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    Array organization

    Sensing and Sense Amplifiers

    5 sourced facts on Sensing and Sense Amplifiers, each tied to the source it comes from.

    5 facts filed under Array organization: all 5 are reported by a second source. Each was checked against the source’s own words, so its figures appear there, and each names where it comes from. The idea is taught in Part 3, From Cell to Die.

    Secondary sources

    • A NAND string passes only about 100 to 200nA.

      Published resultFigures: 100-200 nA string currentInside NAND Flash Memories

    • The read threshold current sits at tens of nA; with state-of-the-art sub-30nm technology a value above 50nA is not available, so sensing takes microseconds (100mV x 2pF / 50nA is 4us best case).

      Published resultFigures: tens of nA threshold; 50 nA maxInside NAND Flash Memories

    • Shielded-bitline designs typically read a wordline in two passes, even bitlines then odd.

      Published resultSemiconductor Memories and Systems

    • In a published precharge example a 2pF bitline is charged by 1V in a precharge time of 10µs.

      Published resultFigures: 1V; 10µs; 2pFInside NAND Flash Memories

    • In a published NAND sensing analysis, 4µs is a best-case bitline evaluation time; in reality the evaluation time is in the range of 10µs.

      Published resultFigures: 2pF; 100mV; 10µs; 50nA; 4µsInside NAND Flash Memories

    Sources

    Primary is the original paper, standard or datasheet. Secondary is a review, a vendor summary or a news report. Measured is my own test data.

    Show all 2 sources
    • SecondaryInside NAND Flash MemoriesSpringer, 2010
    • SecondarySemiconductor Memories and SystemsWoodhead Publishing (Elsevier), 2022