To provide a SDRAM refreshing memory capable of performing verification by setting a refreshing period equal to that of actual use.

The SDRAM refreshing circuit includes: a command monitoring part 11 for monitoring a refreshing command issued from a logical emulator 1 to a SDRAM 3; a replenishment refreshing command-issuing part 12 for issuing a replenishment refreshing command when the command monitoring part 11 detects the refreshing command; and a command selection part 13 for selecting the replenishment refreshing command when the replenishment refreshing command-issuing part 12 is allowed to issue the replenishment replenishing command, and for selecting the command from the logical emulator 1 when the replenishment refreshing command issuing part 12 is inhibited from issuing the replenishment refreshing command.

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