SEMICONDUCTOR MEMORY DEVICE, SEMICONDUCTOR MEMORY MODULE AND SEMICONDOCTOR MEMORY SYSTEM COMPRISING THE SAME

摘要

PURPOSE: A semiconductor memory device, a semiconductor memory module and the semiconductor memory system comprising the same are provided to minimize the skew of a command/address signal and a chip selection signal by allowing a command/address reference signal and the chip selection reference signal to have different voltage. CONSTITUTION: In a semiconductor memory device, a semiconductor memory module and the semiconductor memory system comprising the same, a command / address input buffer(310) receives a command / address signal. The command / address input buffer receives a command address reference voltage signal. The command / address input buffer amplifies the difference between the command/address signal and the reference signal of the command/address signal. A chip select input buffer(320) receives a chip select signal and a chip selection reference voltage signal. The chip select input buffer amplifies the chip select signal and the chip select reference voltage signal.