Re: Unusual Characteristic [LOL]

From: John Larkin (jjlarkin_at_highlandSNIPtechTHISnologyPLEASE.com)
Date: 08/03/04 

Date: Mon, 02 Aug 2004 19:59:37 -0700

On 30 Jul 2004 21:27:25 GMT, Ian Stirling <root@mauve.demon.co.uk>
wrote:

>Michael A. Covington <look@ai.uga.edu.for.address> wrote:
>>
>> "Spehro Pefhany" <speffSNIP@interlogDOTyou.knowwhat> wrote in message
>> news:itnig0he8tgu1dn84a7h491o4bmmbkh9fv@4ax.com...
>>>
>>> "White LED's have the unusual property of having a
>>> variable forward voltage drop dependent on current."
>>>
>>> ".. typically have a 3.3 volt drop with 15mA of forward
>>> current and a 3.8 volt drop with 75mA of current".
>>
>> As if nothing else did :) :)
>>
>> I've never met an LED that didn't have a variable forward voltage drop with
>> current, partly due to internal resistance, and partly due to the
>> logarithmic diode characteristic.
>
>Could a tunnel LED be made?

Probably not. The small forward drop in the tunneling region would be
such a low voltage that the corresponding wavelength would be very
long. Might be a way to get very deep IR, though.

John

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