Memory module with timing-controlled data buffering

Abstract

A memory module is operable in a memory system with a memory controller. The memory module comprises memory devices, a module control circuit, and a plurality of buffer circuits coupled between respective sets of data signal lines in a data bus and respective sets of the memory devices. Each respective buffer circuit is mounted on the module board and coupled between a respective set of data signal lines and a respective set of memory devices. Each respective buffer circuit is configured to receive the module control signals and the module clock signal, and to buffer a respective set of data signals in response to the module control signals and the module clock signal. Each respective buffer circuit includes a delay circuit configured to adjust the timing of at least one of the respective set of data signals by an amount based on at least one module control signal in a previous operation.