How can eBay Mega 128a be so cheap?

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The "respectable suppliers" price the atmega 128a at about $4 per chip. However, on ebay you can find them at $1 or less. How is this possible?

 

I thought: surely they are fakes, but let me buy a couple and check. I did that several months ago and forgot about it, but today, I found one in a drawer and decided to test it. I haven't run an actual program yet, but it does have the expected signature (0x1e9702), and the flash can be programed and read back - I programmed some data at address 0x1F000, near the top of the flash to see if it was actually there, and it is.

 

The mere fact that the programmer can talk to the MCU means there is some kind of AVR there...

 

So, what gives? Are they semi-defective? Stolen?... What do you guys think?

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I've seen a variety of explanations, ranging from after hours production runs by employees selling them on the side, chips that failed some QA check or another and get sold as kind of a gray market deal, surplus from a production run somewhere (bonus:  sometimes they come programmed with fuses that require HV programming to recover), and probably yes chips that were stolen.  I've only ever seen proof of the surplus chips one, having had received a bunch of attiny13s that were already programmed.

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El Tangas wrote:
The "respectable suppliers" price the atmega 128a at about $4 per chip. However, on ebay you can find them at $1 or less. How is this possible?
Distributor's margin.

Some distributors are not tier one but are still qualified distributors that have reduced overhead and/or operate due to surplus.

Can get a mega128A from a "non-authorized" distributor for about double the Ebay price.

El Tangas wrote:
So, what gives? Are they semi-defective? Stolen?... What do you guys think?
A part that has a subtle defect can still be a fit for one's application; what to do with such parts is a manufacturer's decision which can contribute to the grey market.

If a part's price is really too good to be true then that may be an indicator of a black market part (stolen, etc); manufacturers can limit this by being organic (in-house die fabrication and/or packaging and final test) and by supply chain auditing.

"semi-defective" can be due to the part being salvage.

 


https://www.ibselectronics.com/about-us/

http://www.ewinginc.com/

both via

https://octopart.com/atmega128a-au-microchip-42866769

 

Edit : both, surplus

 

"Dare to be naïve." - Buckminster Fuller

Last Edited: Thu. May 25, 2017 - 07:42 PM
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Thanks for the insight guys. Yeah, it seems those suppliers also have discount 128As, interesting. Mine is not pre-programmed or anything, it seems to have factory settings (unprogrammed flash and EEPROM and default fuse settings).

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The Mega128 is an "obsolete" part.  It was the high-end CPU of the AVR family when it was released about 20 years ago, and very expensive then.  Yes it is still made and sold, and a few designs are still written for it.  But it is too "big" for the vast number of applications used by AVR.  Any application that uses 128K of flash generally goes to an ARM variant today.  Fewer and fewer are sold each year.  An exception might be the Mega2560, because it is used on Arduino Mega.  But even then, so few Arduino Megas are sold to be constantly putting manufacturing design resources into this individual chip variant.

 

Mouser and DigiKey will keep them in stock at a relatively high price.  But the other suppliers will want to get rid of their current stock at a low price.

 

Stolen parts, semi-defective units, counterfeits, etc....   I would discount these stories.  Who would steal a 20-year-old microprocessor that sells for a dollar?   Who would go through the trouble of counterfeiting it?   I would discount the reports of semi-defective units.  Modern IC fabs don't produce semi-defective units as they might back in the 1970s.

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Simonetta - your beliefs don't match up to my reality.
Firstly there was the mega103 which was replaced by the mega128 then the mega128a. Some of my designs from the early 2000's are still in volume production using a mega128a. Changing the design to a more modern device would involve a bit of money - you need to chsnge the pcb, code ,re-certify etc. That can easily run into a few tens of thousands of dollars. Even more if automotive, military, medical and so on. So as long as the parts are available, then they will be used.
As for harvesting parts from old boards - you've not been to Shenzhen then. Schoolkids, gramps, mamma, you name it will sit down doing menial tasks. Give gramps a laser etcher and he will happily convert 75176s into max485s. Your western view on economics doesn't work there. There's a job for everyone.