Should be easy to compare - sand down both the cheapo and a legit one (with a similar datecode) with fine sandpaper, clean with isoprop and shove under an optical microscope - you can then tell how similar/dissimilar the dies are, you don't even have to look for markings or anything super legible, or even sand them to the same metal layer.
Clones tend to be vastly different - different technology node, architecture, die size, etc. - that's because they are generally functional clones, not mask clones.
I have done this a bunch of different times, mostly to resolve sourcing disputes. Dissolving in boiling sulphuric acid/nitric acid will make quick work of most epoxy packaging
IMO, I have mostly seen mislabeling, rebinning, and passing off obvious QC rejects.
> Dissolving in boiling sulphuric acid/nitric acid will make quick work of most epoxy packaging
That's the better method of course (results wise), but it's not nearly as accessible, hence my recent evangelism of the virtues of 2000 grit sandpaper.
I prefer Japanese sharpening stones or those DMT diamond whetstones. It’s relative easy to 3d print a jig that converts a woodworking honing guide into an IC holder and you get a feel for how many passes to do very quickly before slowing down and checking each pass.
There was a sandpaper expert in that company associated with sour-tasting fruit which shall not be named. I believe you guys have met, though I think by that time he already pivoted to making the perfect cheesecake.
I like it. I've used sandpaper to solve some interesting problems in the past as well with great success. I suspect we are only seeing the beginnings here in a trend of high-tech applications of fine grit paper.
I expect it's much easier to acquire fine sandpaper, yet my inner child yearns for laser decapping. (Or I suppose more than "decapping", depending on the depth.)
High power lasers are becoming more and more affordable. Laser ablation is definitely an option but you really want to have some proper fume extraction around that.
It may not even be a clone. As the author said, it could just as easily be production line items that were tested and found to be outside of spec tolerances and resold off-label.
Yes, though depending on the product line it may be binned into lower quality parts first. Remember though, the marginal cost of these chips is so small the packaging is usually more expensive than the silicon. They often get tested before the wafer is even sliced up so any waste is hardly worth mentioning until you get into modern processes with large error rates and huge chips like CPUs.
TI isn't patterning $10000 wafers at 3nm with massive chiplets and questionable yield, they are making mostly commodity ICs on cheaper processes - they can afford to discard rejects.
> These are cheap, relatively fast, and not particularly good. While they sport impressive-sounding 12- and 16-bit readouts, the effective number of bits (ENOB) is usually around 8 or 9.
I don't think that's quite accurate for reasonably modern MCUs. You can typically shake 10+ bits out of them, but you need to take a lot of precautions, such as providing very stable external reference voltage and shutting down unneeded subsystems of the chip.
They're still not as good as standalone ADCs, but they're at a point where you can actually use them for 90% of things that require an ADC.
In cases where you need more bits, there's a lot more that must go into the design, which is what gives me a pause about the article. There's nothing about the PSU the author is using or how he managed the MCU noise and RFI. So I don't know if the findings here are that these are knock-off devices with worse specs, or if his overhead LED lamp is causing a lot of interference.
I tested a few STM32F103 dev boards, using a Siglent SDM3055 multimeter and Siglent SPD330X power supply.
The chip has a 12bit SAR ADC. Layout and board design mattered a lot, but even the worst ones had 10 bits worth, and the best one had nearly 12 bits effective.
That was without doing too much on the software side, meaning the other modules weren't running, besides a single serial output. On the bad boards the serial affected it, but on the good board very little.
The paragraph ending with "Compare that with a microcontroller ADC with a fixed 3.3 V range: 9 ENOB steps are ~6 mV" also seems to insinuate that no MCU has an analog reference that's independent from the supply, which just isn't true at all. Hell, NXP has a few that have a built-in programmable reference.
I think you might both be right- the author may be thinking of lower cost MCUs only aiming for tolerable ADC performance, while you might be thinking of all MCUs, even higher cost.
The RP2350 has 9.2 ENOB on a 12 bit ADC. Sure, you might be able to decimate multiple samples to get more bits out of them, but the spec sheet supports the author's claim (https://www.raspberrypi.com/documentation/pico-sdk/hardware....). There are even lower cost MCUs like the CH32V003 that have even worse ADC performance.
On the other hand, some MCUs can definitely do 10+ bits, such as the STM32H7 line which gets 13+ ENOB from a 16 bit ADC. This is impressive, but the H7 MCUs are literally an order of magnitude more expensive than the RP2350, so they might not be something the author tinkers with much.
https://www.st.com/resource/en/application_note/dm00628458-g...
> So what’s going on with the cheap parts? My best guess is that these are either quite good copies, or failed parts that somehow made their way into the hobbyist supply chain.
The vast majority of counterfeit chips I've seen were from ghost shifts but IIRC TI fabs all their analog parts in house, I doubt they're ghost shift parts or failed QC.
Author here. I did consider this, as others have reported getting ADS1015 marked as ADS1115. If it were an ADS1015 the readout would be truncated at 12 bits. These parts definitely delivered 16 bits of readout.
I worry about the demo boards being radically different in terms of layout etc. Even if you're using the same interface and power supply, the PCB may be affecting performance.
Getting full spec performance out of an ADC requires having good layout power supply routing etc.
I would transplant the chips from PCB A to PCB B and vice versa. See if the performance follows the chip or the PCB.
Also check power consumption before / after board swaps. If they are fakes, that would be significantly different.
Analogy's datasheet is directly cribbed from TI's (see TI Fig. 7-7 / Analogy Fig. 22½, pg. 18).
This already passes my "run away screaming" threshold for trust, but a decapping would help me understand whether they've stolen the physical design (bad) or just cloned it (bad).
What's wrong with cloning a chip functionality-wise? This is basically how the industry has operated since its infancy, and what gave us jelly bean logic parts and transistors, x86 and the PC revolution, ...
(just talking about the cloning part here, not counterfeit markings or datasheet copyright infringement, or copying mask work)
There's nothing wrong with an open clone when everybody is acting in good faith. (In fact, "good faith" does not even necessarily mean "according to the letter of the law in $jurisdiction". Sometimes the law is an ass.)
However, there's nothing more toxic to an OEM than a vendor relationship founded on dishonesty. I know I shouldn't trust them, they know it too, and even if it seems advantageous at first I shouldn't be surprised when they turn on me.
Since these parts are being sold as genuine TI parts, I don't care whether the clone is physically faithful or just functionally faithful - I should treat it like it's poisonous.
If it's an open clone that can be reasonably distinguished from software side and from looking at the part and it doesn't violate IP laws other than software patents, no biggie.
Every clone of any sufficiently complex Thing will have subtle quirks and edge cases compared to the original and as long as I can work around them for only that specific clone model, that's easy.
But clones that have no way of determining if the part is a clone? That's bad to even exist because unscrupulous actors will go and repackage "legitimate clone" chips into faked originals if the price difference is big enough.
Interesting, most of the counterfeits that affect me (eg. FTDI, STM32 clones) have been just straight up clones developed from scratch, not excess inventory / ghost shifts / packaged rejects. I guess it might be a digital/mixed-signal split, with the two worlds having different issues?
(also interestingly the STM32 clones I've seen had stacked die flash because they didn't fab them in a technology that could also do flash, so you can easily tell the counterfeit from sanding down the package and looking for an extra set of bonding wires; it's also a cool place to access the internal flash bus if you wanna bypass some readout protection :) )
I remember the mess with FTDI clones back when I was still a hobbyist and buying stuff from eBay, but ever since I’ve started doing EE professionally I rarely run into anything that bad. You’re not going to make a clone Marvell processor for example, but I’ve run into several ghost shift runs from a distributor.
I don’t usually buy from electronics markets in Shenzhen either so that probably helps.
Buy in bulk from the Shenzhen markets and sellers will be pretty clear that you're getting a clone, and will give you samples of that specific clone so you can QA your product with them. (Some popular devices have multiple clone suppliers).
I now always buy clones where possible - whilst not all features are implemented and some specifications won't be met, the devices seem to match the original for reliability, and sometimes even come with their own cloned modded datasheet.
I'd like to know more about the world of ADCs. I've used the ADS1115 with success but only at very slow speeds.
On the current project we started with an MCP3208 via SPI. It did the job but only has 8 channels and it's slow (100K samples per sec).
To get something faster we switched to ADS7953. It has 16 channels and runs 10 times faster. It's somewhat more complex to code, and you can only get the highest sample rate if you scan the inputs in a predictable order. But it sure flies.
To me, these chips feel like cars. The ADS7953 is somewhat of a ferrari, whereas the MCP3208 feels like a Toyota, simple to use, unimpressive performance.
I'd love to know the industry background about how these varieties of ADC chips came to be and carved their own space in the world, and how widely they are used (millions? billions?).
> To get something faster we switched to ADS7953. It has 16 channels and runs 10 times faster.
I recall reading about a project at CERN to design a 12bit ADC chip that could sample at tens of GHz, maybe 50 or more.
I was perplexed at how they could achieve this.
Turned out it was the same we programmers do. Parallel processing.
They had taken a 12bit SAR unit which ran at like MHz rates, and just cloned it many times. They then had a large analog multiplexer in front to route the signal to the active ADC unit in a round-robin fashion.
That takes a lot of chip real-estate, and the analog muxer had to be carefully designed.
For a simpler approach to speed there is Flash ADCs[1], which kinda brute-force it.
For precision I know multi-slope ADCs[2] are often used.
Sadly I don't know much about the history, and would also love to learn more about it. Bound to be some fascinating stories there.
You can buy ADCs at over 100 GS/s (keysight, teledyne and tektronix make oscilloscopes using them), however typical ENOBs are more around 5 bits for these. For people interested in this stuff, I there is a video of someone taking apart one of the high speed keysight scopes (I think signal path is the YouTube channel?).
Keysight at least, has a fab where they make their own ADCs. Those are something like ENOB 6, 10 bit raw up to 120GHz and are used in their oscilloscopes but can also be purchased standalone.
Oscilloscopes also have a significant amount of additional front end conditioning, probe control, channel timing, and analysis software built into them. Most of the math functions on oscilloscopes use custom ASICs that work off the raw bits coming from the 120GHz digitizer which is non-trivial even just to receive. Calling it a plastic case around a digitizer is disingenuous.
> The ADS7953 is somewhat of a ferrari, whereas the MCP3208 feels like a Toyota, simple to use, unimpressive performance.
What about the AD9226? It only has a single channel but can do up to 65 MSa/s at 12 bits. I bought one as a module for around $12 on AliExpress to experiment with software decoding of analog video. I only run it at 20 MSa/s and only use 8 bits because, funnily enough, the limiting factor is the speed at which I could get the data into my laptop. I connected it to a Raspberry Pi Zero and use the SMI peripheral as described here: https://iosoft.blog/2020/07/16/raspberry-pi-smi/
Ultra high-speed ADCs are extremely ugly to handle with microcontrollers. That's mostly FPGA territory: toggle its pins, suck the data from the ADC and offer them on a friendly parallel bus for a microcontroller (USBC->Parallel interface from FTDI).
They need a lot of pins to be toggled. Otherwise they spit out no data.
And a lot of manual stuff means it's super DMA unfriendly. And you need DMA for high-speed stuff.
I thought I sucked at debouncing until I tried a rotary encoder that wasn’t like 10 for $4 on aliexpress. Lesson learned. Then I found out they sell a lot of decent related stuff at Micro center.
The price difference could be explained by LCSC purchasing in bulk directly from TI or similar and selling them at lower margins because their volumes are larger. I've seen "clone" chips sold at LCSC, but they're listed under a different brand (I can't recall one off memory unfortunately).
Why would it be bad for that price? Highly accurate ADCs are pretty easy to make, provided you don't need a high sample rate, thanks to the magic of signal processing. Delta-sigma ADCs, and ramp ADCs can use a single bit of digital input + some pattern hold circuitry to do incredibly accurate measurements, it's just they take some time.
If you want a flash ADC that can do 16 bit (and can do 16 bit at 100Mhz), however you'll have to probably mortgage your house.
Most companies have region-specific price lists. My Spotify subscription costs about 60% of what the same plan costs in the US (2200 HUF vs. 11 USD). In the electronics industry, everyone has a separate price list for China.
Btw. the western list price is just an indicative at-most number anyway. Even a small-sized project gets discounted prices when you start talking to a sales rep.
Well, I guess a whole-three-genuine-US-dollars is actually pretty expensive for an ADC, and that the person-in-charge-of-your-BOM in one of the countries that can actually still manufacture things can get one for way less than that.
Does it work? Well, does your design power up during factory testing, and then pass whatever things your rig (hope you made a few!) has in mind? Well, then, yes, in fact it does...
These numbers add up fast when you have dozens or hundreds of components on your board. A $3 part is often one of the most expensive items on a board! If you're trying to get something shipped to consumers for $20 each, with an enclosure, packaging, shipping, retail markup, and profit...that's a huge price disparity.
Also, and perhaps more importantly, the test rig is a lot simpler and a lot cheaper if you can generally trust manufacturer data. Sure, send off a few samples (likely prototypes with parts from Digikey instead of LCSC) to run extended testing in an environmental chamber with thermal imaging, build an endurance test rig that pushes the button once a second for four weeks to simulate once-daily use for years, whatever you want to do...but after that, if TI says it's good from -40 to +125, you're going to trust them on a lot of the edge cases.
Do 100% testing of the things you can test in-circuit if you can - power it up at room temperature and make sure it works once - but that doesn't mean you get the actual rated performance across all published environmental conditions.
> Single cycle readings defeat the point of sigma delta ADC setups.
The ADC's internal delta-sigma ADC takes a lot of samples at a much higher modulation frequency and presents them as a single output value.
You do not get the direct delta-sigma output from an ADC like this. The internal logic handles that for you. It's okay to take single samples of the output.
OP is using the chip with the data rate set to 8 samples per second.
Natively/internally, it runs at 860 samples per second, and you can configure it to provide that data at a lower sample rate at lower noise levels by averaging multiple readings together internally.
Digikey's markup is the issue.. most people in Asia buy from lcsc or agents, that can get parts 2-10 times cheaper.. In this case both parts are genuine just different batch/year/production location probably..
Ooh this is interesting! I've seen some big price differences between Digikey and LCSC at small volumes; not sure! You can also sometimes buy direct from TI.
Of interest from early in the article: I'm curious how these external ones compare to onboard, e.g. STM32's. Btw, the TI one listed is actually pretty simple to use in comparison. The ST integrated ones have more config and hardware considerations, e.g. complicated calibration procedures, external VREF (mentioned) etc. So, if you do app the config, is the integrated one as good?
The integrated ones usually have nice ways to integrate with timers and other onboard periphs.
There are a bunch of reasons but the primary reason is that good ADCs are made using a different mixed signal process than microcontrollers. MCU ADCs are capacitive charge-balancing successive-approximation type which limits their sensitivity and precision.
Standalone ADCs also eliminate significant sources of noise like temperature fluctuations and electronic noise (the digital logic on the chip often runs at less than 1Mhz for example)
Well, if you're trying to measure DC extremely accurately the old stuff is still golden. Multi-slope is the gold standard and no one will sell you one. Delta-sigma get most of the way there.
Err, the title isn't really correct. The genuine part is still only $4. This is a 60 cent knockoff. Not having done design in a while but still having a rough feeling for costs I was a bit confused.
Honestly: no one of the bigger players in the industry pays the prices you see on Digikey/Mouser/Farnell (with the exception maybe for prototyping stuff). Often you have direct delivery contracts with the vendors.
That the ADS1115 costs <$1 on LCSC means they buy millions from them every year. They are one of the biggest trustable players in Asia.
I have access to our internal STM32 pricing. You'd be shocked.
Yep people are mostly paying for the added inventory risk and labor when buying from distributors. Anyone with a big enough order to have their own wafer and the time to wait can get it a hell of a lot cheaper, especially for rarer parts that aren’t as popular.
One supplier I developed a relationship with showed us their internal numbers and it was $1,000-3,000 per wafer for 130nm-180nm nodes with a minimum order of 25 wafers. Once the part is designed and the mask is made, the cost is mostly just the setup plus whatever they want for the IP. The silicon itself is often cheaper than the packaging around it.
We buy low end STM32s in 10-100k quantities and pay shockingly low prices as you noted and that's through official channels. One of our other suppliers offered us some "compatible" parts that he "might be able to find" for about a quarter of the cost, but we declined.
I recalled a few years ago there were shockingly inexpensive MCUs at LCSC and similar far east vendors, but they were never heard before names, so I just checked again out of curiosity and here's a $0.05 one by Cypress.
They are huge step ahead: the upcoming CH32H417 has pretty much all PHYs integrated (!). For 10/100M Ethernet, USB-C 5GBbps and USB HS 480Mbps. That dramatically reduces the components needed to get that stuff running.
I also build a small robot with the ultra cheap CH32V003. That's a full fledged 48MHz microcontroller with 16kb flash and 2kb SRAM. Fun little thing.
If you are used to the ST HAL you will be able to work with them within 10 minutes. Their API style is similar.
Clones tend to be vastly different - different technology node, architecture, die size, etc. - that's because they are generally functional clones, not mask clones.
(also, as a general shoutout to the low tech sandpaper technique for exploratory work, here's a sanded down RP2350 thrown under a clapped out SEM: https://object.ceph-eu.hswaw.net/q3k-personal/484e7b33dbdbd9... https://object.ceph-eu.hswaw.net/q3k-personal/3290eef9b6b9ad... )
IMO, I have mostly seen mislabeling, rebinning, and passing off obvious QC rejects.
example from many years ago: https://www.youtube.com/watch?v=e6DfBuPwAAA
That's the better method of course (results wise), but it's not nearly as accessible, hence my recent evangelism of the virtues of 2000 grit sandpaper.
https://phillipscorp.com/india/phillipsgrinding/phillips-sur...
All you need is a serial port and some G-codes.
You could still compare the internal structure of the package and bonding, but the die itself is mostly destroyed.
Discarded things tend to get lost. Lost things tend not stay in the Anduin forever.
I'll have to put that on a warning label near our non-conforming-product containment shelf!
1. https://righto.com
I don't think that's quite accurate for reasonably modern MCUs. You can typically shake 10+ bits out of them, but you need to take a lot of precautions, such as providing very stable external reference voltage and shutting down unneeded subsystems of the chip.
They're still not as good as standalone ADCs, but they're at a point where you can actually use them for 90% of things that require an ADC.
In cases where you need more bits, there's a lot more that must go into the design, which is what gives me a pause about the article. There's nothing about the PSU the author is using or how he managed the MCU noise and RFI. So I don't know if the findings here are that these are knock-off devices with worse specs, or if his overhead LED lamp is causing a lot of interference.
The chip has a 12bit SAR ADC. Layout and board design mattered a lot, but even the worst ones had 10 bits worth, and the best one had nearly 12 bits effective.
That was without doing too much on the software side, meaning the other modules weren't running, besides a single serial output. On the bad boards the serial affected it, but on the good board very little.
The paragraph ending with "Compare that with a microcontroller ADC with a fixed 3.3 V range: 9 ENOB steps are ~6 mV" also seems to insinuate that no MCU has an analog reference that's independent from the supply, which just isn't true at all. Hell, NXP has a few that have a built-in programmable reference.
The RP2350 has 9.2 ENOB on a 12 bit ADC. Sure, you might be able to decimate multiple samples to get more bits out of them, but the spec sheet supports the author's claim (https://www.raspberrypi.com/documentation/pico-sdk/hardware....). There are even lower cost MCUs like the CH32V003 that have even worse ADC performance.
On the other hand, some MCUs can definitely do 10+ bits, such as the STM32H7 line which gets 13+ ENOB from a 16 bit ADC. This is impressive, but the H7 MCUs are literally an order of magnitude more expensive than the RP2350, so they might not be something the author tinkers with much. https://www.st.com/resource/en/application_note/dm00628458-g...
The vast majority of counterfeit chips I've seen were from ghost shifts but IIRC TI fabs all their analog parts in house, I doubt they're ghost shift parts or failed QC.
I think its probably a relabeled ADS1015.
Getting full spec performance out of an ADC requires having good layout power supply routing etc.
I would transplant the chips from PCB A to PCB B and vice versa. See if the performance follows the chip or the PCB.
Also check power consumption before / after board swaps. If they are fakes, that would be significantly different.
Many of these Dev boards are not produced with as much care or knowledge as the chip design itself.
Analogy: https://datasheet.lcsc.com/lcsc/2302211830_analogysemi-ADX11...
TI: https://www.ti.com/lit/ds/symlink/ads1115.pdf
Analogy's datasheet is directly cribbed from TI's (see TI Fig. 7-7 / Analogy Fig. 22½, pg. 18).
This already passes my "run away screaming" threshold for trust, but a decapping would help me understand whether they've stolen the physical design (bad) or just cloned it (bad).
See also: https://community.element14.com/members-area/f/forum/53365/n...
What's wrong with cloning a chip functionality-wise? This is basically how the industry has operated since its infancy, and what gave us jelly bean logic parts and transistors, x86 and the PC revolution, ...
(just talking about the cloning part here, not counterfeit markings or datasheet copyright infringement, or copying mask work)
However, there's nothing more toxic to an OEM than a vendor relationship founded on dishonesty. I know I shouldn't trust them, they know it too, and even if it seems advantageous at first I shouldn't be surprised when they turn on me.
Since these parts are being sold as genuine TI parts, I don't care whether the clone is physically faithful or just functionally faithful - I should treat it like it's poisonous.
Every clone of any sufficiently complex Thing will have subtle quirks and edge cases compared to the original and as long as I can work around them for only that specific clone model, that's easy.
But clones that have no way of determining if the part is a clone? That's bad to even exist because unscrupulous actors will go and repackage "legitimate clone" chips into faked originals if the price difference is big enough.
(also interestingly the STM32 clones I've seen had stacked die flash because they didn't fab them in a technology that could also do flash, so you can easily tell the counterfeit from sanding down the package and looking for an extra set of bonding wires; it's also a cool place to access the internal flash bus if you wanna bypass some readout protection :) )
I don’t usually buy from electronics markets in Shenzhen either so that probably helps.
I now always buy clones where possible - whilst not all features are implemented and some specifications won't be met, the devices seem to match the original for reliability, and sometimes even come with their own cloned modded datasheet.
On the current project we started with an MCP3208 via SPI. It did the job but only has 8 channels and it's slow (100K samples per sec).
To get something faster we switched to ADS7953. It has 16 channels and runs 10 times faster. It's somewhat more complex to code, and you can only get the highest sample rate if you scan the inputs in a predictable order. But it sure flies.
To me, these chips feel like cars. The ADS7953 is somewhat of a ferrari, whereas the MCP3208 feels like a Toyota, simple to use, unimpressive performance.
I'd love to know the industry background about how these varieties of ADC chips came to be and carved their own space in the world, and how widely they are used (millions? billions?).
I recall reading about a project at CERN to design a 12bit ADC chip that could sample at tens of GHz, maybe 50 or more.
I was perplexed at how they could achieve this.
Turned out it was the same we programmers do. Parallel processing.
They had taken a 12bit SAR unit which ran at like MHz rates, and just cloned it many times. They then had a large analog multiplexer in front to route the signal to the active ADC unit in a round-robin fashion.
That takes a lot of chip real-estate, and the analog muxer had to be carefully designed.
For a simpler approach to speed there is Flash ADCs[1], which kinda brute-force it.
For precision I know multi-slope ADCs[2] are often used.
Sadly I don't know much about the history, and would also love to learn more about it. Bound to be some fascinating stories there.
[1]: https://en.wikipedia.org/wiki/Flash_ADC
[2]: https://www.analog.com/media/en/training-seminars/tutorials/...
Unfortunately this isn't the case - the company designing the plastic case and buttons gets the lions share of the money.
Oscilloscopes also have a significant amount of additional front end conditioning, probe control, channel timing, and analysis software built into them. Most of the math functions on oscilloscopes use custom ASICs that work off the raw bits coming from the 120GHz digitizer which is non-trivial even just to receive. Calling it a plastic case around a digitizer is disingenuous.
What about the AD9226? It only has a single channel but can do up to 65 MSa/s at 12 bits. I bought one as a module for around $12 on AliExpress to experiment with software decoding of analog video. I only run it at 20 MSa/s and only use 8 bits because, funnily enough, the limiting factor is the speed at which I could get the data into my laptop. I connected it to a Raspberry Pi Zero and use the SMI peripheral as described here: https://iosoft.blog/2020/07/16/raspberry-pi-smi/
They need a lot of pins to be toggled. Otherwise they spit out no data.
And a lot of manual stuff means it's super DMA unfriendly. And you need DMA for high-speed stuff.
If you want a flash ADC that can do 16 bit (and can do 16 bit at 100Mhz), however you'll have to probably mortgage your house.
Btw. the western list price is just an indicative at-most number anyway. Even a small-sized project gets discounted prices when you start talking to a sales rep.
Does it work? Well, does your design power up during factory testing, and then pass whatever things your rig (hope you made a few!) has in mind? Well, then, yes, in fact it does...
Also, and perhaps more importantly, the test rig is a lot simpler and a lot cheaper if you can generally trust manufacturer data. Sure, send off a few samples (likely prototypes with parts from Digikey instead of LCSC) to run extended testing in an environmental chamber with thermal imaging, build an endurance test rig that pushes the button once a second for four weeks to simulate once-daily use for years, whatever you want to do...but after that, if TI says it's good from -40 to +125, you're going to trust them on a lot of the edge cases.
Do 100% testing of the things you can test in-circuit if you can - power it up at room temperature and make sure it works once - but that doesn't mean you get the actual rated performance across all published environmental conditions.
Single cycle readings defeat the point of sigma delta ADC setups.
You're taking many high noise samples and averaging them over time to get a better picture of the average voltage.
The ADC's internal delta-sigma ADC takes a lot of samples at a much higher modulation frequency and presents them as a single output value.
You do not get the direct delta-sigma output from an ADC like this. The internal logic handles that for you. It's okay to take single samples of the output.
Natively/internally, it runs at 860 samples per second, and you can configure it to provide that data at a lower sample rate at lower noise levels by averaging multiple readings together internally.
Of interest from early in the article: I'm curious how these external ones compare to onboard, e.g. STM32's. Btw, the TI one listed is actually pretty simple to use in comparison. The ST integrated ones have more config and hardware considerations, e.g. complicated calibration procedures, external VREF (mentioned) etc. So, if you do app the config, is the integrated one as good?
The integrated ones usually have nice ways to integrate with timers and other onboard periphs.
Weirdly honest deal, haha.
Non-linear as hell - and evil side effects once you use the calibration curves.
There are a bunch of reasons but the primary reason is that good ADCs are made using a different mixed signal process than microcontrollers. MCU ADCs are capacitive charge-balancing successive-approximation type which limits their sensitivity and precision.
Standalone ADCs also eliminate significant sources of noise like temperature fluctuations and electronic noise (the digital logic on the chip often runs at less than 1Mhz for example)
Only ugly two-chip solutions or hyper exotic stuff with no community.
No competition or no market?
I can't imagine Espressif is selling much volume of these chips.
The fact that they can't even fix their SPI module would tend to indicate that their engineering staff is very thin.
https://www.espressif.com/en/news/1_Billion_Chip_Sales
Takes an analog signal from something like light or sound and convert it into a digital signal.
Acronyms introduced in an article should be spelled out at least once please.
https://youtu.be/upTgM_S5rAQ
And if you want to see CERN's multimeter, check this out.
https://youtu.be/D28uSzCs7-k
Marco Reps is a treasure.
That the ADS1115 costs <$1 on LCSC means they buy millions from them every year. They are one of the biggest trustable players in Asia.
I have access to our internal STM32 pricing. You'd be shocked.
One supplier I developed a relationship with showed us their internal numbers and it was $1,000-3,000 per wafer for 130nm-180nm nodes with a minimum order of 25 wafers. Once the part is designed and the mask is made, the cost is mostly just the setup plus whatever they want for the IP. The silicon itself is often cheaper than the packaging around it.
https://www.lcsc.com/product-detail/C2954567.html
They are huge step ahead: the upcoming CH32H417 has pretty much all PHYs integrated (!). For 10/100M Ethernet, USB-C 5GBbps and USB HS 480Mbps. That dramatically reduces the components needed to get that stuff running.
I also build a small robot with the ultra cheap CH32V003. That's a full fledged 48MHz microcontroller with 16kb flash and 2kb SRAM. Fun little thing.
If you are used to the ST HAL you will be able to work with them within 10 minutes. Their API style is similar.