Memory system, and a method of controlling an operation thereof

A method of controlling an operation of a memory system, the method comprising:

• storing information about weak cells in a first storage unit of a memory device by testing the memory device which includes a plurality of memory cells;
• transmitting an operation command signal to the memory device from a memory controller;
• in response to the operation command signal being received at the memory device and a memory cell corresponding to the operation command signal being one of the weak cells, transmitting information about the weak cell to the memory controller from the memory device;
• storing information about a weak cell having a shortest data retention time or a longest write time in the memory controller, based on the received information about the weak cell;
• and
• controlling a refresh operation, a read operation, or a write operation of the memory device, based on the information stored in the memory controller.

A memory system, comprising:

• a memory device including a memory cell array and a first storage unit including information about weak cells in the memory cell array;
• and
• a memory controller,
• wherein the memory controller is configured to provide a write command and an address of a memory cell to be written to the memory device,
• the memory device is configured to compare the address of the memory cell to be written with the information about the weak, cells in the first storage unit and if the memory cell to be written is a weak cell, the memory device is further configured to provide the information about this weak cell to the memory controller,
• the memory controller is configured to store the information about the weak cell in a second storage unit and provide a refresh command to the memory device to refresh the weak cell on the basis of the information in the second storage unit.