One of the risks for a drive based on NAND FLASH memories is the occurrence of a sudden power failure. The most significant negative effects of this phenomenon include the interruption of data (including the FTL mapping table) from the DRAM buffer to the FLASH memory, which entails the risk of data loss.

A solution that effectively protects data from the occurrence of the above problems is a hardware protection measure called Power Loss Protection (PLP).

The basic idea behind PLP is to modify the controller’s firmware and design suitable circuits equipped with tantalum capacitors on the drive’s PCB. Their role is to collect an electrical charge, which, when released, allows the controller to finish writing data in the event of a sudden power failure. In this way, the device is able to efficiently perform the transfer of critical data (FTL table and user data) to non-volatile FLASH memory.

The principle of the Power Loss Protection functionality is therefore as follows:

  1. the power monitor notes a voltage drop – all internal controller processes are suspended.
  2. data transfer from the buffer to FLASH memory is initiated. At this point, the power supply to the drive is maintained by releasing the electrical charge stored in the tantalum capacitors.
  3. When power returns, previously stored data is redistributed to the allocated NAND blocks.

For example, the Goodram Industrial M.2 SATA solution equipped with a PLP solution is capable of sustaining power up to a maximum of 30 ms. This time is sufficient to perform the aforementioned operations, guaranteeing data security.

As can be seen, in the case of PLP functionality, the process of protecting critical information is not complex in terms of the software itself, but requires an appropriate re-arrangement of the media architecture. In addition to the aforementioned M.2 drive, we can also offer other formats that take into account the described functionality, adjusting their bill of materials to the individual requirements of the customer.