This set of Analog Electronic Circuits Multiple Choice Questions & Answers (MCQs) focuses on “Characteristic Equation of Diode-2.

1. Find voltage VOUT if the reverse saturation current of the diode is 1.1×10^{-8}A, the cut-in voltage of diode is 0.6V and assume the temperature as 25^{o}C.

a) 0.235V

b) 0.3148V

c) 0.456V

d) 0.126V

2. The current Ix in the circuit is 1mA then find the voltage across diode D1. The resistance R1 is 1KΩ. Assume the reverse saturation current is 10^{-9}A. Voltage across resistor in this condition was 0.4V. Take V_{T} of diode as 0.026V.

a) 2.3mA

b) 3.2mA

c) 5.2mA

d) 4.6mA

3. Find the current I if both diodes are identical. Voltage V = 0.8V and let the reverse saturation current be 10^{-9}A.

a) 4.8mA

b) 3.2mA

c) 2.5mA

d) 7mA

4. Find the current Ix if the voltage across the diode is 0.5V. The reverse saturation current of diode 10^{-11}A, the cut-in voltage of diode is 0.6V. Assume that the temperature at which diode operates is 25°C. The resistance R1=2KΩ.

a) 3.97mA

b) 4.51mA

c) 2.45mA

d) 3.05mA

5. If the temperature increases 10°C, the ratio of final reverse saturation current to initial reverse saturation current is _______

a) 1

b) 2

c) 1.5

d) 3

6. How much times reverse saturation current will increase if temperature increases 15^{o}C?

a) 2.52

b) 4.62

c) 4.12

d) 2.82

7. If the current I is 2mA then find the temperature at which diode operates. The cut-in voltage of diode is 0.6V. The reverse saturation current of diode is 10^{-9}A. Resistance R is 1.3KΩ.

a) 45.85°C

b) 50.47°C

c) 60.26°C

d) 56.89°C

8. The reverse saturation current of a diode at 25°C is 1.5 x 10^{-9}A. What will be the reverse current at temperature 30°C?

a) 3 x 10^{-9}A

b) 2 x 10^{-9}A

c) 2.12 x 10^{-9}A

d) 1.5 x 10^{-9}A

9. The input voltage V1 of the circuit the circuit is 2V and resistor has a resistance of 1KΩ. The cut-in voltage of the silicon diode is 0.7V and the reverse saturation current is 10^{-8}A. The temperature at which diode operates is 30°C. The voltage across resistor when diode starts conducting is _________________

a) 0.7V

b) 1.3V

c) 0.306V

d) 1.7V

10. If V1 is 5V and resistance R_{1} is 5KΩ and the cut-in voltage of the diode is 0.7V, what will be the voltage V_{out} across the diode? Take reverse saturation current as 10^{-8}A and operating temperature as 25°C.

a) 0V

b) -4.5V

c) -5V

d) -3.2V