Sudden power outages are common accidents in industrial scenarios, caused by grid fluctuations, equipment failures, natural disasters, and other factors. When a sudden power outage occurs, cached data in ordinary memory cards has not been completely written to flash memory, easily leading to file system crashes, data loss, and program corruption, further causing industrial equipment malfunctions, production line shutdowns, and data traceability difficulties. The power-fail protection technology of industrial-grade memory cards is designed to address this problem.

The core principle of power-fail protection technology is to build an emergency power supply and data protection mechanism through built-in backup power (supercapacitors or lithium batteries) and intelligent control chips. When a sudden power outage is detected, the control chip quickly triggers the protection mechanism, activating the built-in backup power to supply power to the control unit and flash memory chips, gaining hundreds of milliseconds to several seconds of buffer time. It pauses new data writing requests, prioritizing the complete transmission and solidification of unwritten cached data to flash memory before cutting off the backup power.

Supercapacitors are preferred for power-fail protection modules due to their fast charge-discharge speed, long cycle life, and strong high-temperature resistance. Lithium batteries are only used in some low-power scenarios due to limited life and poor low-temperature performance. The stable operation of power-fail protection requires in-depth collaboration between hardware design and software algorithms, not just adding a backup power supply. In hardware, supercapacitor capacity must match cache size and write speed to ensure sufficient power supply time. Control chips need microsecond-level response speed for power outage detection.

In software, data writing algorithms are optimized to prioritize cached data and suspend non-critical tasks during sudden power outages, collaborating with ECC technology to ensure data integrity. Consumer-grade cards rarely have power-fail protection, with only some high-end models equipped with basic capacitors unable to achieve complete data protection. Different scenarios have varying needs: PLC and CNC machines require power-fail protection to avoid program loss; financial terminals need it to prevent transaction data loss. Confirm core parameters such as backup power duration and response speed when selecting.