Concept:Peak Inverse Voltage (PIV) is the maximum reverse bias voltage that appears across a non-conducting diode during the AC cycle. The diode must have a breakdown voltage greater than this PIV to prevent junction breakdown.
Formula:$$\text{PIV (Half-Wave)} = V_m$$
$$\text{PIV (Full-Wave Bridge)} = V_m$$
$$\text{PIV (Full-Wave Center-Tap)} = 2V_m$$
Solution:- When biased in reverse, the junction must withstand the peak reverse voltage of the waveform.
- PIV is the critical parameter that specifies the maximum safe reverse voltage before electrical breakdown occurs.
Why other options are incorrect:- Option A: Forward voltage drop during conduction is typically only \(0.7\text{ V}\), not the PIV.
- Option C: The voltage required to initiate forward conduction is the knee or threshold voltage (\(V_{\text{knee}}\)).
- Option D: PIV is a peak specification on the diode, not the RMS voltage of the AC supply.
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