Physics - Semiconductors Question with Solution | TestHub
I-V characteristics of LED is shown correctly by graph
Options:
Answer:
Solution:
An LED (Light Emitting Diode) is a heavily doped p-n junction diode that operates in forward bias.
In forward bias, the current remains very small until the applied voltage exceeds the threshold (cut-in) voltage of the diode. Beyond this threshold voltage, the forward current increases rapidly with the applied voltage.
This behavior is correctly depicted in graph (b), which shows the forward bias I-V characteristics in the first quadrant.
For context:
- Graph (a) represents a typical p-n junction diode or Zener diode showing both forward and reverse characteristics.
- Graph (c) represents a solar cell (operating in the fourth quadrant).
- Graph (d) represents the magnitude of a photodiode's reverse bias characteristics.
Answer: b
