Question

Consider two diodes, A is step graded, B is linear graded. Find the ratio of the capacitance of A to B, when the applied voltage in reverse bias is 64V.

(a) 0.2

(b) 2

(c) 0.5

(d) 5

The question was asked during an interview.

I need to ask this question from Transition Capacitance in chapter Diode Circuit of Analog Circuits

Answer 1

Correct option is (d) 5

The explanation: In A, CA ∝ \(\frac{1}{\sqrt{V}}\)

CB ∝ \(\frac{1}{\sqrt[3]{V}}\)

\(\frac{C_A}{C_B} = \frac{4}{8} = \frac{1}{2}\) = 0.5.