Memory system and operating method thereof

A memory system comprising:

• a memory device comprising a memory cell array and a control circuit;
• a memory controller configured to determine a read mode among a plurality of read modes associated with different read speeds based on a reliability index of the memory device;
• and
• a temperature sensor configured to measure a temperature of the memory device to generate a temperature value,
• wherein the control circuit is configured to:
• set a compensation sensing parameter based on the temperature value,
• determine a sensing parameter by applying the compensation sensing parameter to a basic sensing parameter corresponding to the read mode, and
• read data from the memory cell array based on the sensing parameter.

An operating method of a memory system, the operating method comprising:

• receiving, by a memory controller, a read command for a memory device, wherein the memory device comprises a memory cell array;
• determining, by the memory controller, a reliability of the memory device;
• determining, by the memory controller, a read mode of the memory device among a plurality of read modes having different read speeds based on the reliability;
• setting, by the memory device, a compensation sensing parameter based on a temperature and the read mode of the memory device;
• and
• reading, by the memory device, data corresponding to the read command based on a basic sensing parameter corresponding to the read mode and the compensation sensing parameter.