AR# 42832

MIG 7 Series v1.2-v1.4 DDR3 - FULL calibration mode violates tREFI requirement


MIG 7 Series v1.2-v1.4 DDR3 designs exceed the maximum refresh time in FULL calibration mode (SIM_BYPASS_INIT_CAL="SIM_INIT_CAL_FULL").


The JEDEC specifications state that a maximum of eight refreshes can be postponed up to 9*tREFI periods, and after that refreshes should be pulled in to meet the tREFI time.

The MIG 7 Series v1.2-v1.4 DDR3 design is violating this specification when SIM_BYPASS_INIT_CAL="SIM_INIT_CAL_FULL".

There is currently no workaround, so these violations can be ignored for now.

This issue is due to be fixed in MIG v1.5 to be released in ISE 14.1.

Linked Answer Records

Master Answer Records

Associated Answer Records

AR# 42832
Date 08/13/2014
Status Active
Type Known Issues
Devices More Less