Excavating
Patent
1985-10-17
1987-07-14
Atkinson, Charles E.
Excavating
365201, 371 21, G01R 3128
Patent
active
046807624
ABSTRACT:
To locate soft cells in a memory cell array, a known logic pattern is written in the memory array. The word lines for the array are then sequentially subjected to a nonstandard test signal such as a slowly varying voltage. Word lines are returned to VCC and the array is then interrogated to identify memory cells which have flipped logic states. These cells are identified as soft or potentially defective cells. The process can be repeated with the logically opposite logic pattern being initially stored in the array. Apparatus is provided for implementing this process on a standard RAM memory cell array. An access pad is added for receipt of an externally generated test signal. A control circuit selectively couples the test signal to the word lines for the memory array.
REFERENCES:
patent: 3478286 (1969-11-01), Dervan III
patent: 3655959 (1972-04-01), Chernow et al.
patent: 4335457 (1982-06-01), Early
patent: 4418403 (1983-11-01), O'Toole et al.
patent: 4481628 (1984-11-01), Pasquinelli
patent: 4527254 (1985-07-01), Ryan et al.
patent: 4553225 (1985-11-01), Che
Marrotte, Tape Phase Error-Detection Measurement, IBM Technical Disclosure Bulletin, vol. 11, No. 10, Mar. 1969, p. 1210.
Hardee Kim C.
Khan Anwar U.
McEuen Steven D.
Wicker, Jr. David J.
Atkinson Charles E.
Inmos Corporation
Manzo Edward D.
Wise Roger R.
LandOfFree
Method and apparatus for locating soft cells in a ram does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for locating soft cells in a ram, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for locating soft cells in a ram will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1431775