Concept:A negative clamper adds a negative DC offset to an AC input signal, shifting the entire waveform downward so that its positive peaks sit at a reference DC level (typically 0 V).
Formula:$$V_{\text{out}}(t) = V_{\text{in}}(t) - V_m \implies V_{\text{out,max}} = 0\text{ V}, \quad V_{\text{out,min}} = -2V_m$$
Solution:- During the initial positive peak, the diode conducts and charges the capacitor to \( V_m \) with reverse polarity.
- On subsequent cycles, the capacitor holds this charge, acting as a series DC offset of \( -V_m \).
- This shifts the entire waveform downward while preserving its \( 2V_m \) peak-to-peak amplitude.
Why other options are incorrect:- Option A: Passive clamper circuits do not provide signal amplification.
- Option C: Removing negative half-cycles is the function of a half-wave rectifier or clipper.
- Option D: Clampers shift signal levels; they do not generate radio frequencies.
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