On-die termination control for memory systems

Abstract

A memory system, comprising: a first plurality of memory ranks each having multiple memory cells; a second plurality of local controllers each coupled between one or more of the first plurality of memory ranks and a memory controller, the memory controller being configured to provide to a target local controller of the second plurality of local controllers, out of a first plurality of chip select (CS) signals, a target access CS signal enabling target access to a target memory rank of the first plurality of memory ranks coupled to the target local controller, and provide to the second plurality of local controllers, later than the target access CS signal, a command and address (CA) signal for addressing and accessing the multiple memory cells of the target memory rank; and wherein the target local controller is configured to generate, in response to receiving the target access CS signal, a target CA on-die termination (ODT) instruction switching on target CA ODT at its CA input at least for a period when the CA signal is being received from the memory controller.