Concept:In a Cockcroft-Walton ladder multiplier, each stage shifts and rectifies an AC swing of \( 2V_m \), so every diode in the cascade experiences a maximum reverse voltage of \( 2V_m \) regardless of the total number of stages.
Formula:$$\text{PIV}_{\text{each diode}} = 2 V_m \quad (\text{constant across all cascaded stages})$$
Solution:- The first clamping diode experiences \( 2V_m \) peak-to-peak.
- All subsequent stages operate between DC rails separated by \( 2V_m \).
- Therefore, every diode in the cascade only needs to withstand \( \text{PIV} = 2V_m \), making high-voltage generation modular and cost-effective.
Why other options are incorrect:- Option A: \( V_m \) is insufficient to withstand the \( 2V_m \) peak-to-peak swing.
- Option C: \( n V_m \) is the total output DC voltage of the stack, not the voltage across an individual diode.
- Option D: Individual diodes do not experience \( 4V_m \).
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