| 摘要 |
PROBLEM TO BE SOLVED: To provide a control unit capable of canceling a self-refresh state of a storage device at a suitable timing without losing data on the storage device with a simple circuitry. SOLUTION: An AND circuit 20 is provided between a main control unit (MCU) 10 and an SDRAM 12 for automatically performing a refresh operation by itself when a refresh operation is required for storage and besides, a storage device is in a self-refresh state. When the MCU 10 shifts from a power saving mode to a non-power saving mode, the self-refresh state of the SDRAM 12 is maintained while an MCU_Reset signal at Low level is output, regardless of an output level of an MCU_CKE signal, by outputting an AND signal (CKE signal) obtained by performing AND operation of the MCU_Reset signal at Low level for initializing the MCU 10 output from a RESET_IC 18 with the MCU_CKE signal. COPYRIGHT: (C)2007,JPO&INPIT
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