Causes of physical failure in SD cards:

1. Increase in bad blocks: As usage time increases, more and more bad blocks may appear in the flash memory units of the SD card. When the number of bad blocks reaches a certain level, it may render the entire SD card unusable.

2. Issues with expanded capacity cards: The use of expanded capacity SD cards (cards that display a larger capacity than their actual storage) can easily lead to failures when data exceeding the actual capacity is written, resulting in the card not being recognized.

3. Solder joint detachment: Collisions or drops can cause solder joints to detach or result in poor soldering, leading to hardware failure.

4. Electrostatic damage: Electrostatic discharge can cause instant damage to the electronic components of the SD card, especially when inserting or removing the card without proper anti-static measures.

        For data recovery from an unrecognized SD card, you can choose Tianwei Data Recovery Center, located in Rooms 607 and 609 of the Bainaohui Technology Building. The memory card brands that can be recovered include:

1) Maxell Tianjin Memory Card Data Recovery.

2) HP Memory Card Data Recovery.

3) Aigo Memory Card Data Recovery.

4) Sony Memory Card Data Recovery.

5) Lexar Memory Card Data Recovery.

6) Panasonic Memory Card Data Recovery.

7) Hikvision Memory Card Data Recovery.

8) Bolinke Memory Card Data Recovery.

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