摘要:
A non-volatile memory system utilizes partial block erasing during program operations to mitigate the effects of programming pass voltage disturbances. A programming request is received that is associated with a group of word lines from a block, such as all or a portion of the word lines. The system erases and soft programs the block prior to beginning programming. The system programs a subset of the word lines of the block for the programming request. After programming the subset of word lines, the system pauses the programming operation and performs an erase operation for the unprogrammed word lines of the block. The already programmed word lines and one or more optional buffer word lines may be inhibited from erasing during the erase operation. After erasing the unprogrammed word lines, the system completes the programming request by programming the remaining user data in the unprogrammed region of the block.
摘要:
A programming techniques adaptively sets a pass voltage and an initial program voltage based on a programming speed of a set of memory cells. In one pass of a multi-pass programming operation, a programming speed-indicating program voltage is obtained. For example, this can be a final program voltage or a program voltage at another programming milestone. A pass voltage is determined for another programming pass of the multi-pass programming operation, by providing an adjustment to a reference pass voltage. An initial program voltage is determined for the another programming pass based on an offset from the programming speed-indicating program voltage. The initial program voltage is further adjusted to counteract an effect of the adjustment to a reference pass voltage. The adjustment to the initial program voltage is opposite in polarity and smaller in magnitude than the adjustment to the reference pass voltage.
摘要:
Memory cells which have read noise are identified during a programming pass and an amount of programming is increased for noisy memory cells compared to non-noisy cells. The read noise is indicated by a decrease in the threshold voltage of a cell when the cell is repeatedly read. In one approach, during the programming pass, a cell enters a temporary lockout state when it passes a first verify test and is subject to one or more additional verify tests. Data is stored to identify the cell as a noisy cell or a non-noisy cell based on the one or more additional verify tests. Or, the cells are subject to the one or more additional verify tests at the end of the programming pass. In a subsequent programming pass, the noisy cell is programmed using a stricter verify condition. Or, the noisy cell is kept in an erased state.