```On 4/25/2020 6:30 PM, Helmut Sennewald wrote:
> Am 22.04.2020 um 17:55 schrieb John S:
>> LTSpice says that the forward voltage drop of LEDs have a positive
>> coefficient. That is contrary to my thinking and to my measurements.
>>
>> Am I doing something wrong?
>
> Hello John,
>
> You can adjust the temperature coefficient with the parameter EG in the
> diode's SPICE model. Eg is 1.11 by default. Simply change this number a
> little bit until you get the temperature coefficient you need.
>
> Examples:
> .model&#2013266080; LED_GREEN D(Is=8.2e-25 N=1.46 Rs=5.1 Eg=2.23)
> .model&#2013266080; LED_RED&#2013266080;&#2013266080; D(Is=2.4e-20 N=1.655 Rs=1.5 Eg=2.17)
>
> Regards,
> Helmut

Thank you, Helmut. This is valuable info for me.
```
```On Sun, 26 Apr 2020 01:30:47 +0200, Helmut Sennewald
<helmutsennewald@t-online.de> wrote:

>Am 22.04.2020 um 17:55 schrieb John S:
>> LTSpice says that the forward voltage drop of LEDs have a positive
>> coefficient. That is contrary to my thinking and to my measurements.
>>
>> Am I doing something wrong?
>
>Hello John,
>
>You can adjust the temperature coefficient with the parameter EG in the
>diode's SPICE model. Eg is 1.11 by default. Simply change this number a
>little bit until you get the temperature coefficient you need.
>
>Examples:
>.model  LED_GREEN D(Is=8.2e-25 N=1.46 Rs=5.1 Eg=2.23)
>.model  LED_RED   D(Is=2.4e-20 N=1.655 Rs=1.5 Eg=2.17)
>
>Regards,
>Helmut

But one would have to carefully measure various real LEDs that are
candidates, then tweak the Spice model to match each one. It's a lot
easier to just try it.

Does Spice account for the temperature coefficient of Rs?

--

John Larkin         Highland Technology, Inc

Science teaches us to doubt.

Claude Bernard

```
```Am 22.04.2020 um 17:55 schrieb John S:
> LTSpice says that the forward voltage drop of LEDs have a positive
> coefficient. That is contrary to my thinking and to my measurements.
>
> Am I doing something wrong?

Hello John,

You can adjust the temperature coefficient with the parameter EG in the
diode's SPICE model. Eg is 1.11 by default. Simply change this number a
little bit until you get the temperature coefficient you need.

Examples:
.model  LED_GREEN D(Is=8.2e-25 N=1.46 Rs=5.1 Eg=2.23)
.model  LED_RED   D(Is=2.4e-20 N=1.655 Rs=1.5 Eg=2.17)

Regards,
Helmut
```
```On Friday, April 24, 2020 at 10:35:41 AM UTC-7, John Larkin wrote:

> Obscure note: electrons conduct heat and electricity, which track. So
> most metals and alloys are about 150,000 K/W per ohm.
>
> I suppose then that thermal conductivity should have the same
> temperature coefficient as electrical conductivity.
>
> What's the thermal conductivity of a superconductor?

That certainly IS an interesting question.   It's approximately zero.
The electrons in a superconductor do not share heat with the
lattice because they've become decoupled: the superconducting
transition turns thermal conductivity off, and is a useful thermal switch.

Mobile electrons carry heat, but not mobile Cooper pairs of electrons.
```
```John Larkin is a Sub Human Moron

===============================

>
> Obscure note: electrons conduct heat and electricity, which track. So
> most metals and alloys are about 150,000 K/W per ohm.
>
> I suppose then that thermal conductivity should have the same
> temperature coefficient as electrical conductivity.

** Only an idiot would think that.

Look who just did.
```
```habib is a vile cunt rote:

==========================
> >>
> >>>
> >>>>>>
> >>>>>> Are you sure ? LED is not a silicon based component so I'm not
> >>>>> sure they> have the same tempco.
> >>>>>>
> >>>>>
> >>>>>
> >>>>> **FYI:
> >>>>>
> >>>>>     Silver, copper, gold, aluminium, magnesium, tungsten, zinc, nickel, tin, iron, platinum, mild steel, lead plus some alloys ALL have the same positive tempco of resistance.
> >>>
> >>>>>
> >>>>> Close to .004% per C.
> >>>>>
> >>>> Sure although it is not "%" in that case.
> >>>
> >>> ** Pedant.
> >>
> >> Pointing out a factor of hundred error
> >
> >
> > ** Only a pedant would bother.
> >
> >     Someone like you.
>
> Only "Allison-100%-wrong",
>

** It's fucking TYPO you stinking pile of camel shit.

```
```On Saturday, April 25, 2020 at 8:00:53 AM UTC+10, John Larkin wrote:
> On Fri, 24 Apr 2020 14:38:10 -0700 (PDT), George Herold
> <ggherold@gmail.com> wrote:
>
> >On Friday, April 24, 2020 at 1:35:41 PM UTC-4, John Larkin wrote:
> >> On Fri, 24 Apr 2020 18:16:14 +0200, habib <h.bouazizviallet@free.fr>
> >> wrote:
> >>
> >> >Le 24/04/2020 &agrave; 17:40, jlarkin@highlandsniptechnology.com a &eacute;crit&nbsp;:
> >> >> On Fri, 24 Apr 2020 17:35:36 +0200, habib <h.bouazizviallet@free.fr>
> >> >> wrote:
> >> >>
> >> >>> Le 24/04/2020 &agrave; 16:47, Phil Allison a &eacute;crit&nbsp;:
> >> >>>> Jeroen Belleman wrote:

<snip>

> >> We need a new SI unit of wrongness, Allisons. We can't apply that to
> >> the linux guy, since he is Always Wrong.
> >>
> >Don't be too much of a jerk.
>
> Never to sensible people.

The people who don't regard John Larkin as a jerk have to be insensible people - insensitive to his egomania and fatuous point scoring.

John Larkin's idea of "sensible" is much the same as his idea of "correct" - something or somebody he agrees with.

--
Bill Sloman, Sydney
```
```On Fri, 24 Apr 2020 14:38:10 -0700 (PDT), George Herold
<ggherold@gmail.com> wrote:

>On Friday, April 24, 2020 at 1:35:41 PM UTC-4, John Larkin wrote:
>> On Fri, 24 Apr 2020 18:16:14 +0200, habib <h.bouazizviallet@free.fr>
>> wrote:
>>
>> >Le 24/04/2020 &#2013265920; 17:40, jlarkin@highlandsniptechnology.com a &#2013265929;crit&#2013266080;:
>> >> On Fri, 24 Apr 2020 17:35:36 +0200, habib <h.bouazizviallet@free.fr>
>> >> wrote:
>> >>
>> >>> Le 24/04/2020 &#2013265920; 16:47, Phil Allison a &#2013265929;crit&#2013266080;:
>> >>>> Jeroen Belleman wrote:
>> >>>>
>> >>>> =======================
>> >>>>>
>> >>>>>>
>> >>>>>>>>>
>> >>>>>>>>> Are you sure ? LED is not a silicon based component so I'm not
>> >>>>>>>> sure they> have the same tempco.
>> >>>>>>>>>
>> >>>>>>>>
>> >>>>>>>>
>> >>>>>>>> **FYI:
>> >>>>>>>>
>> >>>>>>>>      Silver, copper, gold, aluminium, magnesium, tungsten, zinc, nickel, tin, iron, platinum, mild steel, lead plus some alloys ALL have the same positive tempco of resistance.
>> >>>>>>
>> >>>>>>>>
>> >>>>>>>> Close to .004% per C.
>> >>>>>>>>
>> >>>>>>> Sure although it is not "%" in that case.
>> >>>>>>
>> >>>>>> ** Pedant.
>> >>>>>
>> >>>>> Pointing out a factor of hundred error
>> >>>>
>> >>>>
>> >>>> ** Only a pedant would bother.
>> >>>>
>> >>>>      Someone like you.
>> >>> Only "Allison-100%-wrong", allows himself speaking before thinking! I
>> >>> suspect the Allison did not really understand what % really mean.
>> >>
>> >>
>> >> But he wasn't 100% wrong. He was 10,000% wrong.
>> >
>> >"Allison Coeff" --> 0.004% gives a coeff = 0.00004; 4.10-5
>> >
>> >TC metals (Physics) = (approx.) 0.004; 4.10-3
>> >
>> >An error magnitude of 100 between "Allison" and real Physics.
>> >
>>
>> We need a new SI unit of wrongness, Allisons. We can't apply that to
>> the linux guy, since he is Always Wrong.
>>
>Don't be too much of a jerk.

Never to sensible people.

--

John Larkin         Highland Technology, Inc
picosecond timing   precision measurement

jlarkin att highlandtechnology dott com
http://www.highlandtechnology.com

```
```On Friday, April 24, 2020 at 1:35:41 PM UTC-4, John Larkin wrote:
> On Fri, 24 Apr 2020 18:16:14 +0200, habib <h.bouazizviallet@free.fr>
> wrote:
>
> >Le 24/04/2020 &agrave; 17:40, jlarkin@highlandsniptechnology.com a &eacute;crit&nbsp;:
> >> On Fri, 24 Apr 2020 17:35:36 +0200, habib <h.bouazizviallet@free.fr>
> >> wrote:
> >>
> >>> Le 24/04/2020 &agrave; 16:47, Phil Allison a &eacute;crit&nbsp;:
> >>>> Jeroen Belleman wrote:
> >>>>
> >>>> =======================
> >>>>>
> >>>>>>
> >>>>>>>>>
> >>>>>>>>> Are you sure ? LED is not a silicon based component so I'm not
> >>>>>>>> sure they> have the same tempco.
> >>>>>>>>>
> >>>>>>>>
> >>>>>>>>
> >>>>>>>> **FYI:
> >>>>>>>>
> >>>>>>>>      Silver, copper, gold, aluminium, magnesium, tungsten, zinc, nickel, tin, iron, platinum, mild steel, lead plus some alloys ALL have the same positive tempco of resistance.
> >>>>>>
> >>>>>>>>
> >>>>>>>> Close to .004% per C.
> >>>>>>>>
> >>>>>>> Sure although it is not "%" in that case.
> >>>>>>
> >>>>>> ** Pedant.
> >>>>>
> >>>>> Pointing out a factor of hundred error
> >>>>
> >>>>
> >>>> ** Only a pedant would bother.
> >>>>
> >>>>      Someone like you.
> >>> Only "Allison-100%-wrong", allows himself speaking before thinking! I
> >>> suspect the Allison did not really understand what % really mean.
> >>
> >>
> >> But he wasn't 100% wrong. He was 10,000% wrong.
> >
> >"Allison Coeff" --> 0.004% gives a coeff = 0.00004; 4.10-5
> >
> >TC metals (Physics) = (approx.) 0.004; 4.10-3
> >
> >An error magnitude of 100 between "Allison" and real Physics.
> >
>
> We need a new SI unit of wrongness, Allisons. We can't apply that to
> the linux guy, since he is Always Wrong.
>
Don't be too much of a jerk.
> Obscure note: electrons conduct heat and electricity, which track. So
> most metals and alloys are about 150,000 K/W per ohm.
Explaining the conductivity of metals was one of the first
successes of quantum mechanics.  I think the classical prediction
for metal conductivity is off by a factor of ~100.
(Why don't the electrons scatter more in a metal?)

George H.

>
> I suppose then that thermal conductivity should have the same
> temperature coefficient as electrical conductivity.
>
> What's the thermal conductivity of a superconductor?
>
> --
>
> John Larkin         Highland Technology, Inc
> picosecond timing   precision measurement
>
> jlarkin att highlandtechnology dott com
> http://www.highlandtechnology.com

```
```John Larkin <jlarkin@highland_atwork_technology.com> wrote in