Device Family: Arria® V GT, Arria® V GX, Arria® V GZ, Arria® V ST, Arria® V SX, Cyclone® V E, Cyclone® V GT, Cyclone® V GX, Cyclone® V SE, Cyclone® V ST, Cyclone® V SX, Stratix® III, Stratix® IV E, Stratix® IV GT, Stratix® IV GX, 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

What are the AC voltage levels that Quartus® II uses for UniPHY DDR3 and DDR3L tDS and tIS set up derating ?

Description

The AC voltage levels depend on the value set in the Memory Parameters tab -> Memory Device Speed Grade.

This speed grade and the AC voltage level shown below should be used to select the Memory Timing tab  values for parameters tIS (base) and tDS (base)  from the external memory vendor device datasheet 

DDR3
AC175 for speed grades 400.0 (DDR3-800)  & 533.333 (DDR3-1066).
AC150 for speed grades 666.667 (DDR3-1333) & 800.0 (DDR3-1600).
AC135 for speed grade  933.333 (DDR3-1866).

DDR3L
AC160 for speed grades 400.0 (DDR3L-800)  & 533.333 (DDR3L-1066).
AC135 for speed grades 666.667 (DDR3L-1333) & 800.0 (DDR3L-1600).

If the DDR3L device is powered at 1.5V, then the DDR3 AC voltage levels should be used to determine which tIS and tDS base setting values are selected from the external memory vendor device datasheet.

Workaround/Fix

This information is scheduled to be added to a future version of the External Memory Interface Handbook.