Device Family: Intel® Arria® 10, Intel® Stratix® 10

Type: Answers

Area: EMIF


Last Modified: July 20, 2017
Bug ID: FB: 477716;
IP: Arria 10 External Memory Interfaces, Stratix 10 External Memory Interfaces

How should the CKE signal be terminated for DDR3 and DDR4 interfaces?

Description

The CKE signal is pulled down to GND on the DDR3 HiLo daughter card and terminated with a thevenin parallel termination on the DDR4 HiLo daughter card.

Workaround

All address and command signals including the CKE signal should use a fly-by termination for Arria®10 and Stratix®10 DDR3 and DDR4 interfaces. These signals should be terminated with a resistor to VTT at the end of the fly-by topology. This termination is required only for discete memory device implementations and is not required for DIMMs.