In scenarios like industrial automation, rail transit, and financial terminals, the service life of memory cards is directly related to equipment operation and maintenance costs and system stability. A failure caused by exhausted memory card life can lead to significant losses such as production line shutdowns and data loss. P/E cycle and TBW are the two core indicators for measuring the service life of industrial-grade memory cards, yet most users have misunderstandings about their definitions, correlations, and practical applications, which can lead to incorrect selection and affect long-term equipment operation.

P/E cycle refers to the process in which a flash memory chip completes one full "erase old data - write new data" cycle, serving as the basic measure of the physical life of flash memory. Since flash memory chips have a physical limit on erase-write times, a higher P/E cycle count means a longer theoretical service life. Different flash memory types have significant differences in P/E cycles: industrial-grade cards using SLC (Single-Level Cell) flash memory can achieve over 100,000 P/E cycles, and some military-grade models even exceed 1 million times. MLC (Multi-Level Cell) flash memory offers 10,000 to 30,000 cycles, while TLC (Triple-Level Cell) flash memory used in consumer-grade cards only has 3,000 to 10,000 cycles, with actual life possibly shortened by writing frequency.

TBW is a more intuitive indicator than P/E cycle, representing the total amount of data that a memory card can safely write throughout its lifespan, usually measured in TB. TBW is directly related to P/E cycles, and the simplified calculation formula is: TBW = Flash Capacity × P/E Cycle Count × Flash Type Coefficient (1 for SLC, 0.5 for MLC, and approximately 0.33 for TLC). Industrial-grade cards generally have a TBW of ≥50TB, and high-end SLC models can reach hundreds of TB, while consumer-grade cards typically have a TBW below 10TB.

For example, a 16GB SLC industrial-grade memory card with 100,000 P/E cycles has a corresponding TBW of about 1,600TB. If the device writes 50GB of data per day, the theoretical service life can reach 87 years. Even a 16GB industrial card using MLC flash memory has a TBW of 480TB, which can last 26 years with 50GB of daily writing, fully meeting the long-term needs of industrial scenarios. Actual service life is also affected by usage scenarios, writing modes, and ambient temperature. The wear-leveling technology of industrial-grade cards can extend actual life by 20% to 50% by intelligently distributing data. When selecting, calculate the theoretical life based on daily writing volume and reserve more than 30% redundancy.