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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?

Daniele Tampieri
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Alessio Caligiuri
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  • Not necessarily. *Avalanche* diodes are fully specified here (what's marketed as *Zener* diodes above about 6 V).. – greybeard Apr 13 '23 at 14:32
  • ok; what about diodes that are not specified as avalanche diodes? – Alessio Caligiuri Apr 13 '23 at 14:34
  • Maybe provide an example. I mean, there might be one diode per hundred types that will suffer badly in reverse breakdown and you should not expect someone to uncover that one for you. You might get lucky of course. – Andy aka Apr 13 '23 at 14:38
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    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. – Christianidis Vasileios Apr 13 '23 at 14:43
  • Ok, thanks for your replies. What about Schottky diodes? – Alessio Caligiuri Apr 13 '23 at 15:04
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    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. – Tim Williams Apr 13 '23 at 15:21
  • If your condition is specified in the datasheet or you can get the manufacturer to sign up for it you're fine. If it's not and you can't, you might or might not be OK, no guarantees. – John D Apr 13 '23 at 15:46
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    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. – Verbal Kint Apr 13 '23 at 18:36
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    @AlessioCaligiuri Zener breakdown is generally *not* destructive. But avalanche breakdown very often is. There's an easy-to-read discussion [here](https://www.circuitstoday.com/pn-junction-breakdown-characteristics). – periblepsis Apr 13 '23 at 21:40

1 Answers1

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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.

Voltage Spike
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