programmable resistors?
https://www.sciencedaily.com/releases/2022/07/220728142923.htm

On Fri, 29 Jul 2022 06:17:01 GMT, Jan Panteltje
<pNaonStpealmtje@yahoo.com> wrote:

>programmable resistors?
> https://www.sciencedaily.com/releases/2022/07/220728142923.htm

One real-world problem is, how do you make a wide-range bipolar
reasonably-wideband accurate low-noise isolated resistor?

Some people do that with lots of resistors and relays, but electronic
is more interesting.

jlarkin@highlandsniptechnology.com wrote:
> On Fri, 29 Jul 2022 06:17:01 GMT, Jan Panteltje
> <pNaonStpealmtje@yahoo.com> wrote:
>
>> programmable resistors?
>> https://www.sciencedaily.com/releases/2022/07/220728142923.htm
>
> One real-world problem is, how do you make a wide-range bipolar
> reasonably-wideband accurate low-noise isolated

wideband

> resistor?
>
> Some people do that with lots of resistors and relays, but electronic
> is more interesting.
>

Interestingly, Murata will make custom laser-trimmed metal film resistor
arrays for pretty cheap. We're looking at using them in our next
generation variable-gain amplifier box.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

Jan Panteltje wrote:
> programmable resistors?
> <https://www.sciencedaily.com/releases/2022/07/220728142923.htm>

The working mechanism of the device is electrochemical
insertion of the smallest ion, the proton, into an
insulating oxide to modulate its electronic conductivity.

At this stage, protonic resistor research reminds me of nascence OLED
papers from 1990s. Sciencedaily's story source is an MIT press release:

<https://news.mit.edu/2022/analog-deep-learning-ai-computing-0728>

It's time for me to return to my RPi2 BSD port of your OLED project. :)

Danke,

--
Don, KB7RPU, https://www.qsl.net/kb7rpu
There was a young lady named Bright Whose speed was far faster than light;
She set out one day In a relative way And returned on the previous night.

On Fri, 29 Jul 2022 11:34:18 -0400, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

>jlarkin@highlandsniptechnology.com wrote:
>> On Fri, 29 Jul 2022 06:17:01 GMT, Jan Panteltje
>> <pNaonStpealmtje@yahoo.com> wrote:
>>
>>> programmable resistors?
>>> https://www.sciencedaily.com/releases/2022/07/220728142923.htm
>>
>> One real-world problem is, how do you make a wide-range bipolar
>> reasonably-wideband accurate low-noise isolated
>
>wideband

Kilohertz, to simulate RTDs mostly. A user might scan/mux RTDs and
might mux the excitation too, so we want sub-millisecond response but
not RF.

Circuit puzzle: How do you make an electronic wide-range bipolar
programmable resistor, say 0.1% accurate?

>
>> resistor?
>>
>> Some people do that with lots of resistors and relays, but electronic
>> is more interesting.
>>
>
>Interestingly, Murata will make custom laser-trimmed metal film resistor
>arrays for pretty cheap. We're looking at using them in our next
>generation variable-gain amplifier box.

We just ordered some stock quad 100K thinfilm packs, about 30 cents
each. You can make a mess of various values and dividers and opamp
gains from one quad pack.

John Larkin wrote:
> On Fri, 29 Jul 2022 11:34:18 -0400, Phil Hobbs
> <pcdhSpamMeSenseless@electrooptical.net> wrote:
>
>> jlarkin@highlandsniptechnology.com wrote:
>>> On Fri, 29 Jul 2022 06:17:01 GMT, Jan Panteltje
>>> <pNaonStpealmtje@yahoo.com> wrote:
>>>
>>>> programmable resistors?
>>>> https://www.sciencedaily.com/releases/2022/07/220728142923.htm
>>>
>>> One real-world problem is, how do you make a wide-range bipolar
>>> reasonably-wideband accurate low-noise isolated
>>
>> wideband
>
> Kilohertz, to simulate RTDs mostly. A user might scan/mux RTDs and
> might mux the excitation too, so we want sub-millisecond response but
> not RF.
>
> Circuit puzzle: How do you make an electronic wide-range bipolar
> programmable resistor, say 0.1% accurate?
>
>>
>>> resistor?
>>>
>>> Some people do that with lots of resistors and relays, but electronic
>>> is more interesting.
>>>
>>
>> Interestingly, Murata will make custom laser-trimmed metal film resistor
>> arrays for pretty cheap. We're looking at using them in our next
>> generation variable-gain amplifier box.

Probably a binary version of a resistor substitution box. Details
obviously depend a lot on the voltage range required.

> We just ordered some stock quad 100K thinfilm packs, about 30 cents
> each. You can make a mess of various values and dividers and opamp
> gains from one quad pack.

Yup. Our VGA gizmos use MDACs and switched resistors in various
combinations, depending on the bandwidth required. The point of them is
that the usual transconductance-based VCAs have really terrible noise
performance for larger signals. (Barrie Gilbert patented an idea for
using a whole lot of BJT pairs with their inputs wired in series to
improve this, but you can't buy any like that now.)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

On Fri, 29 Jul 2022 14:50:31 -0400, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

>John Larkin wrote:
>> On Fri, 29 Jul 2022 11:34:18 -0400, Phil Hobbs
>> <pcdhSpamMeSenseless@electrooptical.net> wrote:
>>
>>> jlarkin@highlandsniptechnology.com wrote:
>>>> On Fri, 29 Jul 2022 06:17:01 GMT, Jan Panteltje
>>>> <pNaonStpealmtje@yahoo.com> wrote:
>>>>
>>>>> programmable resistors?
>>>>> https://www.sciencedaily.com/releases/2022/07/220728142923.htm
>>>>
>>>> One real-world problem is, how do you make a wide-range bipolar
>>>> reasonably-wideband accurate low-noise isolated
>>>
>>> wideband
>>
>> Kilohertz, to simulate RTDs mostly. A user might scan/mux RTDs and
>> might mux the excitation too, so we want sub-millisecond response but
>> not RF.
>>
>> Circuit puzzle: How do you make an electronic wide-range bipolar
>> programmable resistor, say 0.1% accurate?
>>
>>>
>>>> resistor?
>>>>
>>>> Some people do that with lots of resistors and relays, but electronic
>>>> is more interesting.
>>>>
>>>
>>> Interestingly, Murata will make custom laser-trimmed metal film resistor
>>> arrays for pretty cheap. We're looking at using them in our next
>>> generation variable-gain amplifier box.
>
>Probably a binary version of a resistor substitution box. Details
>obviously depend a lot on the voltage range required.

Oh, another requirement is that resistance changes be monotonic and
glitch-free. An RTD simulator souldn't spike to 300C when it's
supposed to go from 25.2 to 25.3. Relay switched resistors have that
problem.

fredag den 29. juli 2022 kl. 16.24.59 UTC+2 skrev jla...@highlandsniptechnology.com:
> On Fri, 29 Jul 2022 06:17:01 GMT, Jan Panteltje
> <pNaonSt...@yahoo.com> wrote:
>
> >programmable resistors?
> > https://www.sciencedaily.com/releases/2022/07/220728142923.htm
>
> One real-world problem is, how do you make a wide-range bipolar
> reasonably-wideband accurate low-noise isolated resistor?

motorized potentiometer? :P

John Larkin wrote:
> On Fri, 29 Jul 2022 14:50:31 -0400, Phil Hobbs
> <pcdhSpamMeSenseless@electrooptical.net> wrote:
>
>> John Larkin wrote:
>>> On Fri, 29 Jul 2022 11:34:18 -0400, Phil Hobbs
>>> <pcdhSpamMeSenseless@electrooptical.net> wrote:
>>>
>>>> jlarkin@highlandsniptechnology.com wrote:
>>>>> On Fri, 29 Jul 2022 06:17:01 GMT, Jan Panteltje
>>>>> <pNaonStpealmtje@yahoo.com> wrote:
>>>>>
>>>>>> programmable resistors?
>>>>>> https://www.sciencedaily.com/releases/2022/07/220728142923.htm
>>>>>
>>>>> One real-world problem is, how do you make a wide-range bipolar
>>>>> reasonably-wideband accurate low-noise isolated
>>>>
>>>> wideband
>>>
>>> Kilohertz, to simulate RTDs mostly. A user might scan/mux RTDs and
>>> might mux the excitation too, so we want sub-millisecond response but
>>> not RF.
>>>
>>> Circuit puzzle: How do you make an electronic wide-range bipolar
>>> programmable resistor, say 0.1% accurate?
>>>
>>>>
>>>>> resistor?
>>>>>
>>>>> Some people do that with lots of resistors and relays, but electronic
>>>>> is more interesting.
>>>>>
>>>>
>>>> Interestingly, Murata will make custom laser-trimmed metal film resistor
>>>> arrays for pretty cheap. We're looking at using them in our next
>>>> generation variable-gain amplifier box.
>>
>> Probably a binary version of a resistor substitution box. Details
>> obviously depend a lot on the voltage range required.
>
> Oh, another requirement is that resistance changes be monotonic and
> glitch-free. An RTD simulator souldn't spike to 300C when it's
> supposed to go from 25.2 to 25.3. Relay switched resistors have that
> problem.

That's not so hard at kilohertz speeds--you can filter out the mux spikes.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

lørdag den 30. juli 2022 kl. 02.12.00 UTC+2 skrev Phil Hobbs:
> John Larkin wrote:
> > On Fri, 29 Jul 2022 14:50:31 -0400, Phil Hobbs
> > <pcdhSpamM...@electrooptical.net> wrote:
> >
> >> John Larkin wrote:
> >>> On Fri, 29 Jul 2022 11:34:18 -0400, Phil Hobbs
> >>> <pcdhSpamM...@electrooptical.net> wrote:
> >>>
> >>>> jla...@highlandsniptechnology.com wrote:
> >>>>> On Fri, 29 Jul 2022 06:17:01 GMT, Jan Panteltje
> >>>>> <pNaonSt...@yahoo.com> wrote:
> >>>>>
> >>>>>> programmable resistors?
> >>>>>> https://www.sciencedaily.com/releases/2022/07/220728142923.htm
> >>>>>
> >>>>> One real-world problem is, how do you make a wide-range bipolar
> >>>>> reasonably-wideband accurate low-noise isolated
> >>>>
> >>>> wideband
> >>>
> >>> Kilohertz, to simulate RTDs mostly. A user might scan/mux RTDs and
> >>> might mux the excitation too, so we want sub-millisecond response but
> >>> not RF.
> >>>
> >>> Circuit puzzle: How do you make an electronic wide-range bipolar
> >>> programmable resistor, say 0.1% accurate?
> >>>
> >>>>
> >>>>> resistor?
> >>>>>
> >>>>> Some people do that with lots of resistors and relays, but electronic
> >>>>> is more interesting.
> >>>>>
> >>>>
> >>>> Interestingly, Murata will make custom laser-trimmed metal film resistor
> >>>> arrays for pretty cheap. We're looking at using them in our next
> >>>> generation variable-gain amplifier box.
> >>
> >> Probably a binary version of a resistor substitution box. Details
> >> obviously depend a lot on the voltage range required.
> >
> > Oh, another requirement is that resistance changes be monotonic and
> > glitch-free. An RTD simulator souldn't spike to 300C when it's
> > supposed to go from 25.2 to 25.3. Relay switched resistors have that
> > problem.
> That's not so hard at kilohertz speeds--you can filter out the mux spikes..

with digital pots in audio it is called zipper noise, I believe some of them
use the trick of only changing gain in zero crossings

Lasse Langwadt Christensen wrote:
> lørdag den 30. juli 2022 kl. 02.12.00 UTC+2 skrev Phil Hobbs:
>> John Larkin wrote:
>>> On Fri, 29 Jul 2022 14:50:31 -0400, Phil Hobbs
>>> <pcdhSpamM...@electrooptical.net> wrote:
>>>
>>>> John Larkin wrote:
>>>>> On Fri, 29 Jul 2022 11:34:18 -0400, Phil Hobbs
>>>>> <pcdhSpamM...@electrooptical.net> wrote:
>>>>>
>>>>>> jla...@highlandsniptechnology.com wrote:
>>>>>>> On Fri, 29 Jul 2022 06:17:01 GMT, Jan Panteltje
>>>>>>> <pNaonSt...@yahoo.com> wrote:
>>>>>>>
>>>>>>>> programmable resistors?
>>>>>>>> https://www.sciencedaily.com/releases/2022/07/220728142923.htm
>>>>>>>
>>>>>>> One real-world problem is, how do you make a wide-range bipolar
>>>>>>> reasonably-wideband accurate low-noise isolated
>>>>>>
>>>>>> wideband
>>>>>
>>>>> Kilohertz, to simulate RTDs mostly. A user might scan/mux RTDs and
>>>>> might mux the excitation too, so we want sub-millisecond response but
>>>>> not RF.
>>>>>
>>>>> Circuit puzzle: How do you make an electronic wide-range bipolar
>>>>> programmable resistor, say 0.1% accurate?
>>>>>
>>>>>>
>>>>>>> resistor?
>>>>>>>
>>>>>>> Some people do that with lots of resistors and relays, but electronic
>>>>>>> is more interesting.
>>>>>>>
>>>>>>
>>>>>> Interestingly, Murata will make custom laser-trimmed metal film resistor
>>>>>> arrays for pretty cheap. We're looking at using them in our next
>>>>>> generation variable-gain amplifier box.
>>>>
>>>> Probably a binary version of a resistor substitution box. Details
>>>> obviously depend a lot on the voltage range required.
>>>
>>> Oh, another requirement is that resistance changes be monotonic and
>>> glitch-free. An RTD simulator souldn't spike to 300C when it's
>>> supposed to go from 25.2 to 25.3. Relay switched resistors have that
>>> problem.
>> That's not so hard at kilohertz speeds--you can filter out the mux spikes.
>
> with digital pots in audio it is called zipper noise, I believe some of them
> use the trick of only changing gain in zero crossings
>

For kilohertzy things you can use simulated inductors.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

On Sat, 30 Jul 2022 01:20:50 -0700 (PDT), Lasse Langwadt Christensen
<langwadt@fonz.dk> wrote:

>lørdag den 30. juli 2022 kl. 02.12.00 UTC+2 skrev Phil Hobbs:
>> John Larkin wrote:
>> > On Fri, 29 Jul 2022 14:50:31 -0400, Phil Hobbs
>> > <pcdhSpamM...@electrooptical.net> wrote:
>> >
>> >> John Larkin wrote:
>> >>> On Fri, 29 Jul 2022 11:34:18 -0400, Phil Hobbs
>> >>> <pcdhSpamM...@electrooptical.net> wrote:
>> >>>
>> >>>> jla...@highlandsniptechnology.com wrote:
>> >>>>> On Fri, 29 Jul 2022 06:17:01 GMT, Jan Panteltje
>> >>>>> <pNaonSt...@yahoo.com> wrote:
>> >>>>>
>> >>>>>> programmable resistors?
>> >>>>>> https://www.sciencedaily.com/releases/2022/07/220728142923.htm
>> >>>>>
>> >>>>> One real-world problem is, how do you make a wide-range bipolar
>> >>>>> reasonably-wideband accurate low-noise isolated
>> >>>>
>> >>>> wideband
>> >>>
>> >>> Kilohertz, to simulate RTDs mostly. A user might scan/mux RTDs and
>> >>> might mux the excitation too, so we want sub-millisecond response but
>> >>> not RF.
>> >>>
>> >>> Circuit puzzle: How do you make an electronic wide-range bipolar
>> >>> programmable resistor, say 0.1% accurate?
>> >>>
>> >>>>
>> >>>>> resistor?
>> >>>>>
>> >>>>> Some people do that with lots of resistors and relays, but electronic
>> >>>>> is more interesting.
>> >>>>>
>> >>>>
>> >>>> Interestingly, Murata will make custom laser-trimmed metal film resistor
>> >>>> arrays for pretty cheap. We're looking at using them in our next
>> >>>> generation variable-gain amplifier box.
>> >>
>> >> Probably a binary version of a resistor substitution box. Details
>> >> obviously depend a lot on the voltage range required.
>> >
>> > Oh, another requirement is that resistance changes be monotonic and
>> > glitch-free. An RTD simulator souldn't spike to 300C when it's
>> > supposed to go from 25.2 to 25.3. Relay switched resistors have that
>> > problem.
>> That's not so hard at kilohertz speeds--you can filter out the mux spikes.
>
>with digital pots in audio it is called zipper noise, I believe some of them
>use the trick of only changing gain in zero crossings

A resistor simulator that does RTDs can't do that. And can't, as far
as I can figure, filter out relay transitions.

John Larkin wrote:
> On Sat, 30 Jul 2022 01:20:50 -0700 (PDT), Lasse Langwadt Christensen
> <langwadt@fonz.dk> wrote:
>
>> lørdag den 30. juli 2022 kl. 02.12.00 UTC+2 skrev Phil Hobbs:
>>> John Larkin wrote:
>>>> On Fri, 29 Jul 2022 14:50:31 -0400, Phil Hobbs
>>>> <pcdhSpamM...@electrooptical.net> wrote:
>>>>
>>>>> John Larkin wrote:
>>>>>> On Fri, 29 Jul 2022 11:34:18 -0400, Phil Hobbs
>>>>>> <pcdhSpamM...@electrooptical.net> wrote:
>>>>>>
>>>>>>> jla...@highlandsniptechnology.com wrote:
>>>>>>>> On Fri, 29 Jul 2022 06:17:01 GMT, Jan Panteltje
>>>>>>>> <pNaonSt...@yahoo.com> wrote:
>>>>>>>>
>>>>>>>>> programmable resistors?
>>>>>>>>> https://www.sciencedaily.com/releases/2022/07/220728142923.htm
>>>>>>>>
>>>>>>>> One real-world problem is, how do you make a wide-range bipolar
>>>>>>>> reasonably-wideband accurate low-noise isolated
>>>>>>>
>>>>>>> wideband
>>>>>>
>>>>>> Kilohertz, to simulate RTDs mostly. A user might scan/mux RTDs and
>>>>>> might mux the excitation too, so we want sub-millisecond response but
>>>>>> not RF.
>>>>>>
>>>>>> Circuit puzzle: How do you make an electronic wide-range bipolar
>>>>>> programmable resistor, say 0.1% accurate?
>>>>>>
>>>>>>>
>>>>>>>> resistor?
>>>>>>>>
>>>>>>>> Some people do that with lots of resistors and relays, but electronic
>>>>>>>> is more interesting.
>>>>>>>>
>>>>>>>
>>>>>>> Interestingly, Murata will make custom laser-trimmed metal film resistor
>>>>>>> arrays for pretty cheap. We're looking at using them in our next
>>>>>>> generation variable-gain amplifier box.
>>>>>
>>>>> Probably a binary version of a resistor substitution box. Details
>>>>> obviously depend a lot on the voltage range required.
>>>>
>>>> Oh, another requirement is that resistance changes be monotonic and
>>>> glitch-free. An RTD simulator souldn't spike to 300C when it's
>>>> supposed to go from 25.2 to 25.3. Relay switched resistors have that
>>>> problem.
>>> That's not so hard at kilohertz speeds--you can filter out the mux spikes.
>>
>> with digital pots in audio it is called zipper noise, I believe some of them
>> use the trick of only changing gain in zero crossings
>
> A resistor simulator that does RTDs can't do that. And can't, as far
> as I can figure, filter out relay transitions.
>

Not if it has to look like a resistor at all frequencies, right. But a
kilohertzy device could look like a high-Z LC lowpass for nanosecond
spikes. It would need a floating simulated inductor.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com