A limiter circuit is also known as a clipper circuit.
A clipper is a device that removes either the positive half (top half) or negative half (bottom half), or both positive and negative halves of the input AC signal.
The clipping (removal) of the input AC signal is done in such a way that the remaining part of the input AC signal will not be distorted
In the below circuit diagram, the positive half cycles are removed by using the series positive clipper.
2. Which of the following circuits is used to add a DC offset to the waveform?
Clamper
Clipper
Amplifier
Rectifier
Answer.1. Clamper
A Clamper circuit can be defined as a circuit that consists of a diode, a resistor, and a capacitor that shifts the waveform to the desired DC level without changing the actual appearance of the applied signal.
Clamper circuits is used to add a DC offset to the waveform.
In order to maintain the time period of the waveform, the tau must be greater than, half the time period (discharging time of the capacitor should be slow)
3. Circuit used to shift the DC level of the input signal is:
Clamper
Rectifier
Amplifier
Clipper
Answer.1. Clamper
A Clamper circuit can be defined as a circuit that consists of a diode, a resistor, and a capacitor that shifts the waveform to the desired DC level without changing the actual appearance of the applied signal.
In order to maintain the time period of the waveform, the time constant (RC) must be greater than half the time period (discharging time of the capacitor should be slow).
4. A clamper circuit
Adds or subtracts a dc voltage to or from a waveform
Does not change the shape of the waveform
Both 1 and 2
None of the above
Answer.3. Both 1 and 2
A clamper is an electronic circuit that changes the DC level of a signal to the desired level without changing the shape of the applied signal.
The Clamper circuit moves the whole signal up or down to set either the positive feedback or negative feedback of the signal at the desired level.
5. The primary function of a clamper circuit is
Suppress variations in signal voltage
Raise the positive cycle of the signal
Lower the negative cycle of the signal
Introduce a DC level to an ac signal
Answer.4. Introduce a DC level to an ac signal
A Clamper Circuit is a circuit that adds a DC level to an AC signal.
The shape of the output waveform does not change in Clamper circuits.
Since the clamper circuit adjusts the DC level of the waveform as shown in the following figure, it is called DC restorer.
6. For the Clamp circuit one must _____
add DC signal with DC
add AC signal with DC
add AC signal with AC
subtract AC from DC
Answer.2. add AC signal with DC
A Clamper Circuit is a circuit that adds a DC level to an AC signal.
Since the clamper circuit adjusts the DC level of the waveform as shown in the following figure, it is called DC restorer.
7. In the circuit shown below, the diode is ideal and the input is Vi = 4 + 10 sin ωt.
V0max = 1 V
V0 min = -9V
V0avg = -19 V
The maximum voltage across the capacitor will be 13 V
Answer.4.
The capacitor is getting charged, and applying KVL around the loop, we can write:
Vi – Vc – 1 = 0
Vc = Vi – 1
Vc will charge to the maximum voltage possible, i.e.
Vc max = Vi max – 1
Vc max = (4 + 10) – 1
Vc max = 14 – 1 = 13 V
Once Vc becomes 13 V, the current flow in the circuit becomes zero & Vc remains constant at 13 V as there is no discharging path given in the circuit.
8. Which circuit is used for obtaining desired output waveform in the operational amplifier?
A. Clipper
B. Clamper
C. Peak amplifier
D. Sample and hold
Answer: A
In an op-amp clipper circuit, a rectifier diode is used to clip off certain portions of the input signal to obtain a designed output waveform.
9. The clipping level in op-amp is determined by
A. AC supply voltage
B. Control voltage
C. Reference voltage
D. Input voltage
Answer: C
The clipping level is determined by the reference voltage which should be less than the input voltage range of an op-amp.
10. In a positive clipper, the diode conducts when
A. Vinref
B. Vin = Vref
C. Vin > Vref
D. None of the mentioned
Answer: B
In a positive clipper, the diode conducts until Vin = Vref (during the positive half cycle of the input), because when Vinref, the voltage (Vref) at the negative input is higher than that at the positive input.