Memory system

A memory system comprising:

• a semiconductor memory including:
• a plurality of memory cells, each of the memory cells being configured to store first data based on a first threshold voltage;
• word lines connected to the memory cells;
• and
• a sequencer configured to execute a program loop that includes a program operation and a verify operation in a write operation;
• and
• a memory controller which controls the semiconductor memory,
• wherein:
• the memory controller transmits a write command and write data to the semiconductor memory, and the sequencer performs a first write operation for the write data based on the write command;
• the sequencer executes the program loop repeatedly in the first write operation and terminates the first write operation, when the program loop has executed a first number of times and the verify operation for the first data has not passed;
• and
• the memory controller transmits a first command to the semiconductor memory after the first write operation is terminated, and the sequencer performs a second write operation for the write data based on the first command.

A memory system comprising:

• a semiconductor memory including:
• a plurality of memory cells, each of the memory cells being configured to store first data based on a first threshold voltage;
• word lines connected to the memory cells;
• a sequencer configured to execute a program loop that includes a program operation and a verify operation in a write operation;
• and
• a timer configured to measure execution time of the write operation;
• and
• a memory controller configured to control the semiconductor memory,
• wherein:
• the memory controller transmits a write command and write data to the semiconductor memory, and the sequencer performs a first write operation for the write data based on the write command;
• the sequencer executes the program loop repeatedly in the first write operation and terminates the first write operation, when the timer measures a predetermined time and the verify operation for the first data has not passed;
• and
• the memory controller transmits a first command to the semiconductor memory after the first write operation is terminated, and the sequencer performs a second write operation for the write data based on the first command.

A memory system comprising:

• a semiconductor memory including:
• a plurality of memory cells, each of the memory cells being configured to store data of a plurality of bits based on a plurality of threshold voltages including a first threshold voltage and a second threshold voltage that is higher than the first threshold voltage;
• word lines connected to the memory cells;
• and
• a sequencer configured to execute a program loop that includes a program operation and a verify operation in a write operation;
• and
• a memory controller configured to control the semiconductor memory,
• wherein:
• the memory controller transmits a write command and write data to the semiconductor memory, and the sequencer performs a first write operation for the write data on a word line selected based on the write command;
• the sequencer executes the program loop repeatedly in the first write operation and terminates the first write operation, when verify operation for the first threshold voltage has passed and the verify operation for the second threshold voltage has not passes;
• and
• the memory controller transmits a first command to the semiconductor memory after the first write operation is terminated, and the sequencer performs a second write operation for the write data based on the first command.