GB1276762A - Memory devices - Google Patents

Abstract

1276762 Read only memory SOC ALSACIENNE DE CONSTRUCTIONS ATOMIQUES DE TELECOMMUNICATIONS ET D'ELECTRONIQUE 3 March 1970 [3 March 1969] 10179/70 Heading G4A Read only memory has a common support having a base 20 of a magnetic material such as a ferrite one face 20<SP>1</SP> of which carries a matrix array of electro-magnetic field generating regions 21 substantially surrounded by conductor interrogation loops 24 each having a pair of half loops. The loops in each column are connected in series and are coupled to a diode 23 at one end and to column amplifiers 26, 26<SP>1</SP>, 26<SP>11</SP>, 26<SP>111</SP> and to row amplifier 27. The opposite face of the base is covered with a metallic layer acting as a screen. A matrix array of electro-magnetic field sensing regions substantially surrounded by read-out loops 24 similarly to the interrogation loops is mounted on the face 20<SP>1</SP> and separated from the other matrix by an insulator. The loops of the read out columns are connected in series and the columns extend perpendicular to the rows of the interrogation matrix. A coupling sheet 3 having a ferrite base 28 has one face 28<SP>1</SP> entirely metallized and has the other face 28<SP>11</SP> contiguous with base 20 during read out. Face 28<SP>11</SP> is metallized but has openings 29 in the metallization, the openings representing binary 1 and being aligned with and having slightly larger dimensions than the regions. The coupling sheet may be split into elements each representing a binary word and may be marked to indicate the nature of the word and each plate may have a metallic screening layer on all four edges. A further embodiment (Fig. 4, not shown) has conductors on flexible sheets folded in zig-zag fashion arranged on supports and having coupling plates held on the supports and inserted in the folds of the sheets. The coupling plates may be marked to indicate their contents.