Memory device, memory system, and operating method of memory device

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

• receiving a read duty cycle correct command and a read enable signal from a memory controller;
• when the read enable signal is received, performing a read duty cycle correct operation, based on the read duty cycle correct command, and outputting a data strobe signal, based on the read duty cycle correct operation;
• and
• receiving the output data strobe signal, dividing the received data strobe signal, and performing a write duty cycle correct operation,
• wherein the performing of the write duty cycle correct operation comprises dividing the data strobe signal, based on preset criteria, and correcting a duty cycle of the divided data strobe signal, based on a first rising edge and a first falling edge of the received data strobe signal.

A memory system comprising:

• a memory controller configured to generate a read duty cycle correct command and a read enable signal;
• and
• a memory device configured to perform a training operation with respect to a read signal and a write signal,
• wherein the memory device comprises:
• a first pad configured to receive the read enable signal from the memory controller;
• a second pad configured to receive a read duty cycle correct command signal;
• a first duty correction circuit configured to perform a read duty cycle correct operation, based on the read duty cycle correct command signal received from the memory controller, when the read enable signal is received, and output a data strobe signal, based on the read duty cycle correct operation;
• and
• a second duty correction circuit configured to receive the data strobe signal from the first duty correction circuit and generate a divided data strobe signal by dividing the received data strobe signal,
• wherein the second duty correction circuit is further configured to divide the received data strobe signal, based on preset criteria, correct a first duty between a first rising edge and a second falling edge of the divided data strobe signal, and correct a second duty between a first falling edge and the second falling edge of the divided data strobe signal.