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YC's avatar

Unless the ADC was designed to accommodate power or die size, semi company don’t leave performance on the table. if they sell dedicated ADC, they are good ADC. Modern semiconductor process are extremely good. Even cheap ADCs are extremely high performance compared to a few decades ago.

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Rodger Reinhart's avatar

Encountered out the back door Analog Devices parts. years ago. Date codes that Analog had no record of. Wound up buying full reels of parts through Analog Devices shipped direct.

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Dave's avatar

I also got some cheap ADS1115 from Ali, and it happens that one of them was not able to reach the expected full voltage scale. one bit (the second MSB) was failing (glitching). It took me quite some time of software debugging before I realized that the hardware was faulty. The chip was probably a scrap from the manufacturing (This defect must be identified during wafer test). For hobby project let say we can deal with this but for professional stuff...

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Kabaragoya's avatar

I've been using the ADS1015 in one of my designs for the past year, and it's performed well even though I can't make use of the PGA.

My experience has been that pricing on LCSC often feels like taking a taxi in countries that openly charge different rates for locals and tourists. I've also noticed (or become increasingly aware? I'm honestly not sure) that Digikey has gotten significantly more expensive than Mouser and other options over the past year. Tariffs at work!

The reality is that while it's possible these ICs were part of a lot that didn't pass QA and were subsequently smuggled out for selling to us rubes, most claims of counterfeit chips just don't make any sense. The amount of effort required to design and fabricate a copycat chip just to sell it at a discount doesn't make any sense, and that's a polite understatement.

If you can bring up an ADS1115 over I2C and get a reading, it's an ADS1115.

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James Bowman's avatar

Interesting take. We see two prices (ala tourist/local taxis) and scratch our heads thinking "there must be some difference between these taxis rides."

It's a well-understood phenomenon:

https://mru.org/courses/principles-economics-microeconomics/price-discrimination-examples-airlines-arbitrage

Thanks, will mention this as an explanation in the followup.

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Ian McKellar's avatar

I'll be interested to see how different the adafruit version is.

I wonder if it's worth reaching out to TI to ask about the Amazon product.

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YC's avatar

$3 ADC is not a cheap ADC. Cheap ADC is what embedded inside the cheap MCU.

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