High-density memory utilizing multiplexers to reduce bit line pitch constraints

Abstract

A memory that includes a plurality of storage blocks. Each block has a plurality of storage cells constructed from a storage element and an isolation transistor. The storage cells in a block are organized as a plurality of rows and column units. Each column unit includes a first bit line and a plurality of the memory cells connected to the first bit line by the isolation transistors in those memory cells. The memory also includes a first multiplexer connected to a plurality of the first bit lines in a first one of the memory blocks, the first multiplexer connecting one of the first bit lines to a first conductor in response to one or more first multiplexer control signals. The first multiplexer is located adjacent to the storage block containing first bit lines connected thereto. The first conductor is connected to a sense amplifier for reading the contents of the storage cells. The sense amplifier may be located adjacent to the first multiplexer or at a remote location relative to the storage block. The memory is particularly adapted for use in stacked memory designs in which the sense amplifiers and control circuitry are located on a different layer from the storage blocks.