Abstract:
A monolithic storage matrix having cells formed of multi-emitter transistors in which one emitter of each transistor forms part of the storage circuit and the other emitter of each transistor is coupled to the accessing and retrieval circuits. The transistors portions for storage are formed with bases of a given width and the transistors portions coupled to the accessing and retrieving circuits have a lesser width so that short access times are obtained while the stability of the storage circuit is maintained.
Abstract:
A monolithic storage arrangement comprising a plurality of cross-coupled bipolar transistor bistable storage cells selectively operable both as a read-write storage and as a readonly storage. The switching nodes of each storage cell are connected to respective switching bipolar transistors which are complementary with respect to the cross-coupled transistors, the collector-base section of the switching transistors being connected in parallel with the base-emitter section of the respective cross-coupled transistors. For read-only operation, the emitter of one of the switching transistors is connected to a control line with the emitter of the other switching transistor remaining unconnected in accordance with predetermined fabrication personalization. The connected switching transistor injects current into the base of its associated cross-coupled transistor when the control line is suitably energized to place the cell into a desired read-only state. Both switching transistors are deactivated during read-write operation.
Abstract:
A monolithic storage arrangement comprising a plurality of symmetrically disposed bistable storage cells operable both as read/write and read-only elements.
Abstract:
1,245,368. Semiconductor devices. INTERNATIONAL BUSINESS MACHINES CORP. 28 March, 1969 [30 April, 1968], No. 16392/69. Heading H1K. [Also in Division H3] In a monolithic integrated circuit two transistors are formed in a common epitaxial region, which forms a part of each transistor, by means of separate diffused regions, the transistors being connected in a circuit so that in operation the common region functions as the emitter of at least one of the transistors. The transistors are formed simultaneously by diffusing P-type base regions into an N-type epitaxial layer on a P+-type substrate, the epitaxial layer being divided into islands by a P-type isolation diffusion. N-type regions are diffused into the base regions and form the emitters of normally poled transistors and the collectors of inversely poled transistors. The inversely poled transistors exhibit a low gain which may be less than unity if the circuit is gold doped. A memory cell, Fig. 3, comprises five transistors T1 to T5 and two resistors R1 and R2, two of the transistors T3, T4, forming a bi-stable multivibrator, being arranged in a single island and operated so that the common region functions as their emitters, and the other three transistors T1, T2, T5, forming addressing, reading and writing components, being arranged in a second island and operated so that the common region forms the emitters of two of the transistors T1, T2 and the collector of the third transistor T5.