Memory devices, memory systems, and control methods thereof to identify a programming failure

A memory system, comprising:

• a memory controller configured to send a first operation command;
• and
• a memory device coupled to the memory controller, wherein the memory device includes a memory block including a plurality of memory cells, and a plurality of word lines are coupled to the memory block, and
• the memory device is configured to:
• perform a first programming operation in response to the first operation command to program first memory cells coupled to a first word line in the memory block;
• perform a first verification operation to obtain a first number of second memory cells in the memory block that are coupled to the first word line, the second memory cells being those coupled to the first word line and having an erased state as a target state and a threshold voltage larger than a first verification voltage, wherein the first verification voltage is a verification voltage of a first programmed state;
• and
• generate a first state identifier indicating a programming failure in response to the first number being larger than a first threshold, wherein the first operation command is sent to the memory device in response to a number of reads of third memory cells in the memory block being larger than or equal to a preset number.

A method of controlling a memory device, comprising:

• performing a first programming operation in response to a first operation command to program first memory cells coupled to a first word line in a memory block;
• performing a first verification operation to obtain a first number of second memory cells in the memory block that are coupled to the first word line, the second memory cells being those coupled to the first word line and having an erased state as a target state and a threshold voltage larger than a first verification voltage, wherein the first verification voltage is a verification voltage of a first programmed state;
• and
• generating a first state identifier configured to indicate a programming failure in response to the first number being larger than a first threshold, wherein the first operation command is sent to the memory device in response to a number of reads of third memory cells in the memory block being larger than or equal to a preset number.