Integrated circuit memory devices having control circuits therein that provide column redundancy capability

Abstract

Preferred memory devices include a first bit line within a first block of memory and a second bit line within a second block of memory. The first bit line is electrically coupled to a reference voltage signal line by a pull-up transistor that turns on in response to an active first bit line pull-up signal (e.g., /BLPU_IOn=0). The second bit line is also electrically coupled to the reference voltage signal line by a pull-up transistor that turns on in response to an active second bit line pull-up signal (e.g., /BLPU_IOn+1=0). A control circuit is provided and this control circuit is responsive to a multi-bit shift signal. The control circuit disables generation of the active first bit line pull-up signal in favor of an active second bit line pull-up signal when a value of the shift signal designates replacement of the first block of memory with the second block of memory. The control circuit may also generate signals that disconnect a first IO line associated with a defective first block of memory and substitute a second IO line associated with a functional second block of memory for the first IO line.