Abstract: A memory device comprising a programmable command-and-address (CA) interface and/or a programmable data interface is described. In an operational mode, two or more CA interfaces may be active. In another operational mode, at least one, but not all, CA interfaces may be active. In an operational mode, all of the data interfaces may be active. In another operational mode, at least one, but not all, data interfaces may be active. The memory device can include circuitry to select: an operational mode; a sub-mode within an operational mode; one or more CA interfaces as the active CA interface(s); a main CA interface from multiple active CA interfaces; and/or one or more data interfaces as the active data interfaces. The circuitry may perform these selection(s) based on one or more bits in one or more registers and/or one or more signals received on one or more pins.

Abstract: A system includes a plurality of memory devices arranged in a fly-by topology, each of the memory devices having on-die termination (ODT) circuitry for connection to an address and control (RQ) bus. The ODT circuitry has at least one input for controlling termination of one or more signal lines of the RQ bus. Application of a first logic level to the at least one input enables termination of the one or more signal lines. Application of a second logic level to the at least one input disables termination of the one or more signal lines.

Abstract: A system includes a plurality of memory devices arranged in a fly-by topology, each of the memory devices having on-die termination (ODT) circuitry for connection to an address and control (RQ) bus. The ODT circuitry has at least one input for controlling termination of one or more signal lines of the RQ bus. Application of a first logic level to the at least one input enables termination of the one or more signal lines. Application of a second logic level to the at least one input disables termination of the one or more signal lines.