Memory system, semiconductor memory device, and wiring substrate

Abstract

A memory system includes a plurality of semiconductor memory devices each including a termination resistance circuit that can be controlled to be turned on or off from an outside by a termination resistance control signal, and a memory controller. The memory controller includes a termination resistance control unit that outputs the termination resistance control signal so that when a read command or a write command is executed on one of the semiconductor memory devices, termination resistances of all of the semiconductor memory devices are turned on, and when any of the semiconductor memory devices does not execute the read command or the write command, the termination resistances of all of the semiconductor memory devices are turned off. The termination resistance circuit of one of the semiconductor memory devices is turned off, irrespective of the level of the termination resistance control signal when the one of the semiconductor memory devices outputs data in response to the read command.

Dependencies are inferred from the claim text.