Device Family: Stratix® V E, Stratix® V GS, Stratix® V GT, Stratix® V GX

Type: Answers

Area: EMIF, Intellectual Property


IP Product: DDR3 SDRAM Controller MegaCore supporting UniPHY

Why do I not see DQS tracking signals when I implement UniPHY based DDR3 SDRAM Controller above 533MHz?

Description

In Quartus® II software version 11.1SP2 and earlier, the DDR3 SDRAM UniPHY based controller IP turned on the DQS tracking feature at speeds above 533MHz so the signals afi_ctl_refresh_done, afi_seq_busy, and afi_ctl_long_idle for the DQS tracking were present in the IP.

In Quartus II software version 12.0, upon further analysis it has been determined that DQS tracking is not needed in Stratix® V devices at any supported frequencies so the feature has been disabled.

Workaround/Fix

Regenerate the DDR3 SDRAM UniPHY based controller in Quartus II software 12.0 to get the most updated version of the IP.