US Patent 8006057 Memory devices with buffered command address bus

Circuits and methods are provided that alleviate overloading of the command address bus and limit decreases in command address bus bandwidth to allow increased numbers of memory modules to be included in a computer system. A plurality of switches is coupled between the command address bus (which is coupled to the memory controller) and a respective plurality of memory modules. Each switch provides command address bus data only to its respective memory module. Preferably, only one switch does so at a time, limiting the loading seen by the memory controller.