Memory test system having a pattern generator for a multi-bit test

摘要

A semiconductor memory testing methods and apparatus are arranged to accommodate a multi-bit mode of testing operation in which the memory under test itself includes internal peripheral circuits for comparing the contents of memory cells for multi-bit testing, and outputting a single-bit indicative of whether or not said multiple cells have the same state. The present invention includes methods and apparatus for determining the polarity of a memory cell under test, and taking that polarity into account informing expected data to be compared to the output of the memory under test.