US3691541A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Read only memory
Assignee: QUADRI CORP
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Filing: 1971-01-25
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Granted: 1972-09-12
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Expires: 1991-01-25
Abstract
Abstract A read only memory is provided utilizing a plurality of storage cells, each including a cylindrical slug of ferrite material having a read winding thereon: address lines pass between the storage cells and inductively couple the slugs in either a predetermined sense or an opposite sense. An electrostatic shield is provided and a bias winding is inductively coupled to each of the slugs to facilitate error-free reading of the memory contents.
Inventors
- 👤 John F Bruder
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:49
CPC Classifications
G; G11; G11C; G11C17/00; G11C17/02
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
200 words
In a read only memory, the combination comprising: a. a plurality of storage cells, each said cell being a straight bar of ferrite material, having a predetermined number of address lines coupled thereto, each address line inductively coupled to each storage cell through a fractional turn address winding in a predetermined sense to selected ones of said storage cells while inductively coupled in an opposite sense to all other storage cells in accordance with the information stored in said address line; b. a bias winding inductively coupled in said predetermined sense to all of said storage cells and bias switching means for applying a biasing signal to said bias winding, said bias signal coupled to all of said storage cells to reinforce signals applied by said address lines to said selected ones of said storage cells and to oppose signals applied by said address lines to all other storage cells; c. each storage cell having a multiple turn output winding responsive to a signal on one of said predetermined number of address lines for coupling said signal to said output winding; and d. switching means connected to said address lines for selecting an address line and applying a signal thereto.
Claim 2
Dependent Claim
200 words
In a read only memory, the combination comprising: a. a plurality of storage cells, each said cell being a straight bar of ferrite material, having a predetermined number of address lines coupled thereto, each address line inductively coupled to each storage cell through a fractional turn address winding in a predetermined sense to selected ones of said storage cells while inductively coupled in an opposite sense to all other storage cells in accordance with the information stored in said address line; b. a bias winding inductively coupled in said predetermined sense to all of said storage cells and bias switching means for applying a biasing signal to said bias winding, said bias signal coupled to all of said storage cells to reinforce signals applied by said address lines to said selected ones of said storage cells and to oppose signals applied by said address lines to all other storage cells; c. each storage cell having a multiple turn output winding responsive to a signal on one of said predetermined number of address lines for coupling said signal to said output winding; and d. switching means connected to said address lines for selecting an address line and applying a signal thereto.
Claim 3
Dependent Claim
19 words
The combination set forth in claim 1, wherein said substantially straight bar of ferrite material is a cylindrical slug.
Claim 4
Dependent Claim
41 words
The combination set forth in claim 2, including an electrostatic shield comprising a non-magnetic conducting material extending around said output winding; said shieLd insulated from said winding and having an insulating gap therein to prevent said shield from becoming a winding.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-09-12 | 1976-03-13 | 1976-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-12 | 1980-03-13 | 1980-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-12 | 1984-03-13 | 1984-09-12 | $7700.00 | Window Closed / Lapsed |