This problem affects LPDDR2 products.
In LPDDR2 interfaces targeting Cyclone V devices, if the auto power down mode is enabled, the HPC II memory controller cannot immediately issue a deep power down request in response to a user request to invoke deep power down mode. This situation occurs because the system is unable to exit the auto power down loop when a deep power down request occurs.
When a deep power down request occurs, soft logic within the IP automatically triggers a self refresh, allowing the system to exit the auto power down mode and process the deep power down request after completion of the self refresh.
This issue does not require a workaround. The purpose of this erratum is to explain the reason for the automatically generated self refresh, which is visible on the memory bus.
This issue will not be fixed.