Triple-Level Cell NAND

The phrase 3D TLC combines two independent design choices: stacked cells and three-bit encoding. It is not a fourth NAND encoding category. Samsung's 870 EVO provides a concrete naming example: its specification describes V-NAND with 3bit MLC.

Capacity variants within one TLC family can behave differently. In the cited 870 EVO revision, Samsung lists a common cache-assisted sequential-write ceiling but different rates after the TurboWrite region. The table is a vendor specification example, not a Hesela measurement or a statement about every TLC drive.

Do not interpret a TBW warranty limit as the instant the NAND will fail. The EVO datasheet ties warranty coverage to time or written bytes, whichever comes first. Use the particular capacity and revision, and distinguish the rating from observed reliability.

For a sustained-write comparison, record drive fill, firmware, workload, temperature and the measured interval. Report the throughput over time and identify whether writes stayed in a cache-assisted region. A short burst result cannot by itself describe a long transfer.

TLC and QLC are alternatives with different design trade-offs, not a mandatory replacement sequence. Start with the application's write volume, latency requirements and recovery guarantees, then verify the complete device. No market-share estimate is inferred from these component descriptions.