PS
Perry Sandeen
Tue, Jan 17, 2017 3:33 AM
List,
A while back there was much discussion about temperature sensors.
One simple inexpensive one to consider would be the ZNI1000Temperature sensor.
It's 1K ohms at 0C and it replicates the temperature curve of the Pt 1K ohm sensors.
It's about $3 from Digi-Key.
FWIW YMMY
Regards,
Perrier
List,
A while back there was much discussion about temperature sensors.
One simple inexpensive one to consider would be the ZNI1000Temperature sensor.
It's 1K ohms at 0C and it replicates the temperature curve of the Pt 1K ohm sensors.
It's about $3 from Digi-Key.
FWIW YMMY
Regards,
Perrier
BH
Bill Hawkins
Tue, Jan 17, 2017 5:16 AM
Perrier,
Google finds a Siemens NI1000 sensor that follows the nickel curve.
Nickel is popular in industrial control for cost, but not as accurate as
platinum. Converting the platinum curve to accurate temperatures
requires a second order equation, but has been done with 0.1% analog
converters.
Digi-key has ZNI devices as surface mount parts. Sparse data said
nothing about a platinum curve.
I'm curious because my former employer did very well selling platinum
RTD sensors, usually 100 ohms at the triple point.
Bill Hawkins
-----Original Message-----
From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Perry
Sandeen via time-nuts
Sent: Monday, January 16, 2017 9:33 PM
To: time-nuts@febo.com
Subject: [time-nuts] Low CostTemperature sensor
List,
A while back there was much discussion about temperature sensors.
One simple inexpensive one to consider would be the ZNI1000Temperature
sensor.
It's 1K ohms at 0C and it replicates the temperature curve of the Pt 1K
ohm sensors.
It's about $3 from Digi-Key.
FWIW YMMY
Regards,
Perrier
time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
Perrier,
Google finds a Siemens NI1000 sensor that follows the nickel curve.
Nickel is popular in industrial control for cost, but not as accurate as
platinum. Converting the platinum curve to accurate temperatures
requires a second order equation, but has been done with 0.1% analog
converters.
Digi-key has ZNI devices as surface mount parts. Sparse data said
nothing about a platinum curve.
I'm curious because my former employer did very well selling platinum
RTD sensors, usually 100 ohms at the triple point.
Bill Hawkins
-----Original Message-----
From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Perry
Sandeen via time-nuts
Sent: Monday, January 16, 2017 9:33 PM
To: time-nuts@febo.com
Subject: [time-nuts] Low CostTemperature sensor
List,
A while back there was much discussion about temperature sensors.
One simple inexpensive one to consider would be the ZNI1000Temperature
sensor.
It's 1K ohms at 0C and it replicates the temperature curve of the Pt 1K
ohm sensors.
It's about $3 from Digi-Key.
FWIW YMMY
Regards,
Perrier
_______________________________________________
time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
JB
Jason Ball
Tue, Jan 17, 2017 6:11 AM
Perrier,
Google finds a Siemens NI1000 sensor that follows the nickel curve.
Nickel is popular in industrial control for cost, but not as accurate as
platinum. Converting the platinum curve to accurate temperatures
requires a second order equation, but has been done with 0.1% analog
converters.
Digi-key has ZNI devices as surface mount parts. Sparse data said
nothing about a platinum curve.
I'm curious because my former employer did very well selling platinum
RTD sensors, usually 100 ohms at the triple point.
Bill Hawkins
-----Original Message-----
From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Perry
Sandeen via time-nuts
Sent: Monday, January 16, 2017 9:33 PM
To: time-nuts@febo.com
Subject: [time-nuts] Low CostTemperature sensor
List,
A while back there was much discussion about temperature sensors.
One simple inexpensive one to consider would be the ZNI1000Temperature
sensor.
It's 1K ohms at 0C and it replicates the temperature curve of the Pt 1K
ohm sensors.
It's about $3 from Digi-Key.
FWIW YMMY
Regards,
Perrier
time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/
mailman/listinfo/time-nuts
and follow the instructions there.
Even cheaper... Diiode as a cheap sensor ?
https://www.arrow.com/en/research-and-events/articles/using-a-simple-diode-as-a-ballpark-temperature-sensor
On Tue, Jan 17, 2017 at 4:16 PM, Bill Hawkins <bill.iaxs@pobox.com> wrote:
> Perrier,
>
> Google finds a Siemens NI1000 sensor that follows the nickel curve.
> Nickel is popular in industrial control for cost, but not as accurate as
> platinum. Converting the platinum curve to accurate temperatures
> requires a second order equation, but has been done with 0.1% analog
> converters.
>
> Digi-key has ZNI devices as surface mount parts. Sparse data said
> nothing about a platinum curve.
>
> I'm curious because my former employer did very well selling platinum
> RTD sensors, usually 100 ohms at the triple point.
>
> Bill Hawkins
>
>
> -----Original Message-----
> From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Perry
> Sandeen via time-nuts
> Sent: Monday, January 16, 2017 9:33 PM
> To: time-nuts@febo.com
> Subject: [time-nuts] Low CostTemperature sensor
>
> List,
> A while back there was much discussion about temperature sensors.
> One simple inexpensive one to consider would be the ZNI1000Temperature
> sensor.
> It's 1K ohms at 0C and it replicates the temperature curve of the Pt 1K
> ohm sensors.
> It's about $3 from Digi-Key.
> FWIW YMMY
> Regards,
> Perrier
> _______________________________________________
> time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
>
> _______________________________________________
> time-nuts mailing list -- time-nuts@febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/
> mailman/listinfo/time-nuts
> and follow the instructions there.
>
--
--
Teach your kids Science, or somebody else will :/
jason@ball.net
vk2vjb@google.com <vk2flnx@google.com>
callsign: vk2vjb
TM
Tom Miller
Tue, Jan 17, 2017 6:52 AM
That article has a major error. Anyone know what it is?
----- Original Message -----
From: "Jason Ball" jason@ball.net
To: "Discussion of precise time and frequency measurement"
time-nuts@febo.com
Cc: "Perry Sandeen" sandeenpa@yahoo.com
Sent: Tuesday, January 17, 2017 1:11 AM
Subject: Re: [time-nuts] Low CostTemperature sensor
Perrier,
Google finds a Siemens NI1000 sensor that follows the nickel curve.
Nickel is popular in industrial control for cost, but not as accurate as
platinum. Converting the platinum curve to accurate temperatures
requires a second order equation, but has been done with 0.1% analog
converters.
Digi-key has ZNI devices as surface mount parts. Sparse data said
nothing about a platinum curve.
I'm curious because my former employer did very well selling platinum
RTD sensors, usually 100 ohms at the triple point.
Bill Hawkins
-----Original Message-----
From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Perry
Sandeen via time-nuts
Sent: Monday, January 16, 2017 9:33 PM
To: time-nuts@febo.com
Subject: [time-nuts] Low CostTemperature sensor
List,
A while back there was much discussion about temperature sensors.
One simple inexpensive one to consider would be the ZNI1000Temperature
sensor.
It's 1K ohms at 0C and it replicates the temperature curve of the Pt 1K
ohm sensors.
It's about $3 from Digi-Key.
FWIW YMMY
Regards,
Perrier
time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/
mailman/listinfo/time-nuts
and follow the instructions there.
That article has a major error. Anyone know what it is?
----- Original Message -----
From: "Jason Ball" <jason@ball.net>
To: "Discussion of precise time and frequency measurement"
<time-nuts@febo.com>
Cc: "Perry Sandeen" <sandeenpa@yahoo.com>
Sent: Tuesday, January 17, 2017 1:11 AM
Subject: Re: [time-nuts] Low CostTemperature sensor
> Even cheaper... Diiode as a cheap sensor ?
>
> https://www.arrow.com/en/research-and-events/articles/using-a-simple-diode-as-a-ballpark-temperature-sensor
>
>
> On Tue, Jan 17, 2017 at 4:16 PM, Bill Hawkins <bill.iaxs@pobox.com> wrote:
>
>> Perrier,
>>
>> Google finds a Siemens NI1000 sensor that follows the nickel curve.
>> Nickel is popular in industrial control for cost, but not as accurate as
>> platinum. Converting the platinum curve to accurate temperatures
>> requires a second order equation, but has been done with 0.1% analog
>> converters.
>>
>> Digi-key has ZNI devices as surface mount parts. Sparse data said
>> nothing about a platinum curve.
>>
>> I'm curious because my former employer did very well selling platinum
>> RTD sensors, usually 100 ohms at the triple point.
>>
>> Bill Hawkins
>>
>>
>> -----Original Message-----
>> From: time-nuts [mailto:time-nuts-bounces@febo.com] On Behalf Of Perry
>> Sandeen via time-nuts
>> Sent: Monday, January 16, 2017 9:33 PM
>> To: time-nuts@febo.com
>> Subject: [time-nuts] Low CostTemperature sensor
>>
>> List,
>> A while back there was much discussion about temperature sensors.
>> One simple inexpensive one to consider would be the ZNI1000Temperature
>> sensor.
>> It's 1K ohms at 0C and it replicates the temperature curve of the Pt 1K
>> ohm sensors.
>> It's about $3 from Digi-Key.
>> FWIW YMMY
>> Regards,
>> Perrier
>> _______________________________________________
>> time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to
>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>> and follow the instructions there.
>>
>> _______________________________________________
>> time-nuts mailing list -- time-nuts@febo.com
>> To unsubscribe, go to https://www.febo.com/cgi-bin/
>> mailman/listinfo/time-nuts
>> and follow the instructions there.
>>
>
>
>
> --
> --
> Teach your kids Science, or somebody else will :/
>
> jason@ball.net
> vk2vjb@google.com <vk2flnx@google.com>
> callsign: vk2vjb
> _______________________________________________
> time-nuts mailing list -- time-nuts@febo.com
> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
CS
Charles Steinmetz
Tue, Jan 17, 2017 9:17 AM
That article has a major error. Anyone know what it is?
Well, the author says the reverse current of a diode is "directly"
proportional to temperature. This could suggest that he means the
relationship is linear (the relationship is actually exponential with
absolute temperature). But that's not really an error -- just sloppy.
"Direct" does not necessarily imply "linear." An exponential
relationship is "direct" in the sense that it is what mathematicians
call "injective" (every temperature corresponds to exactly one value of
reverse current).
Then, in discussing the LM95235, he says that it can use the
"collector-emitter junction diode" of a transistor as the sense element.
Of course, a bipolar transistor has no collector-emitter junction.
His diagram correctly shows a diode-connected NPN operating in the
active region (forward biased, not reverse biased as the rest of his
article discusses) as the sensor for the LM95235.
Are any of these what you had in mind, or is there more?
Charles
Tom wrote:
> That article has a major error. Anyone know what it is?
Well, the author says the reverse current of a diode is "directly"
proportional to temperature. This could suggest that he means the
relationship is linear (the relationship is actually exponential with
absolute temperature). But that's not really an *error* -- just sloppy.
"Direct" does not necessarily imply "linear." An exponential
relationship is "direct" in the sense that it is what mathematicians
call "injective" (every temperature corresponds to exactly one value of
reverse current).
Then, in discussing the LM95235, he says that it can use the
"collector-emitter junction diode" of a transistor as the sense element.
Of course, a bipolar transistor has no collector-emitter junction.
His diagram correctly shows a diode-connected NPN operating in the
active region (forward biased, not reverse biased as the rest of his
article discusses) as the sensor for the LM95235.
Are any of these what you had in mind, or is there more?
Charles
SS
Scott Stobbe
Tue, Jan 17, 2017 2:10 PM
Thermometry based on Diode leakage current wouldn't be impossible I
suppose, you might loose some hair in the process.
The signal levels on the opamp are goofed too.
On Tue, Jan 17, 2017 at 4:19 AM Charles Steinmetz csteinmetz@yandex.com
wrote:
That article has a major error. Anyone know what it is?
Well, the author says the reverse current of a diode is "directly"
proportional to temperature. This could suggest that he means the
relationship is linear (the relationship is actually exponential with
absolute temperature). But that's not really an error -- just sloppy.
"Direct" does not necessarily imply "linear." An exponential
relationship is "direct" in the sense that it is what mathematicians
call "injective" (every temperature corresponds to exactly one value of
reverse current).
Then, in discussing the LM95235, he says that it can use the
"collector-emitter junction diode" of a transistor as the sense element.
Of course, a bipolar transistor has no collector-emitter junction.
His diagram correctly shows a diode-connected NPN operating in the
active region (forward biased, not reverse biased as the rest of his
article discusses) as the sensor for the LM95235.
Are any of these what you had in mind, or is there more?
Charles
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
Thermometry based on Diode leakage current wouldn't be impossible I
suppose, you might loose some hair in the process.
The signal levels on the opamp are goofed too.
On Tue, Jan 17, 2017 at 4:19 AM Charles Steinmetz <csteinmetz@yandex.com>
wrote:
> Tom wrote:
>
>
>
> > That article has a major error. Anyone know what it is?
>
>
>
> Well, the author says the reverse current of a diode is "directly"
>
> proportional to temperature. This could suggest that he means the
>
> relationship is linear (the relationship is actually exponential with
>
> absolute temperature). But that's not really an *error* -- just sloppy.
>
> "Direct" does not necessarily imply "linear." An exponential
>
> relationship is "direct" in the sense that it is what mathematicians
>
> call "injective" (every temperature corresponds to exactly one value of
>
> reverse current).
>
>
>
> Then, in discussing the LM95235, he says that it can use the
>
> "collector-emitter junction diode" of a transistor as the sense element.
>
> Of course, a bipolar transistor has no collector-emitter junction.
>
> His diagram correctly shows a diode-connected NPN operating in the
>
> active region (forward biased, not reverse biased as the rest of his
>
> article discusses) as the sensor for the LM95235.
>
>
>
> Are any of these what you had in mind, or is there more?
>
>
>
> Charles
>
>
>
> _______________________________________________
>
> time-nuts mailing list -- time-nuts@febo.com
>
> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>
> and follow the instructions there.
>
>
TM
Tom Miller
Tue, Jan 17, 2017 4:14 PM
I agree with both of you. I can't imagine using the reverse leakage of a
diode to measure temperature without some difficult and expensive design.
Also, the transistor is using the forward biased B-E diode against what he
stated in the article.
And sloppy would be the best description.
Thanks guys. Glad I am not the only one forming that opinion.
Regards,
Tom
----- Original Message -----
From: "Scott Stobbe" scott.j.stobbe@gmail.com
To: "Discussion of precise time and frequency measurement"
time-nuts@febo.com
Sent: Tuesday, January 17, 2017 9:10 AM
Subject: Re: [time-nuts] Low CostTemperature sensor
Thermometry based on Diode leakage current wouldn't be impossible I
suppose, you might loose some hair in the process.
The signal levels on the opamp are goofed too.
On Tue, Jan 17, 2017 at 4:19 AM Charles Steinmetz csteinmetz@yandex.com
wrote:
That article has a major error. Anyone know what it is?
Well, the author says the reverse current of a diode is "directly"
proportional to temperature. This could suggest that he means the
relationship is linear (the relationship is actually exponential with
absolute temperature). But that's not really an error -- just sloppy.
"Direct" does not necessarily imply "linear." An exponential
relationship is "direct" in the sense that it is what mathematicians
call "injective" (every temperature corresponds to exactly one value of
reverse current).
Then, in discussing the LM95235, he says that it can use the
"collector-emitter junction diode" of a transistor as the sense element.
Of course, a bipolar transistor has no collector-emitter junction.
His diagram correctly shows a diode-connected NPN operating in the
active region (forward biased, not reverse biased as the rest of his
article discusses) as the sensor for the LM95235.
Are any of these what you had in mind, or is there more?
Charles
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
I agree with both of you. I can't imagine using the reverse leakage of a
diode to measure temperature without some difficult and expensive design.
Also, the transistor is using the forward biased B-E diode against what he
stated in the article.
And sloppy would be the best description.
Thanks guys. Glad I am not the only one forming that opinion.
Regards,
Tom
----- Original Message -----
From: "Scott Stobbe" <scott.j.stobbe@gmail.com>
To: "Discussion of precise time and frequency measurement"
<time-nuts@febo.com>
Sent: Tuesday, January 17, 2017 9:10 AM
Subject: Re: [time-nuts] Low CostTemperature sensor
> Thermometry based on Diode leakage current wouldn't be impossible I
> suppose, you might loose some hair in the process.
>
> The signal levels on the opamp are goofed too.
>
> On Tue, Jan 17, 2017 at 4:19 AM Charles Steinmetz <csteinmetz@yandex.com>
> wrote:
>
>> Tom wrote:
>>
>>
>>
>> > That article has a major error. Anyone know what it is?
>>
>>
>>
>> Well, the author says the reverse current of a diode is "directly"
>>
>> proportional to temperature. This could suggest that he means the
>>
>> relationship is linear (the relationship is actually exponential with
>>
>> absolute temperature). But that's not really an *error* -- just sloppy.
>>
>> "Direct" does not necessarily imply "linear." An exponential
>>
>> relationship is "direct" in the sense that it is what mathematicians
>>
>> call "injective" (every temperature corresponds to exactly one value of
>>
>> reverse current).
>>
>>
>>
>> Then, in discussing the LM95235, he says that it can use the
>>
>> "collector-emitter junction diode" of a transistor as the sense element.
>>
>> Of course, a bipolar transistor has no collector-emitter junction.
>>
>> His diagram correctly shows a diode-connected NPN operating in the
>>
>> active region (forward biased, not reverse biased as the rest of his
>>
>> article discusses) as the sensor for the LM95235.
>>
>>
>>
>> Are any of these what you had in mind, or is there more?
>>
>>
>>
>> Charles
>>
>>
>>
>> _______________________________________________
>>
>> time-nuts mailing list -- time-nuts@febo.com
>>
>> To unsubscribe, go to
>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>>
>> and follow the instructions there.
>>
>>
> _______________________________________________
> time-nuts mailing list -- time-nuts@febo.com
> To unsubscribe, go to
> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
> and follow the instructions there.
OE
Orin Eman
Tue, Jan 17, 2017 5:46 PM
Directly proportional implies a relationship of the form y = c * x where c
is a constant and * is multiplication. So it is linear.
To call an exponential relationship "directly proportional" would be wrong.
On Tue, Jan 17, 2017 at 1:17 AM, Charles Steinmetz csteinmetz@yandex.com
wrote:
Tom wrote:
That article has a major error. Anyone know what it is?
Well, the author says the reverse current of a diode is "directly"
proportional to temperature. This could suggest that he means the
relationship is linear (the relationship is actually exponential with
absolute temperature). But that's not really an error -- just sloppy.
"Direct" does not necessarily imply "linear." An exponential relationship
is "direct" in the sense that it is what mathematicians call "injective"
(every temperature corresponds to exactly one value of reverse current).
Then, in discussing the LM95235, he says that it can use the
"collector-emitter junction diode" of a transistor as the sense element.
Of course, a bipolar transistor has no collector-emitter junction. His
diagram correctly shows a diode-connected NPN operating in the active
region (forward biased, not reverse biased as the rest of his article
discusses) as the sensor for the LM95235.
Are any of these what you had in mind, or is there more?
Charles
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/m
ailman/listinfo/time-nuts
and follow the instructions there.
Directly proportional implies a relationship of the form y = c * x where c
is a constant and * is multiplication. So it is linear.
To call an exponential relationship "directly proportional" would be wrong.
On Tue, Jan 17, 2017 at 1:17 AM, Charles Steinmetz <csteinmetz@yandex.com>
wrote:
> Tom wrote:
>
> That article has a major error. Anyone know what it is?
>>
>
> Well, the author says the reverse current of a diode is "directly"
> proportional to temperature. This could suggest that he means the
> relationship is linear (the relationship is actually exponential with
> absolute temperature). But that's not really an *error* -- just sloppy.
> "Direct" does not necessarily imply "linear." An exponential relationship
> is "direct" in the sense that it is what mathematicians call "injective"
> (every temperature corresponds to exactly one value of reverse current).
>
> Then, in discussing the LM95235, he says that it can use the
> "collector-emitter junction diode" of a transistor as the sense element.
> Of course, a bipolar transistor has no collector-emitter junction. His
> diagram correctly shows a diode-connected NPN operating in the active
> region (forward biased, not reverse biased as the rest of his article
> discusses) as the sensor for the LM95235.
>
> Are any of these what you had in mind, or is there more?
>
> Charles
>
> _______________________________________________
> time-nuts mailing list -- time-nuts@febo.com
> To unsubscribe, go to https://www.febo.com/cgi-bin/m
> ailman/listinfo/time-nuts
> and follow the instructions there.
>
WH
William H. Fite
Tue, Jan 17, 2017 8:09 PM
Orin is correct. To refer to an exponential relationship as directly
proportional is erroneous yet people use it that way commonly and everybody
knows what they mean. It just sets the teeth of statisticians like me on
edge.
On Tue, Jan 17, 2017 at 12:46 PM, Orin Eman orin.eman@gmail.com wrote:
Directly proportional implies a relationship of the form y = c * x where c
is a constant and * is multiplication. So it is linear.
To call an exponential relationship "directly proportional" would be wrong.
On Tue, Jan 17, 2017 at 1:17 AM, Charles Steinmetz csteinmetz@yandex.com
wrote:
Tom wrote:
That article has a major error. Anyone know what it is?
Well, the author says the reverse current of a diode is "directly"
proportional to temperature. This could suggest that he means the
relationship is linear (the relationship is actually exponential with
absolute temperature). But that's not really an error -- just sloppy.
"Direct" does not necessarily imply "linear." An exponential
is "direct" in the sense that it is what mathematicians call "injective"
(every temperature corresponds to exactly one value of reverse current).
Then, in discussing the LM95235, he says that it can use the
"collector-emitter junction diode" of a transistor as the sense element.
Of course, a bipolar transistor has no collector-emitter junction. His
diagram correctly shows a diode-connected NPN operating in the active
region (forward biased, not reverse biased as the rest of his article
discusses) as the sensor for the LM95235.
Are any of these what you had in mind, or is there more?
Charles
time-nuts mailing list -- time-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/m
ailman/listinfo/time-nuts
and follow the instructions there.
--
Intelligence has never been proof against stupidity.
Orin is correct. To refer to an exponential relationship as directly
proportional is erroneous yet people use it that way commonly and everybody
knows what they mean. It just sets the teeth of statisticians like me on
edge.
On Tue, Jan 17, 2017 at 12:46 PM, Orin Eman <orin.eman@gmail.com> wrote:
> Directly proportional implies a relationship of the form y = c * x where c
> is a constant and * is multiplication. So it is linear.
>
> To call an exponential relationship "directly proportional" would be wrong.
>
> On Tue, Jan 17, 2017 at 1:17 AM, Charles Steinmetz <csteinmetz@yandex.com>
> wrote:
>
> > Tom wrote:
> >
> > That article has a major error. Anyone know what it is?
> >>
> >
> > Well, the author says the reverse current of a diode is "directly"
> > proportional to temperature. This could suggest that he means the
> > relationship is linear (the relationship is actually exponential with
> > absolute temperature). But that's not really an *error* -- just sloppy.
> > "Direct" does not necessarily imply "linear." An exponential
> relationship
> > is "direct" in the sense that it is what mathematicians call "injective"
> > (every temperature corresponds to exactly one value of reverse current).
> >
> > Then, in discussing the LM95235, he says that it can use the
> > "collector-emitter junction diode" of a transistor as the sense element.
> > Of course, a bipolar transistor has no collector-emitter junction. His
> > diagram correctly shows a diode-connected NPN operating in the active
> > region (forward biased, not reverse biased as the rest of his article
> > discusses) as the sensor for the LM95235.
> >
> > Are any of these what you had in mind, or is there more?
> >
> > Charles
> >
> > _______________________________________________
> > time-nuts mailing list -- time-nuts@febo.com
> > To unsubscribe, go to https://www.febo.com/cgi-bin/m
> > ailman/listinfo/time-nuts
> > and follow the instructions there.
> >
> _______________________________________________
> time-nuts mailing list -- time-nuts@febo.com
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--
Intelligence has never been proof against stupidity.
