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What are the typical values of reverse saturation current of a LED? In particular is it possible to have a reverse saturation current of \$10^{-17} A-10^{-18} A\$ for a (red) LED?

For a silicon diode the typical values are \$10^{-9}A-10^{-12} A\$. Do LEDs have much lower reverse saturation currents usually?

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  • \$\begingroup\$ How can you justify your presumptions for LEDs? \$\endgroup\$ – Sunnyskyguy EE75 Mar 3 '17 at 23:06
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The materials used for LEDs have a larger energy gap than silicon so the reverse leakage is usually a few nA or less. The devices are often not tested for that parameter however as it is not important for normal use so the data sheet may show a much higher value

They also typically have a low reverse voltage specification - again this is because in normal use they are only subjected to a few volts of reverse bias (for example in a typical multiplexed arrangement they will see the forward bias of another LED).

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Most LEDs are rated for reverse leakage current at 10uA. Some are rated at 100uA. They are all rated at -5V as the absolute maximum rated voltage.

From reading thousands of LED data sheets, I have never seen any LED spec'd less than 1uA max although this doesn't mean they all perform this way.

I did a spot check at Digikey

  • 100uA max 5mm C503B-RCN-CW0Z0AA1 Cree RED
  • 100uA max 5mm LTL-4223-R1 Lite-ON RED
  • 10 uA max 3mm TLDR4400 Vishay Deep RED

I believe leakage current is related the limited number of minority carriers near the junction but this gets swamped by material impurities and also increases with damage from ESD or overvoltage from my experience.

My supplier specs are 1uA for Red Yellow LEDs AlinGaAs and 10uA for Blue White.

Supplementary info

https://www.digikey.com/en/articles/techzone/2012/apr/structural-defects-undermine-led-luminosity

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  • \$\begingroup\$ It doesn't deserve much effort as the theoretical question is far from reality. \$\endgroup\$ – Sunnyskyguy EE75 Mar 3 '17 at 2:20
  • \$\begingroup\$ Can/will the luminous one who downvoted please justify their position? \$\endgroup\$ – Sunnyskyguy EE75 Mar 3 '17 at 23:05

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