Generic selectors
Exact matches only
Search in title
Search in content
Search in posts
Search in pages
Filter by Categories
nmims post
Objective Type Set
Online MCQ Assignment
Question Solution
Solved Question
Uncategorized

1. Find the voltage across the resistor R if VA = -3V and VB = -5V. Use ideal diode model assumption.
analog-circuits-questions-answers-ideal-diode-model-1-q10
a) 0V
b) -3V
c) -5V
d) -4V

View Answer

Answer: a [Reason:] 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 both diode is in reverse bias mode current through diode is zero.

2. Find current I if voltage V = 5V, VB = 2V, R1 & R2 = 2K. Use ideal diode model assumption.
analog-circuits-interview-questions-answers-freshers-q2
a) 1.5mA
b) 1.375mA
c) 2mA
d) 3mA

View Answer

Answer: d [Reason:] 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. 4V forward biases the diode while 2V is reverse bias to the diode. So voltage across R1 is V-VB. That is 3V. Therefore, current through R1 = 3V/2k = 1.5mA. Current through R2 = 3/2K = 2.5mA. Therefore, total current I = 1.5+1.5 = 3mA.

3. Find current I if V = 5V and -5V when VB = 2V, R1 = 2K, R2 = 4K respectively are
analog-circuits-interview-questions-answers-freshers-q3
a) 0A and 1.3mA
b) 1.231mA and 0.33mA
c) 3.25mA and 0A
d) 1.58mA and 0A

View Answer

Answer: c [Reason:] 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. V is forward biasing and VB is reverse biasing to diode. Current through resistor R1 = V/2k = 2.5mA. Current through resistor R2 = (V – VB ) /4k = 0.75mA. So total current is 3.25mA. At V = -5V, diode is reverse bias So the current is zero.

4. The output voltage V if Vin = 3V, R=5K, VB = 2V is
analog-circuits-interview-questions-answers-freshers-q4
a) 1V
b) 4V
c) 5V
d) 2.5V

View Answer

Answer: a [Reason:] 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. Vin reverse biases the diode and VB so total voltage is Vin – VB.

5. In the circuit below VB = 2V, Vin = 5V. The voltage V across resistor R is
analog-circuits-interview-questions-answers-freshers-q5
a) 5V
b) 2V
c) 3V
d) 7V

View Answer

Answer: b [Reason:] 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 Vin reverse biases the diode it won’t be shown in resistor R. So only VB appears.

6. In the circuit Vin = 4V, VB = 3V, R = 5K. The voltage across diode V is
analog-circuits-interview-questions-answers-freshers-q6
a) 1V
b) 4V
c) 3V
d) 7V

View Answer

Answer: a [Reason:] 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 Vin reverse biases the diode and VB forward biases the diode So total voltage across diode is Vin-VB.

7. In the circuit below Vin = 4V, R = 2K and VB = 2V. In these conditions the voltage across diode V is
analog-circuits-interview-questions-answers-freshers-q7
a) -4V
b) -2V
c) 2V
d) 0V

View Answer

Answer: d [Reason:] 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 net voltage Vin – VB = 2V forward biases the diode voltage across diode is zero.

8. In the circuit shown in below I = 2mA, VB = 2V and R = 2K. The voltage V will be
analog-circuits-interview-questions-answers-freshers-q8
a) 0V
b) 2V
c) 4V
d) 1V

View Answer

Answer: b [Reason:] 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 I is forward bias to diode resistor R has no relevance so output voltage is VB.

9. In the circuit shown in below I = 2mA, VB = 2V and R = 2K. The voltage V will be
analog-circuits-interview-questions-answers-freshers-q9
a) 2V
b) 3V
c) 6V
d) 5V

View Answer

Answer: c [Reason:] 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 biased by the current I, Voltage across R = 2mA x 2k = 4V. So total voltage will be 2+4=6V.

10. For circuit shown below Vin = 3V, R1 = 6K, R2 = 2K. The voltage V will be
analog-circuits-interview-questions-answers-freshers-q10
a) 3V
b) 0.75V
c) 1V
d) 1.134V

View Answer

Answer: a [Reason:] 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 entire voltage will appear across R2.