SP Industrial Implements Dual Secure Design for Power Failure Protection (PFP)
SP Industrial’s complete series of SSDs are equipped with power shielding firmware architecture protection to sense unstable voltage and power down to stop receiving host commands.
SP Industrial’s R series of SSDs implements Advanced PFP with industrial grade polymer capacitors to gain more time for the data flushing process from DRAM cache to FLASH during sudden power-off situations.
How Does the SSD Controller Manage Power Failure?
SSD FW stored inside NAND Flash is called a system block. When the system power is on, the SSD will load the related mapping table and initial commands into DRAM for the SSD controller (Figure 1-A). When VCC is under 4V (Figure 1-B), the SSD Controller will enable the Power Shielding function. During this period, the SSD controller will start to flush DRAM cache data save into FLASH to secure the user data in a limited time. At the same time, when VCC is under 4V, the SSD controller will stop receiving commands from the Host (Figure 1-C) to protect itself. During this period, the Host cannot recognize the SSD and the SSD will stop working until VCC resumes and becomes stable again.When VCCF is under 2.7V (Figure 1-D), the SSD controller will initiate the FLUSH command to write back the mapping table back to the flash system block. During this period, the Host cannot recognize the SSD and the SSD cannot work, even if the power resumes. In order for the SSD to start working normally again, you need to turn the power ON/OFF for the Host to restart the SSD. During SSD operation, data is temporarily stored in the DRAM cache to reduce the performance gap between the Host interface and the NAND Flash memory. However, in cases of unexpected sudden power loss, such as unplugging the power from the system, sudden battery loss, or unplugging devices from the system, the flushing process cannot be completed and may cause serious device failure. Silicon Power’s Dual Secure Design for Power Failure Protection (PFP) prevents such issues with a firmware-based protection mechanism and a capacitor backup circuit.
How Does the Advanced PFP Mechanism Work?
The Power Shielding function integrates built-in VDT and firmware mechanism. The trigger alert is able to monitor an abnormal power drop and take instant action, such as prohibit receiving data from the Host and backup mapping/linking table into FLASH, as soon as potential power failure is detected.Advanced PFP is a way to gain more time for the data flushing process from DRAM cache to FLASH under sudden power-off situations by using dedicated polymer capacitor components. These capacitors are charged during power on and offer charged power to the SSD circuit under sudden power-off situations.SP Industrial’s Advanced PFP technology SSD provides at least 20ms to ensure the data flushing task can be completed within the discharge time. Furthermore, it always passes the Power Cycling test under abnormal conditions at least 3,000 times.
How Does the SSD Controller Manage Power Failure? (2.5”SSD R Series)