System having one or more memory devices

摘要

A system having serially connected memory devices in a ring topology organization to realize high speed performance. The memory devices have dynamically configurable data widths such that the system can operate with up to a maximum common number of active data pads to maximize performance, or to operate with a single active data pad to minimize power consumption. Therefore the system can include a mix of memory devices having different data widths. The memory devices are dynamically configurable through the issuance of a single command propagated serially through all the memory devices from the memory controller in a broadcast operation. Robust operation of the system is ensured by implementing a data output inhibit algorithm, which prevents valid data from being provided to the memory controller when read output control signal is received out of its proper sequence.

主权项

1. A system comprising:
a memory controller having a first number of output ports, the memory controller operable to provide a command to access data width configuration data representing a data width, from one output port of the first number of output ports; and, a memory device coupled to the memory controller in a ring topology, the memory device having an input/output register operable to store the data width configuration data, a second number of data input pads, and the second number of data output pads, the memory device operable to provide the data width configuration data from one data output pad of the second number of data output pads in response to receiving the command at one data input pad of the second number of data input pads; wherein the memory controller is further operable to receive the data width configuration provided by the memory device.