Recoverfab - Leading Card Recovery Service 

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2014 Nov 22
04:02 PM EST
 

Have you found that your card is no longer detected, or have you gotten a message that the card suddenly needs to be formatted, even though seconds ago the card was working properly?
Does the computer treat the card as if it hasn't been inserted, or the memory card shows up in File Explorer folder tree but is reported as having no free space? Or perhaps the data on the memory card appears to be corrupted and causes the computer to hang and to be unresponsive when programs try to access, write or read from the card. Another peculiar symptom might be that there are no data or files contained within the card's directories.

Recoverfab is specialized in the recovery of files from all types of flash memory cards/USB flash drives, whether the data is lost due to logical or physical damages.
Flash memory is a technology that is primarily used in memory cards, USB flash drives and SSD (Solid State Drive). Common memory cards are: Secure Digital SD (including mini SD, micro SD, SDHC, SDHC Plus), Compact Flash CF, Multimedia Card MMC, Memory Stick (MS, MS Pro, MS Pro DUO), Picture Card xD.
In cases where no data is recoverable, there will be no charge for the evaluation or data recovery attempt. Data download via FTP or CD/DVD shipment world-wide - at no additional charge!


What is wear-leveling?
Every flash memory is subject to write endurance limitations. After repeated erase and program cycles, the memory no longer retains data. As memory manufacturers have moved to smaller silicon geometries and multi-level cells, endurance levels have dropped. For instance, while memory manufacturers specified their SLC devices at 100 000 cycles, newer MLC devices are now specified at only 10 000 cycles.
Flash memory controllers compensate for this limitation by incorporating complex wear-leveling functions in their firmware. These algorithms track memory usage by block, or page, by matching an age counter that is incremented with each write cycle to a map of the logical and physical sectors on the flash media. Wear-leveling algorithms extend memory IC endurance by automatically instructing the controller to rotate memory writes to blocks with less usage. This function allows the controller to maximize memory IC endurance by ensuring all sectors in a flash IC reach their write limit at the same time.

What is bad block management?
NAND devices are designed to operate with bad blocks in order to achieve high yield in production. Memory IC manufacturers typically specify which blocks are bad in their devices. At initialization firmware-based bad block management functions identify the location of these bad blocks and automatically map them out of the memory array. The firmware then instructs the controller not to use those specified blocks for storage. If any additional bad blocks are discovered as the memory is used, the firmware updates the bad block maps.


Interesting images of NAND-flash memory cards
Typical printed circuit board assembly of SD memory cards
      
Here, controller and memory chips are enclosed in thermoset (prone to breaking).



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