Clampers are electronic circuits that shift a waveform to a different voltage level without changing its appearance. There are two main types: positive clampers shift the input signal in a positive direction above a reference level, while negative clampers shift it in a negative direction below the reference. Clampers work by using diodes and capacitors to either pass or block portions of the input signal depending on its polarity, resulting in the output being shifted to a different DC level from the input but retaining the same AC waveform. They are commonly used in applications like test equipment, radar, sonar, and television receivers.

1. Clampers
Mateen chaudhary

2. clampers

3. clampers
• A network that shifts a waveform to a
different level
• Does not change the appearance of the
applied signal
• Time constant
t=RC

4. Operation of clampers

5. clampers
• Positive clampers
– Shifts its input waveform in a positive direction
– lies above a dc reference voltage
• Negative clampers
– shifts its input waveform in a negative direction
– lies below a dc reference voltage

6. Positive clampers

7. Positive clampers
In ideal case

8. clampers
• Clamping is not perfect since diode drops
0.7V.
Negative peak

9. Working of positive clamper
• Negative half cycle
– Conduct and act as short
circuit and Output v=0
– Capacitor is charged to peak
value and behave like battery
• Positive half cycle
– Does not conduct and act as open circuit
– Output voltage
vo=vm+vm

10. Positive clamper

11. Negative clamper

12. Working of negative clampers
• Positive half cycle
– diode conducts and acts like
a short circuit
– Capacitor is charged to peak
value and behave like battery
Output v=0
• Negative half cycle
– diode is open and output can be found by
applying KVL

13. Negative clamping
• vm-vm-vo =0
• Vo=-2vm

14. Clamping networks

15. Application of clampers
• Test equipment
• Radar systems
• Sonar systems
• Electronic counter measure systems
• Used in TV receivers as a DC restorer