Semiconductor memory device, method of controlling read preamble signal thereof, and data transmission system

摘要

A controller, includes a plurality of external terminals configured to supply a command and an address to a semiconductor memory device, communicate a data with the semiconductor memory device, and communicate a strobe signal related to the data, at least one external terminal among the plurality of external terminals being configured to be capable of supplying an information specifying a length of a preamble of the strobe signal before the semiconductor memory device communicates the data.

主权项

1. A controller, comprising:
a first external terminal configured to correspond to a system clock to which a semiconductor memory device receives; a second external terminal configured to supply a command to the semiconductor memory device; a third external terminal configured to communicate a data with the semiconductor memory device; a fourth external terminal configured to transmit a data strobe signal having a preamble and a toggle transition following to the preamble, the preamble corresponding to a start timing of communicating the data and the toggle transition corresponding to communicating the data between the controller and the semiconductor memory device; and a fifth external terminal configured to be capable of outputting an information specifying a length of the preamble to the semiconductor memory device, the length of the preamble being dynamically changeable between first and second lengths at times after a system start-up time, and wherein the first length corresponds to the information.