Explain breakdown voltage and PIV. How does temperature affect diode I-V characteristics in forward and reverse bias?

3(a) (i)

• Breakdown voltage is the reverse voltage at which a diode begins to conduct a large current due to avalanche or Zener breakdown, potentially damaging the diode if not current-limited.
• Peak Inverse Voltage (PIV) is the maximum reverse voltage a diode can withstand without breaking down, specifying its safe operating limit in reverse bias.

3(a) (ii)
When temperature increases, the I-V characteristics of a diode change:

• In forward bias, the forward voltage required to achieve a certain current decreases. This means the I-V curve shifts to the left, indicating the diode turns on at a lower voltage.
• In reverse bias, the reverse saturation current ($I_S$) increases significantly with temperature. This leads to a higher leakage current in the reverse direction. The breakdown voltage generally decreases slightly with increasing temperature for Zener diodes, while for avalanche diodes, it can increase.