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Electronics => Repair => Topic started by: Greybeard on January 05, 2021, 11:12:09 am

Title: FRAM/NVRAM from ebay
Post by: Greybeard on January 05, 2021, 11:12:09 am
I've bought 2 "new" batches of FRAM from same ebay seller.
First batch, delivered in IC shipping tubes, has random data or sort of data pattern.
Second batch, delivered in heat-sealed carrier tape, is complete empty (FF).

What do you think is the probability, that the first batch is used/recycled components?
How can I test the reliability (data retention) of those questionable items?
Title: Re: FRAM/NVRAM from ebay
Post by: CJay on January 05, 2021, 11:23:22 am
Probably used but I've had NOS EEPROM devices from a UK seller  (one I've actually met and trust) which contained data, I have a feeling it was probably stock that had been programmed by the manufacturer (Microchip) for their client and latterly sold as surplus or bankrupt stock.

No idea if you can tell how many times it's been written to, I suppose you could random sample a few and stress test it, or just throw it back at the seller and request either parts in sealed tape or a refund.

 
Title: Re: FRAM/NVRAM from ebay
Post by: amyk on January 05, 2021, 10:18:23 pm
If you want to post the data for us to inspect, maybe we can find something interesting in it...

Even if it's used, all the data I've found on FRAM suggests the number of write cycles is so high as to be essentially infinite, so unless what was previously using it was dedicated to abusing it as much as possible, you're unlikely to even notice.
Title: Re: FRAM/NVRAM from ebay
Post by: wraper on January 05, 2021, 10:38:45 pm
What do you think is the probability, that the first batch is used/recycled components?
Quite high. To investigate, we would need some photos at least, preferably from top, bottom and side.
Title: Re: FRAM/NVRAM from ebay
Post by: TheSteve on January 06, 2021, 08:44:38 pm
I'd say 100% they are used/pulls. All of the ones I've purchased have been(even if advertised as new), but all test fine and have had zero issues.