Semiconductor memory device with hierarchical bit line structure

Abstract

A semiconductor memory device has a hierarchical bit line structure. The semiconductor memory device may include first and second memory cell clusters, which share the same bit line pair and are divided operationally; third and fourth memory cell clusters, which are connected respectively corresponding to word lines coupled with the first and second memory cell clusters, and which share a bit line pair different from the bit line pair and are divided operationally; and a column pass gate for switching one of bit line pairs connected with the first to fourth memory cell clusters, to a common sense amplifier, in response to a column selection signal. Whereby an operating speed decrease caused by load of peripheral circuits connected to the bit line is improved, and the number of column pass gates is reduced substantially with a reduction of chip size.