Concept:In a center-tapped rectifier, the full secondary winding voltage appears across the non-conducting diode, requiring a \( \text{PIV} = 2V_m \). In a bridge rectifier, the reverse voltage is shared, requiring only \( \text{PIV} = V_m \).
Formula:$$\text{PIV}_{\text{center-tap}} = 2V_m \quad \text{vs} \quad \text{PIV}_{\text{bridge}} = V_m$$
Solution:- Because each diode in a center-tapped circuit must withstand \( 2V_m \) in reverse bias, higher-voltage diodes are required.
- In a bridge rectifier, each diode only experiences \( V_m \) in reverse bias, allowing the use of diodes with lower breakdown ratings.
Why other options are incorrect:- Option A: Both circuits share the same ripple frequency (\( 2f_{\text{in}} \)).
- Option B: Both circuits share the same theoretical maximum efficiency (\( 81.2\% \)).
- Option D: Bridge rectifiers conduct during both positive and negative half-cycles.
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