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How will temperature affect the output of a semiconductor diode?

Kevin Vermeer
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Cell-o
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  • Many books could be written and armies of PhD students employed to investigate this problem as stated, and there would still be more to learn. What do you want to know about the effects of temperature on a diode? This question is overly broad, and could be closed. – Kevin Vermeer May 16 '11 at 18:39
  • Also, I've removed your "Hi" and "Thanks" lines per the site guidelines. They are considered good manners in some contexts, but the Stack Exchange network is not one of these places: Here, they're noise and distract from the asking and answering of questions. Please don't do this in the future! Thanks! – Kevin Vermeer May 16 '11 at 18:41
  • Reverse leakage current will also increase - many of the answers to [this question](http://electronics.stackexchange.com/questions/13873/why-exactly-do-chips-start-malfunctioning-once-they-overheat/13903#13903) will also apply to what you have asked here – SimonBarker May 05 '11 at 09:07

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The forward voltage of a Si diode will drop by about 2.1 mV/°C (negative temperature coefficient, NTC). For a Ge diode this NTC is a bit higher at 2.5 mV/°C.
The effect is almost perfectly linear, so if you want you can make the diode a temperature sensor by supplying it with a constant current.

Reverse current increases exponentially with rising temperature. For a 1N4148 it increases tenfold for every 20°C temperature rise.

stevenvh
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  • first of all , thanks for your answer.Lastly,I want to a question.What websites&books can you recommended related semiconductor devices? – Cell-o Apr 18 '11 at 09:44
  • @Cell-o - The question about electronics books has been asked a few times in the past, read e.g. http://electronics.stackexchange.com/questions/4795/books-for-basic-electronics – stevenvh Apr 18 '11 at 09:51
  • @stevenvh, this is specifically for Si diodes, or does this apply to all diodes. – Kortuk May 05 '11 at 09:19
  • @Kortuk - this is for Si, I'll add this to the answer. Ge diodes have a higher tempco. Don't know the exact value though. – stevenvh May 05 '11 at 11:17
  • @Stevenvh, I was 99% sure of that, but thought I should ask, figured a short and sweet answer needed that added. – Kortuk May 05 '11 at 11:27
  • @Stevenvh - what is the reverse recovery time in diode? – Cell-o May 05 '11 at 12:10
  • @Cell-o - That question is (mostly) unrelated to the effect of temperature on a diode. Please post it as a new question, if it's not a duplicate of [this question](http://electronics.stackexchange.com/questions/3821/what-is-a-fast-2a-type-diode). – Kevin Vermeer May 05 '11 at 13:14