US3711839A - High density core memory matrix - Google Patents

High density core memory matrix Download PDF

Info

Publication number
US3711839A
US3711839A US00165477A US3711839DA US3711839A US 3711839 A US3711839 A US 3711839A US 00165477 A US00165477 A US 00165477A US 3711839D A US3711839D A US 3711839DA US 3711839 A US3711839 A US 3711839A
Authority
US
United States
Prior art keywords
cores
core
row
along
longitudinal
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00165477A
Other languages
English (en)
Inventor
V Sell
S Alvi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ampex Corp
Original Assignee
Ampex Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ampex Corp filed Critical Ampex Corp
Application granted granted Critical
Publication of US3711839A publication Critical patent/US3711839A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11C—STATIC STORES
    • G11C7/00—Arrangements for writing information into, or reading information out from, a digital store
    • G11C7/02—Arrangements for writing information into, or reading information out from, a digital store with means for avoiding parasitic signals

Definitions

  • ABSTRACT A high density core memory matrix has cores spaced very close together along longitudinal axes and moderately close along latitudinal axes. The close longitudinal spacing is facilitated by orienting the cores at the maximum acute angle with respect to the longitudinal axis consistent with proper passage of the latitudinal drive lines. Undesirable electrical characteristics and propagation-time delays are minimized by passing the sense and inhibit lines along the extremely compacted longitudinal axis.
  • the cores are located on centers which are at least spaced one diameter apart in both the longitudinal and latitudinal directions.
  • the cores are located at an angle of 45 to bisectthe angle between the longitudinal and latitudinal axes thus permitting diagonal threading of the sense lines to balance the partial excitation noise signals and obtain mutual cancellation.
  • An improved high density core arrangement is attained by arranging a matrix of magnetic cores in a double herringbone pattern wherein two adjacent longitudinal rows of cores have the same orientation to form a similarly oriented pair of rows. Adjacent row pairs have opposite orientations.
  • the cores are oriented at a nonbisecting acute angle greater than 45 with respect to the longitudinal axis and are greatly compacted, thereby permitting a sense line located along this longitudinal axis to be much shorter.
  • the cores are located on centers spaced approximately one-half diameter apart along the longitudinal axis and approximately one diameter apart along the latitudinal axis.
  • the cores are oriented at an angle of 50 with respect to the longitudinal axis to accommodate this spacing.
  • This closely packed double herringbone arrangement provides many additional advantages.
  • the bit density is doubled and the signal propagation time is greatly reduced. This is particularly important in large memory planes where it is desirable to have a constant access time regardless of core position. Additional advantages are gained from a decrease in the capacitance between the sense line and the drive lines and a decrease in the self inductance of the sense line. These factors, which are largely dependent upon the length of the sense and drive lines greatly decrease the amount of disturbance on the sense line as well as the amount of drive power that is required. Further, the close positioning of the cores along the longitudinal axes produces a tunneling or magnetic shielding effect. The spacing between cores is so small that the cores overlap and very little magnetic flux is able to escape the tunnel to couple with an adjacent row. Thus inductive coupling between wires in adjacent rows may be reduced as much as to 1.
  • Another advantage of the close spacing technique is manifested as the wires are threaded through the cores during manufacture.
  • a needle is used to thread the various wires through the cores and it frequently happens that the needle point gouges or chips a piece of core material from one of the cores. This results in a defective core which must be replaced.
  • a needle is more closely constrained to the path through the core centers and needle damage is substantially reduced.
  • FIG. 1 is a schematic representation of a portion of a core memory matrix arranged in accordance with the invention
  • FIG. 2 is an enlarged, sectional view of a portion of the core memory matrix shown in FIG. 1, illustrating the preferred angle of orientation and spacing of magnetic cores.
  • a high density core memory matrix in accordance with the invention utilizes a double herringbone pattern with cores positioned on centers less than one diameter apart and oriented at an acute angle greater than 45 with respect to longitudinal axes.
  • the core spacing is particularly compressed along the longitudinal axes and the length of a sense line is minimized by running it parallel to the longitudinal axes.
  • a high density core memory matrix in accordance with the invention has a substrate 12 with a matrix of magnetic cores 14 bonded thereto.
  • the matrix in this example forms a memory plane having 16,384 cores with 128 cores in each row and each column.
  • the example of FIG. 1 uses a 3-wire arrangement with an X or longitudinal drive line 16, a Y or latitudinal drive line 18 and a sense-inhibit line 20 inductively coupling each core.
  • this high density technique is equally applicable to other wiring arrangements such as those having 2 or 4 wires coupling each core.
  • the cores 14 are standard sized 18 mil cores having an outside diameter of 0.0178-inches, an inside diameter of 0.01 17 inches and a width of 0.0042 inches. They are positioned in a double herringbone pattern in which two adjacent longitudinal rows of cores have a similar orientation to form a row pair and the cores of adjacent row pairs have opposite orientations. Minimal spacing along the longitudinal axis is attained by orienting the cores at the maximum angle consistent with threading of the latitudinal drive wire, 18 in this example.
  • the core orientations may be reversed at selected intervals along each row pair and the sense-inhibit lines, which extend along the rows, may cross from one row in a row pair to the other.
  • the cores in the lefthand portion of row pair X X which intersect column windings Y Y have an opposite orientation from those in the righthand portion which intersect column windings Y Y
  • the number of core orientation reversals or sense-inhibit line crossovers can be increased if desired.
  • a senseinhibit line 20 passes through each of the cores in the longitudinal direction.
  • This sense-inhibit line 20 has two symmetrical halves labeled S-Ia and S-Ib which are connected at center tap 22.
  • Each core in each row pair is coupled to one of the two halves of the sense-inhibit line 20 while the corresponding cores in the pairing row are inductively coupled to the other half.
  • each core in the matrix is inductively coupled to one of the two halves of the sense line.
  • the center tap 22 is connected to an inhibit wire 24 which in turn is connected by a switch 26 to a current sink or driver (not shown).
  • a switch 26 to a current sink or driver (not shown).
  • the sense-inhibit line 20 functions as a single balanced sense line with the switch 26 open and during a write operation the sense-inhibit line functions as two parallel inhibit lines with the switch 26 closed.
  • similarly oriented groups of rows may contain four rather than two rows and different sizes of drive and sense wires may be used.
  • the use of smaller latitudinal drive lines may permit a somewhat greater angle of orientation, thereby decreasing the threading aperture," but also enabling a closer spacing along the longitudinal axes.
  • FIG. 2 shows several cores 14 from the example shown in FIG. 1 at the intersection of the drive line pair X X with latitudinal drive lines Y Y and Y It can be seen that as the two drive wires and the sense-inhibit wire intersect at a core 14 the Y drive line passes between the X drive line and the sense-inhibit line. This affords a Y drive line an optimum aperture" as it passes through the cores in a column.
  • the 18 mil cores 14 used in this example are located on center points which are spaced a distance A 0.0167 inch apart along the latitudinal axes between rows which are similar oriented and form a row pair. Between rows which are oppositely oriented the spacing is B 0.0181 inch. The longitudinal spacing between the center points is C 0.010 inch between cores which are similarly oriented and 0.0181 inch at the crossover point of the sense-inhibit line between drive lines Y. and Y In this example the X and Y lines have diameters of 0.0027 inch and the sense-inhibit line has a diameter of 0.0029 inch.
  • the magnetic cores provide a tunneling or shielding effect which greatly reduces magnetic coupling between wires in adjacent rows. For instance, in trying to visualize vertical paths connecting drive line X with a portion of the sense-inhibit line in row X it can be seen that these vertical paths are substantially limited to the apertures through which the Y drive lines pass. This shielding reduces inductive coupling between rows by a factor of 10 or more.
  • the constraints which apply to the orientation of a magnetic core are illustrated in conjunction with the core which appears at the intersection of drive lines X and Y in FIG. 2. As shown therein the core is oriented at an angle a with respect to its longitudinal axis and has a vertical opening or aperture 40 with a width D for receiving drive line Y The core has an outside diameter D an inside diameter D,- and a width W.
  • the width D of the aperture 40 should be nearly double the diameter of the latitudinal drive line Y
  • a right triangle having vertices 44, 45, 46 is formed. It can be seen that the angle at vertex 45 is the angle at vertex 44 is 0 90 a and the angle at vertex 46 is a. It can be further seen from this arrangement that:
  • the capacitive coupling between the parallel sense-inhibit and X drive lines is given the formula 1rE1 cash- (d/a) 4 where CAP capacitance, E permittivity of the dielectric between the two lines, 1 length of the parallel line in meters, d separation between the two lines in meters and a diameter of the wires in meters.
  • N is the number of cores in a longitudinal, row, N,,,,, is the number of cores in a latitudinal column
  • A is the latitudinal spacing between core center points in similarly oriented rows
  • B is the latitudinal spacing between core center points in oppositely oriented rows
  • C is the longitudinal spacing between cores.
  • the sense line length for these arrangements has an additional factor of V2 because it connects diagonali rather than adjacent cores. This results in a shortening of the sense line length by approximately 2 V2as com-; pared to diagonal sense lines. It can thus be seen from equation (4) that the present arrangement reducesi capacitive coupling by nearly 2 and 2 V2 over previ-i ously known arrangements.
  • signal delay, 7 is proportional to V L(CAP)l where L is the inductance of the line in hen ties/meter and equals [.L/IT cosh (d/a)1, and where p. is
  • a core memory comprising: a plurality of magnetic cores disposed along a lon-' gitudinal axis to form a row of cores similarly oriented at an acute angle substantially greater. than 45 with respect to the longitudinal axis, said cores being positioned about center points having a spacing between them less than the outside diameter of core;
  • said detecting means is a sense wire extending along the longitudinal axis and inductively coupling all; of the cores in the row.
  • a core memory matrix comprising:
  • each row having at least one group of a plurality of adjacent cores which are similarly oriented at an acute angle greater than 45 with respect to the longitudinal axis of the row and which are spaced about center points separated by substantially less than outside diameter of a core along the longitudinal axis of the row;
  • the switching means includes a plurality of column drive lines, each inductively coupling all of the cores in a column and a plurality of row drive lines, each inductively coupling all of the cores in a row; and wherein the detecting means includes at least one. sense line positioned parallel to the row drive lines and inductively coupling at least a portion of the cores in at least one row.
  • a core memory matrix comprising a plurality of magnetic cores arranged in a double herringbone pattern having latitudinal and longitudinal axes, said cores being positioned about center points having a spacing of substantially less than an outside core diameter between them along the longitudinal axes.
  • latitudinal drive means inductively coupling each core along a latitudinal axis
  • longitudinal drive means inductively coupling each core along a longitudinal axis
  • sense means inductively coupling at least a plurality of the cores along a longitudinal axis.
  • a magnetic core memory matrix comprising:
  • each of said cores being disposed at an acute angle substantially greater than 45 with respect to the X axis;
  • X and Y drive wires disposed orthogonally through said matrix with one X and Y wire coupling each different one of said cores, said cores having different spacings along the X and Y axes and having greater density along the X axis.
  • a high density core memory matrix comprising:
  • a plurality of magnetic cores positioned on the substrate in a double herringbone pattern with rows of cores defining longitudinal axes and columns of cores defining latitudinal axes, the cores being oriented at an acute angle greater than 45 with respect to the longitudinal axes and positioned about centers having a spacing of substantially less than the outside diameter of a core between them along the longitudinal axis;
  • latitudinal drive means inductively coupled to each core for providing each core in a selected column a partial select current
  • longitudinal drive means inductively coupled to each core for providing each core in a selected row a partial select current, the combined column and row partial select currents being sufficient to.
  • a core memory comprising:
  • a plurality of magnetic cores disposed along a plurality of pairs of longitudinal axes to form row pairs, said cores being oriented at an acute angle substantially greater than 45 with respect to the longitudinal axes with all cores in a row pair being similarly oriented and cores in adjacent row pairs being oppositely oriented;
  • ' means extending along the longitudinal axis of at least one row and inductively coupling all of the cores in the row for selectively sensing and inhibiting the switching of inductively coupled cores.
  • a core memory plane comprising:
  • each row having at least one group of cores similarly oriented at an acute angle substantially greater than 45 with respect to its longitudinal axis, the rows being grouped into pairs of adjacent rows having cores similarly oriented, the cores of adjacent pairs being oppositely oriented;
  • latitudinal drive means inductively coupling a half select current to all of the cores of a selected column
  • longitudinal drive means inductively coupling a half select current to all of the cores of a selected row
  • a sense line extending along the rows of cores and inductively coupling each core in the plane.
  • a core memory comprising: a plurality of magnetlc cores disposed along a longitudinal axis to form a row of cores similarly oriented at an acute angle greater than 47 with respect to the longitudinal axis, said cores being positioned about center points having a spacing between them less than the outside diameter of a core;
  • a core memory matrix comprising:
  • a plurality of magnetic cores having two stable states and arranged in rows along longitudinal axes and columns along latitudinal axes, each row having at least one group of a plurality of adjacent cores which are similarly oriented and which are spaced about center points separated by less than percent of the outside diameter of a core along the longitudinal axis of the row;

Landscapes

  • Magnetic Heads (AREA)
  • Coils Or Transformers For Communication (AREA)
  • Semiconductor Memories (AREA)
  • Mram Or Spin Memory Techniques (AREA)
US00165477A 1971-07-26 1971-07-26 High density core memory matrix Expired - Lifetime US3711839A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US16547771A 1971-07-26 1971-07-26

Publications (1)

Publication Number Publication Date
US3711839A true US3711839A (en) 1973-01-16

Family

ID=22599057

Family Applications (1)

Application Number Title Priority Date Filing Date
US00165477A Expired - Lifetime US3711839A (en) 1971-07-26 1971-07-26 High density core memory matrix

Country Status (9)

Country Link
US (1) US3711839A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
JP (1) JPS5648909B1 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
BE (1) BE786689A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
CA (1) CA931659A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
DE (1) DE2236694B2 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
FR (1) FR2147158B1 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
GB (1) GB1347960A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
IT (1) IT961652B (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)
SE (1) SE371709B (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3864672A (en) * 1972-07-12 1975-02-04 Philips Corp Matrix store wiring pattern
US3872454A (en) * 1973-12-13 1975-03-18 Electronic Memories & Magnetic Skewed core matrix
US20110117733A1 (en) * 2009-11-19 2011-05-19 Scott Sills Methods Of Utilizing Block Copolymers To Form Patterns

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3085314A (en) * 1957-09-30 1963-04-16 Ibm Method of making a core plane assembly

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3085314A (en) * 1957-09-30 1963-04-16 Ibm Method of making a core plane assembly

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
IBM Technical Disclosure Bulletin Vol. 3, No. 1, June 1960, pg. 45. *
IBM Technical Disclosure Bulletin Vol. 3, No. 10, Mar. 1961, pgs. 105 106. *

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3864672A (en) * 1972-07-12 1975-02-04 Philips Corp Matrix store wiring pattern
US3872454A (en) * 1973-12-13 1975-03-18 Electronic Memories & Magnetic Skewed core matrix
US20110117733A1 (en) * 2009-11-19 2011-05-19 Scott Sills Methods Of Utilizing Block Copolymers To Form Patterns
US8268732B2 (en) 2009-11-19 2012-09-18 Micron Technology, Inc. Methods of utilizing block copolymers to form patterns
US8518835B2 (en) 2009-11-19 2013-08-27 Micron Technology, Inc. Methods of utilizing block copolymers to form patterns

Also Published As

Publication number Publication date
FR2147158B1 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) 1977-01-14
JPS5648909B1 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) 1981-11-18
CA931659A (en) 1973-08-07
IT961652B (it) 1973-12-10
FR2147158A1 (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) 1973-03-09
SE371709B (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) 1974-11-25
GB1347960A (en) 1974-02-27
DE2236694A1 (de) 1973-02-08
BE786689A (fr) 1972-11-16
DE2236694B2 (de) 1976-04-15

Similar Documents

Publication Publication Date Title
US8755220B2 (en) Hybrid superconducting-magnetic memory cell and array
EP0262780A1 (en) Marching interconnecting lines in semiconductor integrated circuits
US3711839A (en) High density core memory matrix
KR100300047B1 (ko) 노이즈 간섭 방지를 위한 데이터라인 배열 구조를 갖는 반도체 메모리 소자
US3456250A (en) Removable magnetic data storage system
US6885576B2 (en) Closed flux magnetic memory
US3371327A (en) Magnetic chain memory
US6310399B1 (en) Semiconductor memory configuration with a bit-line twist
US3214740A (en) Memory device and method of making same
TWI278097B (en) Semiconductor memory with random access with reduced signal overcoupling
US3460114A (en) Plated wire memory plane
US3550099A (en) Data-storage apparatus
US3172086A (en) Cryoelectric memory employing a conductive sense plane
US3786448A (en) Multiple access plated wire memory
US3238512A (en) Dual element superconductive memory
US3643239A (en) Method of reducing bit line to bit line coupled noise in a plated wire memory stack
US3381282A (en) Core matrix winding pattern
US3383665A (en) Thin-film memory with two output lines
US3740481A (en) Sense line coupling structures circuits for magnetic memory device
GB1090133A (en) Improvements relating to information storage devices
US3905026A (en) Large, high speed two dimensional core memory
US3206733A (en) Memory systems having flux logic memory elements
US3739361A (en) Magnetic thin film memory plane
US3484761A (en) Pulse transformers comprising stacked ferrite blocks
KR100379045B1 (ko) 기록소자와판독소자가제공된자기헤드