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Analog Circuits Quiz on “Parallel Clipper Circuit with Reference Voltage-2”.
1. What will be the output of the circuit Vout if the voltage V2 is 1V and input to the circuit V is 5sint?
(Use constant voltage drop model for diode and take cut-in voltage as 0.7V)
Answer: B
Clarification: V2 is forward bias to diode. At positive cycle of V diode is reverse biased and output will be the half of input (Since input is divided by two 1k resistors). At negative cycle output will be 0.3 because diode is forward biased.
2. What will be the output of the circuit Vout if the voltage V2 is 1V and input to the circuit V is 5sint?
(Use constant voltage drop model for diode and take cut-in voltage as 0.7V)
Answer: c
Clarification: V2 is reverse bias to diode. When diode is forward biased output will be 1.7V all other time output will be 5sint/2(Since input is divided by two 1k resistors).
3. What will be the output of the circuit Vout if the voltage V2 is 1V and input to the circuit V is 5sint?
(Use constant voltage drop model for diode and take cut-in voltage as 0.7V)
Answer: C
Clarification: V2 is reverse bias to diode. When diode is forward biased output will be 1.7V all other time output will be 5sint/2 (Since input is divided by two 1k resistors, here third resistor is insignificant since diode is not real).
4. What will be the output of the circuit Vout if the voltage V2 is 1V and input to the circuit V is 5sint?
(Use constant voltage drop model for diode and take cut-in voltage as 0.7V)
Answer: d
Clarification: V2 is forward bias to diode. At positive cycle of V diode is reverse biased and output will be the half of input (Since input is divided by two 1k resistors, here third resistor is insignificant since diode is not real). At negative cycle output will be 0.3 because diode is forward biased.
5. What will be the output of the circuit Vout if the voltage V2 is 1V and input to the circuit V is 5sint?
(Use constant voltage drop model for diode and take cut-in voltage as 0.7V)
Clarification: We change the delta resistor network into a star, where each resistance is now 1/3 ohms. Hence the voltage at node is now 5sint x 1/5 = sint. Hence maximum output is only 1V. The node voltage needs to be less than 0.3V for diode to conduct. That moment, the output is zero. For voltage above 0.3V, the output is obtained.
6. What will be the output of the circuit Vout if the voltage V2 is 0.1V and input to the circuit V is 5sint?
(Use constant voltage drop model for diode and take cut-in voltage as 0.7V)
Clarification: We must solve this problem using star- delta conversion. If not this will be difficult to solve.
After conversion circuit diagram will be as follows
For positive half cycle of V, diode will be forward biased if V is greater than 2.51V (that is we need 1.7V at output and therefore input must be 0.8×1.66/0.33 = 4V.
For negative half cycle output follows input with compression of 0.198.
Therefore, minimum voltage will be -5×0.198 = -0.99V.
7. What will be the output of the circuit Vout if the voltage V2 is 1V and input to the circuit V is 5sint?
(Use constant voltage drop model for diode and take cut-in voltage as 0.7V)
Answer: C
Clarification: Since V2 is reverse bias to diode, the peak of output will be 1.7V. It is because after 1.7V diode becomes forward bias and voltage drop across diode becomes a constant. For V<1.7 output follows input because diode is in reverse bias mode.
8. What will be the output of the circuit Vout if the voltage V2 is 1V and input to the circuit V is 5sint?
(Use constant voltage drop model for diode and take cut-in voltage as 0.7V)
Answer: B
Clarification: Since V2 is forward bias to diode, the peak of output will be 5V. It is because after 0.3V diode becomes reverse bias and output follows input. For V<0.3 voltage drop across diode becomes a constant because diode is in forward bias mode and output will be 0.3V (1-0.7V).
9. What will be the output of the circuit Vout if the voltage V1 is 1V, V2 is 1V and input to the circuit V is 5sint?
(Use constant voltage drop model for diode and take cut-in voltage as 0.7V)
Answer: D
Clarification: Since V2 is reverse bias to diode, the peak of output will be 1.7V. It is because after 1.7V diode becomes forward bias and voltage drop across diode becomes a constant. For V<1.7 output follows input because diode is in reverse bias mode. Input will be 5sint-1. So minimum output voltage is -6V.
10. What will be the output of the circuit Vout if the voltage V1 is 1V, V2 is 1V and input to the circuit V is 5sint?
(Use constant voltage drop model for diode and take cut-in voltage as 0.7V)
Answer: C
Clarification: Since V2 is forward bias to diode, the peak of output will be 3V (5-1-1). It is because after 1.3V diode becomes reverse bias and output follows input (5sint-2). For V<1.3V voltage drop across diode becomes a constant because diode is in forward bias mode and output will be 0.7V.