photodiode

Question

Question

Assume that the total time response of a vacuum photodiode is given by the sum of

the transit time and the RC time constant. (a) Derive an expression for the plate

separation d that minimizes the total response time. Put your answer in terms of the

applied voltage V0, the plate area A, and the load resistor R. (b) Calculate this optimum

plate separation for parallel plates of diameter 2 cm, a voltage 2.5 kV, and a

load resistance 50 _. Repeat for a load resistance 1 k_. (c) Determine the optimized

total response time for the two values of R in part b.

Answer 1

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