On a sunny day (Tue, 12 Oct 2021 09:42:40 -0700) it happened
jlarkin@highlandsniptechnology.com wrote in
<rjebmgpp4mmfdr232b3e2ifb35psoshhtb@4ax.com>:

>On Tue, 12 Oct 2021 16:23:49 GMT, Jan Panteltje
><pNaonStpealmtje@yahoo.com> wrote:
>
>>On a sunny day (Tue, 12 Oct 2021 08:04:35 -0700) it happened
>>jlarkin@highlandsniptechnology.com wrote in
>><5g8bmgl9sulcoahfvpcomiueu2s7os90aj@4ax.com>:
>>
>>>On Sun, 10 Oct 2021 16:01:53 -0700, John Larkin
>>><jlarkin@highland_atwork_technology.com> wrote:
>>>
>>>>On Sun, 10 Oct 2021 15:10:39 -0700 (PDT), Jim MacArthur
>>>><jimbmacarthur@gmail.com> wrote:
>>>>
>>>>>Ah, the DAC1220.  I see the silicon is up to rev "E".  Those earlier revs sure were stinkers.  Limit cycles.  Regions of
>>>>>non-monotonic behavior.  And every few months, every tenth-ish chip would "rail" by going to its positive max voltage and
>>>>>staying
>>>>>there until it was power-cycled.  Hilarious, especially if you're a researcher whose particle just got sprung from a trap
>>>>>(where it
>>>>>had been held for months) when one of the electrodes went nuts.  TI acknowledged all of the faults and kept on plugging.  I
>>>>>haven't used the chip in a decade, so maybe it's okay now.
>>>>
>>>>We've used about 400 in the last few years and I haven't heard of any
>>>>problems. Maybe they fixed it.
>>>
>>>My test people report no problems with it so far.
>>>
>>>It's used in a 8-channel isolated thermocouple simulator.
>>>
>>>https://www.dropbox.com/s/ybcnzqbb3kdpe62/P470_DAC.jpg?raw=1
>>>
>>>http://www.highlandtechnology.com/DSS/P470DS.shtml
>>
>>Who buys a 'thermocouple simulator' ?
>>You can get a real thermocouple for peanuts,
>>and open and short takes a second.
>>Heating and cooling one is not that hard either, at least for me...
>>The Matrix???
>> 
>
>People testing aircraft systems mostly. They want to automate testing,
>without people dipping thermouples into buckets of water.

Water? I fixed some to my cryo cooler :-)
 http://panteltje.com//pub/cryo/not_a_dewar_2_img_2869.jpg

Its cold in space.

On Tue, 12 Oct 2021 16:23:49 GMT, Jan Panteltje
<pNaonStpealmtje@yahoo.com> wrote:

>On a sunny day (Tue, 12 Oct 2021 08:04:35 -0700) it happened
>jlarkin@highlandsniptechnology.com wrote in
><5g8bmgl9sulcoahfvpcomiueu2s7os90aj@4ax.com>:
>
>>On Sun, 10 Oct 2021 16:01:53 -0700, John Larkin
>><jlarkin@highland_atwork_technology.com> wrote:
>>
>>>On Sun, 10 Oct 2021 15:10:39 -0700 (PDT), Jim MacArthur
>>><jimbmacarthur@gmail.com> wrote:
>>>
>>>>Ah, the DAC1220.  I see the silicon is up to rev "E".  Those earlier revs sure were stinkers.  Limit cycles.  Regions of
>>>>non-monotonic behavior.  And every few months, every tenth-ish chip would "rail" by going to its positive max voltage and staying
>>>>there until it was power-cycled.  Hilarious, especially if you're a researcher whose particle just got sprung from a trap (where it
>>>>had been held for months) when one of the electrodes went nuts.  TI acknowledged all of the faults and kept on plugging.  I
>>>>haven't used the chip in a decade, so maybe it's okay now.
>>>
>>>We've used about 400 in the last few years and I haven't heard of any
>>>problems. Maybe they fixed it.
>>
>>My test people report no problems with it so far.
>>
>>It's used in a 8-channel isolated thermocouple simulator.
>>
>>https://www.dropbox.com/s/ybcnzqbb3kdpe62/P470_DAC.jpg?raw=1
>>
>>http://www.highlandtechnology.com/DSS/P470DS.shtml
>
>Who buys a 'thermocouple simulator' ?
>You can get a real thermocouple for peanuts,
>and open and short takes a second.
>Heating and cooling one is not that hard either, at least for me...
>The Matrix???
> 

People testing aircraft systems mostly. They want to automate testing,
without people dipping thermouples into buckets of water.



-- 

Father Brown's figure remained quite dark and still; 
but in that instant he had lost his head. His head was
always most valuable when he had lost it.

On a sunny day (Tue, 12 Oct 2021 08:04:35 -0700) it happened
jlarkin@highlandsniptechnology.com wrote in
<5g8bmgl9sulcoahfvpcomiueu2s7os90aj@4ax.com>:

>On Sun, 10 Oct 2021 16:01:53 -0700, John Larkin
><jlarkin@highland_atwork_technology.com> wrote:
>
>>On Sun, 10 Oct 2021 15:10:39 -0700 (PDT), Jim MacArthur
>><jimbmacarthur@gmail.com> wrote:
>>
>>>Ah, the DAC1220.  I see the silicon is up to rev "E".  Those earlier revs sure were stinkers.  Limit cycles.  Regions of
>>>non-monotonic behavior.  And every few months, every tenth-ish chip would "rail" by going to its positive max voltage and staying
>>>there until it was power-cycled.  Hilarious, especially if you're a researcher whose particle just got sprung from a trap (where it
>>>had been held for months) when one of the electrodes went nuts.  TI acknowledged all of the faults and kept on plugging.  I
>>>haven't used the chip in a decade, so maybe it's okay now.
>>
>>We've used about 400 in the last few years and I haven't heard of any
>>problems. Maybe they fixed it.
>
>My test people report no problems with it so far.
>
>It's used in a 8-channel isolated thermocouple simulator.
>
>https://www.dropbox.com/s/ybcnzqbb3kdpe62/P470_DAC.jpg?raw=1
>
>http://www.highlandtechnology.com/DSS/P470DS.shtml

Who buys a 'thermocouple simulator' ?
You can get a real thermocouple for peanuts,
and open and short takes a second.
Heating and cooling one is not that hard either, at least for me...
The Matrix???

On Sun, 10 Oct 2021 16:01:53 -0700, John Larkin
<jlarkin@highland_atwork_technology.com> wrote:

>On Sun, 10 Oct 2021 15:10:39 -0700 (PDT), Jim MacArthur
><jimbmacarthur@gmail.com> wrote:
>
>>Ah, the DAC1220.  I see the silicon is up to rev "E".  Those earlier revs sure were stinkers.  Limit cycles.  Regions of non-monotonic behavior.  And every few months, every tenth-ish chip would "rail" by going to its positive max voltage and staying there until it was power-cycled.  Hilarious, especially if you're a researcher whose particle just got sprung from a trap (where it had been held for months) when one of the electrodes went nuts.  TI acknowledged all of the faults and kept on plugging.  I haven't used the chip in a decade, so maybe it's okay now.
>
>We've used about 400 in the last few years and I haven't heard of any
>problems. Maybe they fixed it.

My test people report no problems with it so far.

It's used in a 8-channel isolated thermocouple simulator.

https://www.dropbox.com/s/ybcnzqbb3kdpe62/P470_DAC.jpg?raw=1

http://www.highlandtechnology.com/DSS/P470DS.shtml




-- 

Father Brown's figure remained quite dark and still; 
but in that instant he had lost his head. His head was
always most valuable when he had lost it.

On Monday, October 11, 2021 at 11:06:15 PM UTC+11, jla...@highlandsniptechnology.com wrote:
> On Sun, 10 Oct 2021 07:46:10 +0100, piglet <erichp...@hotmail.com> 
> wrote:
> >On 09/10/2021 7:45 pm, jla...@highlandsniptechnology.com wrote: 
> >> On Sat, 09 Oct 2021 17:37:32 GMT, Jan Panteltje <pNaonSt...@yahoo.com> wrote:  
> >>> On a sunny day (Sat, 09 Oct 2021 08:05:34 -0700) it happened jla...@highlandsniptechnology.com wrote in  <vfb3mg51v2blgg9c8...@4ax.com>: 

> That is one of the potential bugs. Some opamps would go nuts, not from 
> the load as much from the charge injection spike from the analog 
> switch. That DG333 claims 1 pC, 10 pC, or 30 pC on various parts of 
> the data sheet. 

The "1pC" charge injection claim is on the first page of the data sheet.

The "10pC" maximum charge injection is on page 3 for specific conditions.

There as graph of charge injection as a function of "source voltage"  on page 5. running from zero at -15V down to -20pC at -10V before rising back to zero again at 0V and going up from there to about 30pC at about 13V where it sticks until you get up to 15V.

Somebody who actually did electronic design might try to work out what was going on and try to fudge the circuit so that there wasn't much charge injection in their particular application.

There's a device level circuit diagram of the part on page 2 of the data sheet - thinking about what those parts might be expected to do could be a useful exercise.

Bitching that the data sheet didn't spoon-feed you the data you need is less useful.

> Gotta fix that.

By taking over Vishay and getting them to give you the kind of data sheet you'd like?

-- 
Bill Sloman, Sydney

> They were going to the ballpark for the game but her SO broke his 
> foot, so they had to watch it on their enormous OLED TV. 
> 
> Incidentally, I want to buy Mo a new TV. The oleds look fabulous; do 
> the pixels wear out?
> -- 
> 
(signalling my day job..)
Hi John
I would not hesitate getting an OLED TV
from either LG or Sony (the two major
brands who've been releasing OLEDs for 
many years.)  OLED & LCD TVs 
have generally become more reliable. 
LG & Sony are 2 of the higher-predicted
reliability brands for TVs (with edge
to Sony) - per survey researcher analyses. 
One of our recent surveys, my colleagues 
in survey research reported 98%+ of all
TVs bought in the last 5 years are still
operating OK. Of those which did break,
#1 issue at ~ 30% was, TV wouldn't turn
on. #2 at ~20% was lost picture. #3 at 
~10% was distorted/poor picture quality.  
#4 issue at ~10% was bad pixels. I know
these problems may sound general, but 
this is the kind of survey results I
get. Cheers, Rich S.

On Sun, 10 Oct 2021 15:10:39 -0700 (PDT), Jim MacArthur
<jimbmacarthur@gmail.com> wrote:

>Ah, the DAC1220.  I see the silicon is up to rev "E".  Those earlier revs sure were stinkers.  Limit cycles.  Regions of non-monotonic behavior.  And every few months, every tenth-ish chip would "rail" by going to its positive max voltage and staying there until it was power-cycled.  Hilarious, especially if you're a researcher whose particle just got sprung from a trap (where it had been held for months) when one of the electrodes went nuts.  TI acknowledged all of the faults and kept on plugging.  I haven't used the chip in a decade, so maybe it's okay now.

We've used about 400 in the last few years and I haven't heard of any
problems. Maybe they fixed it.



-- 

If a man will begin with certainties, he shall end with doubts, 
but if he will be content to begin with doubts he shall end in certainties.
Francis Bacon

Ah, the DAC1220.  I see the silicon is up to rev "E".  Those earlier revs sure were stinkers.  Limit cycles.  Regions of non-monotonic behavior.  And every few months, every tenth-ish chip would "rail" by going to its positive max voltage and staying there until it was power-cycled.  Hilarious, especially if you're a researcher whose particle just got sprung from a trap (where it had been held for months) when one of the electrodes went nuts.  TI acknowledged all of the faults and kept on plugging.  I haven't used the chip in a decade, so maybe it's okay now.

On Sun, 10 Oct 2021 21:02:38 +0100, piglet <erichpwagner@hotmail.com>
wrote:

>On 10/10/2021 5:13 pm, jlarkin@highlandsniptechnology.com wrote:
>> The possible bugs are:
>> 
>> Charge injection from the DG331 back into the OPA197. I've seen opamps
>> go crazy for many microseconds in similar cases.
>> 
>
>Yes, I did raise that question about ten hours before, didn't you see it?
>
>piglet

Yes, I responded clarifying that charge injection is a concern.
Lately, some of my posts don't seem to show up.

-- 

If a man will begin with certainties, he shall end with doubts, 
but if he will be content to begin with doubts he shall end in certainties.
Francis Bacon