NONVOLATILE SEMICONDUCTOR STORAGE DEVICE AND ITS AUTOMATIC TEST METHOD

摘要

PROBLEM TO BE SOLVED: To provide a nonvolatile semiconductor storage device which can perform the defective bit sensing of a memory cell which can store multi-value data in a chip, and its automatic test method.

SOLUTION: The nonvolatile semiconductor storage device includes: a memory cell array which is constituted by arranging a plurality of memory cells which can store multi-value data and has bit lines which are connected in common to a drain domain of a plurality of memory cells; a sense amplifier circuit which has a plurality of sense amplifiers and in which each sense amplifier outputs a high degree or a low degree of bit line potential to predetermined reference potential as binary data; a multi-valued circuit which generates multi-value data stored in a memory cell based on a plurality of binary data outputted from the sense amplifier circuit; a selection circuit which selects either of binary data outputted from the sense amplifier circuit or a multi-value data outputted from the multi-valued circuit; a verify circuit which performs the comparing evaluation of binary data or multi-value data with an expected value; and an internal control circuit which sets up an expected value held in a verify circuit.

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