250+ TOP MCQs on Ideal Diode Model and Answers

Analog Circuits Multiple Choice Questions on “Ideal Diode Model – 1”.

1. In ideal diode model diode in forward bias is considered as a ___________
A. Resistor
B. Perfect conductor
C. Perfect insulator
D. Capacitor

Answer: B
Clarification: In ideal diode model the diode is considered as a perfect conductor in forward bias and perfect insulator in reverse bias. That is voltage drop at forward bias is zero and current through the diode at reverse bias is zero.

2. In ideal diode model diode in reverse bias is considered as a ___________
A. Resistor
B. Perfect conductor
C. Perfect insulator
D. Capacitor

Answer: C
Clarification: In ideal diode model the diode is considered as a perfect conductor in forward bias and perfect insulator in reverse bias. That is voltage drop at forward bias is zero and current through the diode at reverse bias is zero.

3. Voltage drop produced by a diode at forward bias in ideal diode model is equal to ___________
A. 0.7V
B. 0.3V
C. 1V
D. 0V

Answer: D
Clarification: In ideal diode model the diode is considered as a perfect conductor in forward bias and perfect insulator in reverse bias. That is voltage drop at forward bias is zero and current through the diode at reverse bias is zero.

4. The current I through the circuit if we consider diode in ideal diode model.

A. 3mA
B. 3A
C. 1A
D. 0.4mA

Answer: A
Clarification: In ideal diode model the diode is considered as a perfect conductor in forward bias and perfect insulator in reverse bias. That is voltage drop at forward bias is zero and current through the diode at reverse bias is zero. Since diode is forward biased current
I = (3V/1K) = 3mA.

5. The voltage VOUT across the ideal diode if VIN is-5V and resistance R1=10KΩ is ___________

A. -5V
B. 0V
C. -2.5V
D. 2.5V

Answer: A
Clarification: In ideal diode model the diode is considered as a perfect conductor in forward bias and perfect insulator in reverse bias. That is voltage drop at forward bias is zero and current through the diode at reverse bias is zero. Since diode is reverse bias no current flows through the circuit so entire voltage appears on diode.

6. The current I through the circuit I if voltage v = -3V is _______________

A. 0A
B. 3A
C. 1.5A
D. 6A

Answer: A
Clarification: In ideal diode model the diode is considered as a perfect conductor in forward bias and perfect insulator in reverse bias. That is voltage drop at forward bias is zero and current through the diode at reverse bias is zero. Since diode is reverse bias no current will flow through the circuit.

7. If current source I produces a current of 1mA and resistance R=3kΩ, then what is the voltage across the resistor given that diode is ideal?

A. 0V
B. 1V
C. 3V
D. 1.5V

Answer: A
Clarification: In ideal diode model the diode is considered as a perfect conductor in forward bias and perfect insulator in reverse bias. That is voltage drop at forward bias is zero and current through the diode at reverse bias is zero.
Since current forward biases the diode it acts as a conductor so current through resistor is zero so voltage is zero. Therefore, voltage across resistor is zero.

8. If resistance R₁ is 10KΩ, V₂ = 2V, V₁ = 3V and the diode is ideal, then the current I through the circuit will be ___________

A. 0.3mA
B. 0.6mA
C. 0.7mA
D. 0.1mA

Answer: D
Clarification: In ideal diode model the diode is considered as a perfect conductor in forward bias and perfect insulator in reverse bias. That is voltage drop at forward bias is zero and current through the diode at reverse bias is zero.
Since the diode is in reverse bias, it can be considered open and no current flows through it. Then effective voltage becomes 3-2 = 1V so current is 1/10K = 0.1mA.

9. If resistance R₁ is 10K, V₂ = – 2V, V₁ = 3V and the diode is ideal then the current I through the circuit will be _________

A. 0.2mA
B. 0A
C. 0.5mA
D. 0.3mA

Answer: D
Clarification: In ideal diode model the diode is considered as a perfect conductor in forward bias and perfect insulator in reverse bias. That is voltage drop at forward bias is zero and current through the diode at reverse bias is zero.
The voltage V₂ forward biases the diode so in effect V₂ Vanishes. Also V₁ is in reverse bias to the diode so it will not pass through diode. Therefore, effective current will be
(3V/10K) = 0.3mA.

10. What will be the voltage Vout if V_A = 3V and V_B = -5V and the diodes are ideal?

A. 5V
B. 3V
C. 2V
D. 0V

Answer: B
Clarification: In ideal diode model the diode is considered as a perfect conductor in forward bias and perfect insulator in reverse bias. That is voltage drop at forward bias is zero and current through the diode at reverse bias is zero. Since first diode is in forward bias and second diode is in reverse bias. So Only first diode will pass the current.