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low cost isolation amplifier

Started by Unknown November 18, 2021
https://www.mouser.com/ProductDetail/Texas-Instruments/ISO120SG?qs=rNOSrj6uCs17dA0jO5%2FyAw%3D%3D



-- 

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 11/17/2021 11:19 PM, jlarkin@highlandsniptechnology.com wrote:
> > https://www.mouser.com/ProductDetail/Texas-Instruments/ISO120SG?qs=rNOSrj6uCs17dA0jO5%2FyAw%3D%3D > > >
They had to pay the burglars to snatch some out of the Smithsonian so they could put them back on the shelf
On Thu, 18 Nov 2021 00:00:46 -0500, bitrex <user@example.net> wrote:

>On 11/17/2021 11:19 PM, jlarkin@highlandsniptechnology.com wrote: >> >> https://www.mouser.com/ProductDetail/Texas-Instruments/ISO120SG?qs=rNOSrj6uCs17dA0jO5%2FyAw%3D%3D >> >> >> > >They had to pay the burglars to snatch some out of the Smithsonian so >they could put them back on the shelf
But I really need a low cost isolation amplifier. Looks like roughly $3 each. SiLabs has a three channel isolated ADC that is interesting, if I can figure out the actual throughput rate. Si8902. -- 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 (Wed, 17 Nov 2021 20:19:54 -0800) it happened
jlarkin@highlandsniptechnology.com wrote in
<02lbpgt8a1m6t56vfnv8lcqpvnotmj7rhk@4ax.com>:

Nice to have it all in that chip,
but the modulation - demodulation is always a bit .. Not Needed?
I remember back in the seventies using optocouplers for audio and a bit higher
frequencies, there was a chip for that too, no idea what the type number was.
May still have one somewhere,


Jan Panteltje wrote:
> On a sunny day (Wed, 17 Nov 2021 20:19:54 -0800) it happened > jlarkin@highlandsniptechnology.com wrote in > <02lbpgt8a1m6t56vfnv8lcqpvnotmj7rhk@4ax.com>: > > Nice to have it all in that chip, > but the modulation - demodulation is always a bit .. Not Needed? > I remember back in the seventies using optocouplers for audio and a bit higher > frequencies, there was a chip for that too, no idea what the type number was. > May still have one somewhere, > >
TI used to make the (iirc) TIL311, which had a LED and two photodiodes, all mutually isolated. You used one PD to servo the LED brightness, and used the other one as the output. 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
Am 18.11.21 um 05:19 schrieb jlarkin@highlandsniptechnology.com:
> > https://www.mouser.com/ProductDetail/Texas-Instruments/ISO120SG?qs=rNOSrj6uCs17dA0jO5%2FyAw%3D%3D
I had one of these, internally capacitively coupled, underpopulated DIL-28 with just 8 pins or so, 20 years ago. It had to be statically shielded, or a 400V AC line 10 cm above it would drive it nuts. ISO-12? could fit. cheers, Gerhard
On 11/18/2021 12:28 AM, jlarkin@highlandsniptechnology.com wrote:
> On Thu, 18 Nov 2021 00:00:46 -0500, bitrex <user@example.net> wrote: > >> On 11/17/2021 11:19 PM, jlarkin@highlandsniptechnology.com wrote: >>> >>> https://www.mouser.com/ProductDetail/Texas-Instruments/ISO120SG?qs=rNOSrj6uCs17dA0jO5%2FyAw%3D%3D >>> >>> >>> >> >> They had to pay the burglars to snatch some out of the Smithsonian so >> they could put them back on the shelf > > But I really need a low cost isolation amplifier. > > Looks like roughly $3 each. SiLabs has a three channel isolated ADC > that is interesting, if I can figure out the actual throughput rate. > Si8902. >
I haven't used SiLabs isolated ADCs but I have used their isolated gate drivers, they're great value parts! You can push several MHz across the isolation barrier into a load not a problem. Only downside is a bit less stand-off voltage than the equivalent ADI parts, and when they say "moisture sensitive" they really mean it, they'll go bad quick if you don't mount them after being exposed to non humidity-controlled environment. The ADI parts say similar on the pack but in practice it never happened to me while prototyping.
On 11/18/2021 7:42 AM, bitrex wrote:
> On 11/18/2021 12:28 AM, jlarkin@highlandsniptechnology.com wrote: >> On Thu, 18 Nov 2021 00:00:46 -0500, bitrex <user@example.net> wrote: >> >>> On 11/17/2021 11:19 PM, jlarkin@highlandsniptechnology.com wrote: >>>> >>>> https://www.mouser.com/ProductDetail/Texas-Instruments/ISO120SG?qs=rNOSrj6uCs17dA0jO5%2FyAw%3D%3D >>>> >>>> >>>> >>>> >>> >>> They had to pay the burglars to snatch some out of the Smithsonian so >>> they could put them back on the shelf >> >> But I really need a low cost isolation amplifier. >> >> Looks like roughly $3 each. SiLabs has a three channel isolated ADC >> that is interesting, if I can figure out the actual throughput rate. >> Si8902. >> > > I haven't used SiLabs isolated ADCs but I have used their isolated gate > drivers, they're great value parts! You can push several MHz across the > isolation barrier into a load not a problem. Only downside is a bit less > stand-off voltage than the equivalent ADI parts, and when they say > "moisture sensitive" they really mean it, they'll go bad quick if you > don't mount them after being exposed to non humidity-controlled > environment.
Or rather, they'll go bad when you try to mount them after too long in that environment.
bitrex <user@example.net> wrote:
> On 11/17/2021 11:19 PM, jlarkin@highlandsniptechnology.com wrote: >> >> https://www.mouser.com/ProductDetail/Texas-Instruments/ISO120SG?qs=rNOSrj6uCs17dA0jO5%2FyAw%3D%3D >> >> >> > > They had to pay the burglars to snatch some out of the Smithsonian so > they could put them back on the shelf
They come in a tube of 9, and they have 8 on stock. So probably at some time someone ordered one, they ordered a tube of 9 from TI and put the remaining 8 on stock. :-)
Phil Hobbs wrote:
> Jan Panteltje wrote: >> On a sunny day (Wed, 17 Nov 2021 20:19:54 -0800) it happened >> jlarkin@highlandsniptechnology.com wrote in >> <02lbpgt8a1m6t56vfnv8lcqpvnotmj7rhk@4ax.com>: >> >> Nice to have it all in that chip, but the modulation - demodulation >> is always a bit .. Not Needed? I remember back in the seventies >> using optocouplers for audio and a bit higher frequencies, there >> was a chip for that too, no idea what the type number was. May >> still have one somewhere, >> >> > > TI used to make the (iirc) TIL311,
TIL300, it was.
> which had a LED and two photodiodes, all mutually isolated. You used > one PD to servo the LED brightness, and used the other one as the > output. > > 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