I had to replace a flash chip yesterday because it would not read OK at times - and had a byte fail after programming about all the 2M of it. Since I don't do large volumes this is my first ever experience of the kind and I want to ask the group for some insight.
The part was an Atmel at49bv163d ; it was on a netmca board which came for repair (torn power cable...) after a few years at the customer. After replacing it (with an equivalent) things went back to normal.
The device had been opened and tampered with. I think even the flash may have been unsoldered and resoldered but it has been done reasonably clean so I can't say that for sure. [Reverse engineering the netMCA could be considered only by someone uncapable of understanding how hopeless the task is, so needing to unsolder the flash rather than JTAG reading it via the CPU as we do it here and pose no obstacles to might have been opted for....].
So my question is how likely is it for a flash chip like that to wear off after 2-3 times initial programming? Yesterday I did rewrite it may be 10 times but it showed the symptoms from the very start.
My curiosity is directed towards the flash durability and perhaps towards what has been done to the device.
Dimiter
------------------------------------------------------ Dimiter Popoff, TGI
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