CONTROL DEVICE AND CONTROL METHOD FOR SEMICONDUCTOR MEMORY
PROBLEM TO BE SOLVED: To provide a control device and control method for a semiconductor memory, which can suppress the degradation of the reliability of read data.SOLUTION: A provided method includes the steps of: setting all memory cells of a memory cell group comprising a plurality of memory cell...
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Main Authors | , , |
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Format | Patent |
Language | English Japanese |
Published |
15.12.2014
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Subjects | |
Online Access | Get full text |
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Summary: | PROBLEM TO BE SOLVED: To provide a control device and control method for a semiconductor memory, which can suppress the degradation of the reliability of read data.SOLUTION: A provided method includes the steps of: setting all memory cells of a memory cell group comprising a plurality of memory cells, to the state of a first logic level; performing data write for shifting a desired memory cell in the memory cell group to the state of a second logic level; when obtaining a read data piece by performing data read from the memory cell group in response to a read instruction, detecting error bits by performing error detection processing to the read data piece; and determining that the read data piece is invalid data if the number of error bits having the above-described first logic level in the error bits detected from the read data piece is more than the number of error bits having the second logic level.
【目的】読出データの信頼性低下を抑えることが可能な半導体メモリの制御装置及び制御方法を提供することを目的とする。【構成】複数のメモリセルからなるメモリセル群内の全メモリセルを第1の論理レベルの状態に設定してから、当該メモリセル群内の所望のメモリセルを第2の論理レベルの状態に遷移させるデータ書込を行い、読出指令に応じて当該メモリセル群からデータの読み出しを行って読出データ片を得るにあたり、当該読出データ片に誤り検出処理を施すことにより誤りビットを検出し、この読出データ片から検出された誤りビットの内で上記した第1の論理レベルを有する誤りビットの数が第2の論理レベルを有する誤りビットの数よりも大なる場合に、この読出データ片が無効データであると判定する。【選択図】図1 |
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Bibliography: | Application Number: JP20130115559 |