Autotesting method of a memory cell matrix, particularly of the non-volatile type

A method for testing of memory cells within a memory matrix, wherein the matrix comprises memory cells arranged in subsets of memory cells, the method comprising:

• (a) reading a value stored in each memory cell in a first subset of memory cells and comparing each read value to a predetermined reference value;
• (b) determining that a defect exists in the first subset if any read value does not match the corresponding reference value;
• and
• (c) storing in memory the location of the first subset of memory cells if it is determined that a defect exists.

A method, comprising:

• reading a first memory location in a first row and a first column;
• comparing the contents of the first memory location with a first predetermined value;
• storing the result of the first comparison in a test location;
• reading a second memory location in a second row and the first column;
• comparing the contents of the first memory location with a second predetermined value;
• storing the result of the second comparison in the test location;
• and
• replacing the first column with a redundant column if the contents of the test location indicate that the first column is defective.

A memory, comprising:

• a matrix having columns of memory cells;
• a pattern generator;
• a comparator coupled to the matrix and the pattern generator and operable to compare the respective contents of each memory cell in one of the columns with a respective test value from the pattern generator;
• and
• a test location coupled to the comparator and operable to store a first value if the contents of each memory cells in the column equals the respective test value and to store a second value if the contents of at least one memory cell in the column does not equal the respective test value.