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Take a PN or Schottky diode and apply a reverse bias voltage. Go beyond the absolute maximum reverse voltage (given by the datasheet) and limit the current to a low value, such that \$P = V\cdot I\$ is low enough to not thermally destroy it. In this configuration, is reverse breakdown destructive for PN or Schottky diodes?

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  • \$\begingroup\$ Not necessarily. Avalanche diodes are fully specified here (what's marketed as Zener diodes above about 6 V).. \$\endgroup\$
    – greybeard
    Commented Apr 13, 2023 at 14:32
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    \$\begingroup\$ I also dont think this is a no or yes answer. Provided that you do not exceed the maximum current mentioned in datasheet, reverse breakdown might not damage diodes. BUT, PN diodes are not meant or supposed to used that way. If the manufacturer did not test reverse breakdown and did not provide you with the maximum current you can use on reverse breakdown, then no one guarantees the diode will work as expected. Its all about how the manufacturer tested the part and what they guarantee you. \$\endgroup\$ Commented Apr 13, 2023 at 14:43
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    \$\begingroup\$ I don't know about the breakdown characteristics of a naked schottky junction, but schottky diodes generally have PN guard rings which are designed to avalanche just beyond the rated voltage. Some are indeed rated for avalanche energy, making them ESD safe for example. Other devices may fail destructively, like GaN PN junctions; at least, I haven't seen any that are rated for avalanche, and every blue/white LED I've tested, has failed even at fractional mA bias. \$\endgroup\$ Commented Apr 13, 2023 at 15:21
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    \$\begingroup\$ No, it won't be destructive if you limit the avalanche current: this is the principle of curve tracers used to plot I-V characteristics of diodes in forward and reverse modes. \$\endgroup\$ Commented Apr 13, 2023 at 18:36
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    \$\begingroup\$ @AlessioCaligiuri Zener breakdown is generally not destructive. But avalanche breakdown very often is. There's an easy-to-read discussion here. \$\endgroup\$ Commented Apr 13, 2023 at 21:40

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It will be destructive if you exceed the absolute maximum ratings of the part. The three main things not to exceed would be:

  1. Maximum current

  2. Maximum temperature

  3. Maximum reverse voltage If you do put it in a reverse breakdown configuration, you will probably exceed this rating, the device will probably fail the more current you put through it and you would exceed the current rating the more voltage that is put across the diode. But at this point the manufacturer says don't do it.

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