To ensure that a memory device operates in self-refresh mode, the memory controller includes (1) a normal-mode output buffer for driving a clock enable signal CKE onto the memory device's CKE input and (2) a power island for driving a clock enable signal CKE_prime onto that same input. To power down...http://www.google.fr/patents/US8139433?utm_source=gb-gplus-shareBrevet US8139433 - Memory device control for self-refresh mode
