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If a diode is operated in breakdown region and if it is used again will it lose its characteristics or work normally?

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Breakdown itself does not damage a diode, if the current is limited. Zener diodes constantly work in this mode.

What is important is that if there is no current limiting, the diode will heat until it would burn, and you'll have a short circuit or open circuit, and it won't work.

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    \$\begingroup\$ Just curious, what actually prevents me from using a "regular" diode as a zener one, given that I'll take care not to burn it with excessive heat? \$\endgroup\$ – whitequark Aug 12 '11 at 18:59
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    \$\begingroup\$ @whitequark, There are several differences. First, Regular diodes generally have much higher breakdown voltages than zener diodes. Next, Regular diodes tend to experience avalanch breakdown. It looks superficially similar to zener breakdown, but it has hysteresis, so current will continue to flow even if you drop below the breakdown voltage (until you reach a lower threshold). The zener breakdown effect has a negative temperature coefficient, while avalanch breakdown has a positive temperature coefficent. \$\endgroup\$ – Kevin Cathcart Aug 12 '11 at 19:50
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    \$\begingroup\$ @whitequark, The next difference is that zenner diodes are specifically constructed such that the breakdown voltage does not vary much with current. Regular diodes tend to exibit more variance. Finally, zenner diodes are constructed such that there will be little variance in breakdown voltage between parts. Regular diodes will likely show greater variance between specimens. \$\endgroup\$ – Kevin Cathcart Aug 12 '11 at 19:55
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    \$\begingroup\$ @Kevin "Zener" diodes above 5.6V break down by avalanche and not because of the actual Zener effect. \$\endgroup\$ – jpc Aug 12 '11 at 21:29
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    \$\begingroup\$ @jpc, true although as you point out those are not really Zener diodes, but avalanche diodes, although product marketing chooses not to make a distinction. Now those with a breakdown voltage of almost exactly 5.6 are rather interesting, because both effects are occurring simultaneously. They really cannot be classified as either zener or avalanche. \$\endgroup\$ – Kevin Cathcart Aug 17 '11 at 12:48
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zener breakdown is different from avalanche breakdown in the sense that zener breakdown occurs in heavily doped diodes where the depletion region is very narrow, therefore a comparatively small reverse voltage is sufficient to start conduction, whereas normal diodes are lightly doped thereby the depletion region is very wide, so a very high reverse voltage is necessary to start conduction. But remember one thing that this conduction in both cases occurs because electrons get highly accelerated and knock off electrons from other atoms therby creating more electron ion pairs

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  • \$\begingroup\$ Okay, but how does this answer what happens after a diode is used in the breakdown region? \$\endgroup\$ – Null Feb 27 '16 at 4:47

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