{
  "slug": "nand-logical-unit",
  "term": "NAND logical unit",
  "aliases": [
    "NAND LUN",
    "ONFI LUN"
  ],
  "definition": "An ONFI NAND logical unit is the smallest command-execution and status-reporting unit that can operate independently of other logical units.",
  "note": "A target contains one or more LUNs; each LUN has an array and page-register resources. This NAND meaning is separate from a host-facing SCSI logical unit. [onfi4]\n\nIndependent array activity does not create independent data links. LUNs within a target share the host data bus, and only one may drive data output at a time. Command ordering and register handling also impose restrictions. [onfi42]",
  "related": [
    "nand-target",
    "nand-plane",
    "channel-nand",
    "nand-page",
    "logical-unit-number"
  ],
  "citations": [
    {
      "id": "onfi4",
      "title": "ONFI 4.0, sections 1.4.1 and 3: NAND target, logical unit and memory organization",
      "url": "https://onfi.org/files/onfi_4_0-gold.pdf",
      "accessed": "2026-10-20"
    },
    {
      "id": "onfi42",
      "title": "ONFI 4.2, sections 3.1.2-3.1.3: shared data bus and multiple-LUN operation restrictions",
      "url": "https://onfi.org/files/onfi_4_2-gold.pdf",
      "accessed": "2026-10-20"
    }
  ],
  "status": "shipping",
  "advantages": [],
  "limitations": [],
  "supersedes": [],
  "supersededBy": [],
  "firstSeen": null,
  "lastSeen": null,
  "provenance": [
    "ONFI terminology is scoped to the cited editions; component geometry and supported command sequences must be checked for the selected device."
  ],
  "updated": "2026-10-20"
}