Method and apparatus for indicating bad memory areas

摘要

Regardless of data values stored on data memory cells, all read operations on the data memory cells are disallowed. For example, current flow is disallowed through a string of the data memory cells and one or more select line memory cells. The particular select value stored in a first select line memory cell in the string, for example coupled to a ground select line or a string select line, determines whether the string is enabled or disabled.

主权项

1. An integrated circuit apparatus, comprising:
a plurality of memory cells arranged between a first end and a second end of a string, the string including data memory cells and one or more select transistors, wherein the one or more select transistors store one of at least a low threshold voltage and a high threshold voltage, wherein at least one of the one or more select transistors stores the high threshold voltage such that said at least one of the one or more select transistors disallows current through the string during a read operation on at least part of the string.