For Versions Earlier than 14.0, Problems May Occur With DDR3 LRDIMM Interfaces on Stratix V Devices

Device Family: Stratix® V

Type: Answers, Errata

Area: EMIF, Intellectual Property

Description

This problem affects products on Stratix V devices, targeting DDR3 LRDIMMs, with versions of the Quartus II software earlier than 14.0.

DDR3 LRDIMM interfaces on Stratix V devices may not reliably operate at frequencies above 533 MHz.

Also, if you are using half-rate mode or are targeting a multi-slot LRDIMM configuration, a patch is required to ensure proper assertion of ODT.

Workaround/Fix

The workaround for these issue is as follows:

For DDR3 LRDIMM interfaces on Stratix V devices, install version 14.0 or later of the Quartus II software to ensure reliable interface operation at frequencies above 533 MHz.
For DDR3 LRDIMM interfaces on Stratix V devices using half-rate mode or targeting a multi-slot LRDIMM configuration, contact Altera for a patch to modify the assertion of ODT for multi-DIMM topologies and half-rate modes.

These issues are fixed in a future version.