THRESHOLD VOLTAGE CALIBRATION USING REFERENCE PATTERN DETECTION

摘要

A memory controller identifies a predominant type of error of a memory unit of solid state memory cells. An error type differential is calculated. The error type differential is a difference between a number of charge loss errors and a number of charge gain errors of the memory unit. A VT offset error differential is calculated. The VT offset error differential is a difference between a number of errors of the predominant type at a first VT offset and a number of errors of the predominant type at a second VT offset. A VT offset is determined using a ratio of the error type differential and the VT offset error differential.

主权项

1. A method, comprising:
identifying a predominant type of error of a memory unit of solid state memory cells; calculating an error type differential, the error type differential comprising a difference between a number of charge loss errors and a number of charge gain errors of the memory unit; calculating a VT offset error differential, the VT offset error differential comprising a difference between a number of errors of the predominant type at a first VT offset and a number of errors of the predominant type at a second VT offset; and determining a VT offset using a ratio of the error type differential and the VT offset error differential.