If all attempts to Data Recovery from physical crashed USB flash drive have failed, the last resort is to attempt recovery from the memory chip directly. Generally speaking, the success rate is relatively high, but never certain. Because there are always obstacles. As for the quality of the Data Recovery , it can be perfect, zero or partial depending on the factors below.
memory chip :
The memory chip is an electronic component that can have its own malfunctions. We can talk about two main failures:
- Natural degradation of cell quality. There are techniques to slow down and delay this type of wear, in particular those concerning ” wear leveling”. But after a certain number of write cycles, wear gradually sets in and causes CRC reading errors (Cyclic Redundancy Check). The quality of the recovered data may be affected.
- Permanent failure of the memory chip. In this case, there is no hope of recovering the data.
Reading quality :
Data harvested from the memory chip may suffer degradation due to CRC related to worn cells. In order to overcome these CRC errors, there is the ECC (Error Correction Code) technique. This is the additional data written to the memory chip for each page of the memory chip to ensure user data integrity. But the capacity of the ECC is not expandable. If the amount of the CRC is very large, the reconstruction of user data may become impossible.
Controller Simulation :
If the memory chip is usable and the data quality is correct (less than 50% errors), we can hope for good quality data recovery. The only requirement is simulation of the controller functions to reverse any changes made by the controller. Otherwise, no hope of Twitter data recovery from physical crashed USB flash drive.
Quality of recovered data :
If all operations are done successfully, the question of quality of data recovered from physical crashed USB drive may be questionable. From the above discussions, it can be seen that the quality of the data is proportional to the net amount of read errors after correction by ECC.
- If the errors affect the user’s data, it will be affected. For example, we might see a green line in an image. The smaller the file size, the greater the effect.
- On the contrary, if the data is in areas not used by the user, then the errors will have no effect.