Content-addressable memory with soft-match capability

Static information storage and retrieval – Associative memories – Ferroelectric cell

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Details

364200, 3642531, 3642592, G11C 1500

Patent

active

050539914

ABSTRACT:
Each word location (18-0, 18-1, 18-255) in a content-addressable memory has a tally circuit (24-0, 24-1, 24-255) associated with it. A data word on data lines (12) is compared simultaneously with the words in all of the word locations, and the tally circuit associated with each location counts the number of matches between the key word in that location and the data word represented by the signals on the data line. The tally circuits apply tally signals representing the number of matching bits in their respective word locations to comparison circuits (28-1, 28-255), each of which compares the tally output from its associated tally circuit with the output from a previous comparison circuit and forwards the higher of the two to the next comparison circuit. Each comparison circuit also applies to a priority encoder (32) an output that indicates whether the associated tally circuit has generated a tally signal representing a tally greater than that from all previious locations. The encoder circuit (32) encodes the address of the location having the highest tally, and the output of the last comparison represents the highest tally is. In this manner, the content-addressable memory (10) can be addressed by the closest match, not only by an exact match.

REFERENCES:
patent: 3372381 (1968-05-01), Raspanti
patent: 3430203 (1969-02-01), Crawford
patent: 3435422 (1969-03-01), Gerhardt et al.
patent: 3533072 (1967-10-01), Clapper
patent: 3535693 (1970-10-01), Connelly
patent: 3596258 (1971-07-01), Choate et al.
patent: 3613084 (1971-10-01), Armstrong
patent: 3700865 (1972-10-01), Taylor
patent: 3716840 (1973-02-01), Masten et al.
patent: 3725875 (1973-04-01), Choate et al.
patent: 3868655 (1975-02-01), Filippazzi
patent: 3878542 (1975-04-01), Myer
patent: 3934231 (1976-01-01), Armstrong
patent: 3949368 (1976-04-01), West
patent: 3949369 (1976-04-01), Churchill, Jr.
patent: 3969707 (1976-07-01), Lane et al.
patent: 4010452 (1977-03-01), Cazanove
patent: 4056845 (1977-11-01), Churchill, Jr.
patent: 4062001 (1977-12-01), Baker
patent: 4068305 (1978-01-01), Cutler
patent: 4075689 (1978-02-01), Berkling
patent: 4084235 (1978-04-01), Hirtle et al.
patent: 4084260 (1978-04-01), Fleming et al.
patent: 4164025 (1979-03-01), Dubnowski et al.
patent: 4254476 (1981-03-01), Burrows
patent: 4296475 (1981-10-01), Nederlof et al.
patent: 4327407 (1982-04-01), Burrows
patent: 4342093 (1982-07-01), Miyoshi
patent: 4366551 (1982-12-01), Holtz
patent: 4374412 (1983-02-01), Schaffner
patent: 4377855 (1983-03-01), Lavi
patent: 4385371 (1983-05-01), Shafer et al.
patent: 4456976 (1984-06-01), Savage
patent: 4458310 (1984-07-01), Chang
patent: 4464732 (1984-08-01), Clark
patent: 4475194 (1984-10-01), LaVallee et al.
patent: 4484266 (1984-11-01), Becker et al.
patent: 4494191 (1985-01-01), Itoh
patent: 4504907 (1985-03-01), Manning et al.
patent: 4507748 (1985-03-01), Cotton
patent: 4513374 (1985-04-01), Hooks, Jr.
patent: 4523301 (1985-06-01), Kadota et al.
patent: 4527249 (1985-07-01), Van Brunt
patent: 4532606 (1985-07-01), Phelps
patent: 4538243 (1985-08-01), Zehner
patent: 4546428 (1985-10-01), Morton
patent: 4559618 (1985-12-01), Houseman et al.
patent: 4575798 (1986-03-01), Lindstrom et al.
patent: 4580215 (1986-04-01), Morton
patent: 4583169 (1986-04-01), Cooledge
patent: 4622653 (1986-11-01), McElroy
patent: 4627024 (1986-12-01), Whalen et al.
patent: 4630234 (1986-12-01), Holly
patent: 4660166 (1987-04-01), Hopfield
patent: 4670858 (1987-06-01), Almy
patent: 4755974 (1988-07-01), Yamada et al.
patent: 4897814 (1990-01-01), Clark
Wade, J. P. and C. G. Sodini, "Dynamic Cross-Coupled Bitline Content Addressable Memory Cell for High Density Arrays", IEEE International Electron Devices Meeting, 1985.

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