Question

For a diode connected in parallel with a resistor, which is the most likely curren $I$-voltage $V$ characteristic?

• A.
• B.
• C.
• D.

Answer 1

Answer: (A)

When $V$ is negative, diode is in reverse bias and it does not conducts.
So, current-voltage relationship followed from Ohm’s law is, $V=IR$
$\therefore V-I$ graph is straight line.
As $V$ grows in positive region, diode becomes conductive after knee voltage and after that current is approximately,
$I=I_s{e}^{V/n{V}_T}$
where, $I_s=$ saturation current in reverse bias, $V=$ voltage across diode $n$ and $V_T$ are diode constants. So, correct graph