Flash Memory Reader
Flash is a semiconductor memory that is widely used in consumer and professional electronic devices. We can find Flash memory in memory cards, USB pen drives, solid state disks and similar applications. Sometimes the data gets corrupted or deleted and in order to fix the problem we need to access the memory with PC where we can try to recover the data.
Each flash memory media has two major parts: interface electronics and flash memory chips. Interface electronics or the controller takes care for all the data that is read or written. Flash memory chips actually store the data. They need power only during reading or writing. But if the controller fails the data becomes inaccessible. However, we can still access it but with special flash memory reader and data recovery software.
Flash Memory Readers
The purpose of flash memory reader is to access the memory with PC. In general there are two types of flash memory readers. The first type of readers only provides USB interface for some memory device that can not be directly accessed by the computer. The second type of flash memory readers connects directly to memory chips and provides access at the lowest level. While the first type of memory readers is commonly used mainly to transfer files to and from the computer, the second type of flash memory readers is used by data recovery experts to access the data from failed memory devices.
USB thumb drives or USB flash disks need no special reader because they already have a built-in USB interface. Normally you simply insert the USB flash drive into USB slot and the thumb drive becomes visible as a disk. If the disk is not mounted or visible in the operating system then this is a sign of failed controller. In such case you need special flash memory reader to bypass the failed electronics and read the data directly from the chips. However, a better approach is to find a data recovery service as they have the tools and knowledge needed for data recovery.
Memory Card Readers
Memory card readers are simple devices that allow us to connect common memory cards to the computer. Compact Flash (CF), Secure Digital (SD), MultiMediaCard (MMC) and other types of memory cards can not be connected directly to the computer. Memory card readers provides necessary interface. There are two types of memory card readers: internal and external. Internal card reader is usually located in the place of floppy drive. Internally it is connected to the motherboard. External card reader usually has USB interface which also powers the reader. Both types of readers behave like external disk drives. The memory card is visible as a disk drive which can be formatted with one of the supported file systems and used as normal disk drive.
Memory card reader is also needed when digital camera can not read or write to the memory card. If the memory card controller is still working it is very likely that only the file system is corrupted. In such cases you can try to recover files or reformat the card. But if you can not access the card then the controller has failed and you need either flash memory reader to access the memory chips or help from data recovery experts.
External Disk Interfaces
Solid state disks (SSD) also use flash memory. They usually have standard hard drive interface like parallel ATA or SATA. This interface allows direct connection of the drive to the motherboard. But to do this you need to power down the computer and open it to access the motherboard. If you only need to transfer some data you can use USB disk interface which acts like a bridge between drive’s native interface and USB. This way you can also recover files, however, for best results it is advisable to connect it directly to the motherboard to have the disk access at the lowest level.
Like with other flash memory media SSD has interface electronics (SATA controller) which can fail. To access the data you need a flash memory reader.
Low Level Flash Memory Reader
Every flash memory device has memory chips which can be accessed directly. To do this you need to remove them from the device. This operation implies using soldering station and some experience with SMD devices. The next step is reading the chips with special flash memory reader which has sockets for typical flash chips. Once the raw data is read it needs to be assembled in a way to recreate the original disk. For this purpose special data recovery software is used—usually it comes with flash memory reader.
Flash memory readers typically have USB interface and software which allows direct access to flash memory chips. In order to use such reader you need to have access to memory chips which is beyond the reach of typical users of memory devices. Therefore, flash memory readers are mainly used by data recovery companies which have necessary tools and knowledge needed for the complete data recovery process. However, if you need such flash reader you can purchase one (e.g. PC-3000 Flash SSD Edition) but it is pretty expensive.