Concept:A positive clamper uses a diode, capacitor, and resistor to add a positive DC offset to an AC input signal, shifting the entire waveform upward so that its negative peaks sit at a specified DC reference voltage (typically 0 V).
Formula:$$V_{\text{out}}(t) = V_{\text{in}}(t) + V_m \implies V_{\text{out,min}} = 0\text{ V}, \quad V_{\text{out,max}} = +2V_m$$
Solution:- During the initial negative peak, the diode conducts and charges the series capacitor to \( V_m \).
- On subsequent cycles, the charged capacitor acts as a series DC battery of value \( +V_m \), shifting the waveform upward.
- The peak-to-peak amplitude (\( 2V_m \)) is preserved, but the entire signal is shifted into the positive voltage domain.
Why other options are incorrect:- Option B: Clipping is performed by clipper circuits, not clampers.
- Option C: Frequency doubling occurs in full-wave rectifiers, not clampers.
- Option D: Sine-to-triangle conversion is performed by integrator circuits.
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