Memory, memory system including the same and method for operating memory

A memory system comprising:

• a memory controller suitable for generating a refresh command with a set interval, and additionally generating write and precharge commands and test data with the refresh command in a test mode;
• and
• a memory including a plurality of word lines to which one or more memory cells are connected and suitable for activating and precharging an adjacent word line that is adjacent to a high-activated word line during a target refresh operation while sequentially activating and precharging the plurality of word lines in response to the refresh command, wherein the memory is suitable for writing the test data to one or more first memory cells connected to the adjacent word line during the target refresh operation in the test mode,
• wherein the high-activated word line is a word line activated over a reference number or a reference frequency, among the plurality of word lines.

A memory system comprising,

• a memory controller suitable for generating an active command and a precharge command sequentially during a target refresh operation, and generating the active command, the precharge command and a write and precharge command sequentially in the test mode;
• and
• a memory including a plurality of word lines to which one or more memory cells are connected and suitable for activating and precharging an adjacent word line that is adjacent to a high-activated word line in response to the active command and the precharge command during the target refresh operation, wherein the memory is suitable for writing a test data to a first memory cell connected to the adjacent word line in response to the active command and the write and precharge command during the target refresh operation in a test mode,
• wherein the high-activated word line is a word line activated over a reference number or a reference frequency, among the plurality of word lines.

A method for operating a memory including a plurality of word lines to which one or more memory cells are connected, the method comprising:

• setting a mode of the memory to a test mode;
• detecting a high-activated word line, which is activated over a reference number or reference frequency, among the plurality of word lines to perform a target refresh operation;
• writing a test data to an adjacent word line that is adjacent to the high-activated word line during a target refresh operation;
• and
• reading data written to the memory cells that are connected to the plurality of word lines.