Apparatus and methods for determining memory device faults
AssigneePurdue Research Foundation
InventorsQikai Chen, Swarup Bhunia, Hamid Mahmoodi, Kaushik Roy
Life of this patent
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Abstract
A test circuit used for determining a fault in a memory device. The test circuit includes a read circuit configured to read memory cell contents in a memory device at a first time instant and second time instant. The test circuit includes a comparator that compares the contents at the first and second time instants. If the contents are different from one another, the comparator indicates that a fault has occurred. Test methods are also used to determine if a fault has occurred in a memory cell.
Claims19
A test circuit for determining a memory cell fault in a memory device, the test circuit comprising:
- a read circuit configured to read a memory cell and produce a first output indicative of memory cell content at a first time instant and a second output indicative of the memory cell content at a second time instant later than the first;
- and
- a comparator configured to receive and process the first and second outputs and to produce a signal indicative of whether a memory cell fault has occurred.
A static random access memory (SRAM) device comprising:
- a number of memory cells configured to each store bit data content and each being identified by a particular memory address and bit location;
- a number of bit lines, each bit line corresponding to a particular bit location;
- a number of word lines, each word line corresponding to a particular memory address;
- and
- a number of test circuits, each test circuit configured to determine a memory cell fault at a particular bit location and each test circuit comprising:
- a read circuit configured to read a memory cell and produce a first output indicative of memory cell content at a first time instant and a second output indicative of the memory cell content at a second time instant later than the first;
- and
- a comparator configured to receive and process the first and second outputs and to produce a signal indicative of whether a memory cell fault has occurred.
Dependencies are inferred from the claim text.