the resistance of the resistor is fixed (because the temperature does not change).

Draw the voltage current characteristics of a $p n$ -junction and compare it with characteristic of resistor.

Important Questions on Electronic Devices

Learn and Prepare for any exam you want !

Draw the voltage current characteristics of a pn -junction and compare it with characteristic of resistor.

Important Questions on Electronic Devices

Learn and Prepare for any exam you want !

Draw the voltage current characteristics of a $p n$ -junction and compare it with characteristic of resistor.