Semiconductor storage device

Abstract

A word-line controller applies a voltage to a selected word-line. A bit-line controller applies voltages to bit-lines. A detector detects data of memory-cells. A write sequence of writing data in selected memory-cells connected to the selected word-line has at least one write-loop including a write operation of applying a plurality of write voltages with the word-line controller and the bit-line controller, and a verify operation of verifying with the detection circuit whether a threshold voltage of each of the selected memory-cells has reached a plurality of reference voltages for corresponding write data. The word-line controller and the bit-line controller select a write voltage corresponding to a threshold voltage of each of the selected memory-cells from among the write voltages with respect to each of the write-loops, and apply the selected write voltage to the selected memory-cell in a subsequent write operation.