Apparatus and method for performing target refresh operation

An operating method of a memory apparatus, comprising:

• a sampling operation of sampling an input address through a sampling method corresponding to a value of a first selection signal among at least two sampling methods designed using different algorithms;
• a storage operation of storing up to N number of addresses having different values in N number of address latches, respectively, among addresses sampled in the sampling operation;
• an arranging operation of:
• determining an output sequence of the stored addresses through an arranging method corresponding to a value of a second selection signal among at least two arranging methods designed using different algorithms, and
• setting, as a target address, an address stored in a latch corresponding to the output sequence among the N number of address latches;
• a determination operation of determining the value of each of the first selection signal and the second selection signal based on a number of latches in which addresses are stored among the N number of address latches;
• and
• an operation of performing a target refresh operation on a row of memory cells corresponding to the target address,
• wherein N is a natural number equal to or greater than 2 .

An operating method of a memory device including rows of memory cells, the operating method comprising:

• sampling input addresses according to a selected one of sampling schemes;
• latching the sampled addresses such that the latched addresses are different from one another;
• arranging the latched addresses according to an arranging scheme;
• selecting target addresses sequentially from the arranged addresses;
• and
• performing target refresh operations on the rows corresponding to the target addresses, respectively,
• wherein the sampling includes selecting the sampling scheme based on a number of the latched addresses.