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US3691541A Expired / Lapsed US ⏱️ 0.0 years remaining

Read only memory

Assignee: QUADRI CORP
•
Filing: 1971-01-25
•
Granted: 1972-09-12
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Expires: 1991-01-25
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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.

References Cited (Backward Citations)

US3175200A Cited
US3215992A Cited
US3396373A Cited
US3295110A Cited
US3488641A Cited
US3496556A Cited
US3461439A Cited
US3535690A Cited

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

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