Question

The light emitting diode $(LED)$ is

• A. a heavily doped p-n junction with no external bias
• B. a heavily doped p-n junction with reverse bias
• C. a heavily doped p-n junction with forward bias
• D. a lightly doped p-n junction with no external bias

Answer 1

Answer: (C)

a heavily doped p-n junction with forward bias

Answer 2

The light emitting diode $(LED)$ is a heavily doped $p-n$ junction with forward bias. Because it is an important light source used in optical communication and is based on the principle of conversion of biasing electricity into light. It is a specially designed forward-biased $p-n$ junction diode which emits light spontaneously when energised.