摘要:
A field programmable gate array, comprises: a plurality of circuit blocks each having logic circuits; at least one spare circuit block having logic circuits; a set of interconnections including at least one interconnection for connecting at least one of the circuit blocks and the at least one spare circuit programmably; and at least one connecting element disposed on the interconnection of the set of interconnections which turns its status from a turned-on state to a turned-off state or vice versa when programmed. When any one of the circuit blocks is defective, since the defective circuit block can be replaced with the spare circuit block, it is possible to retain any desired functions of the logic circuits by programming the connecting means, thus improving the production yield of the field programmable gate array and thereby reducing the manufacturing cost thereof.
摘要:
A field programmable gate array comprises: a first wire group (8) composed of a plurality of first wires; a second wire group (7) composed of a plurality of second wires; switching sections (9) provided at least one intersection between the first and second wires of the first and second wire groups (8, 7), for determining connection and disconnection between both when programmed; and a basis cell (6B) having a first transmission gate (4) turned on in response to a high gate voltage and a second transmission gate (5) turned on in response to a low gate voltage, gates of the first and second transmission gates (4, 5) being connected to each other as a common gate or being connectable to each other as a common gate by the switching sections when programmed, input and output terminals and the common gates of the first and second transmission gates (4, 5) being connected to any of the first wires of the first wire group (8), respectively. Wiring of different lengths is provided for connecting circuit elements within the field programmable gate array, with wires of a first length being more numerous than wires of a second, longer length. The quantity of wires of different lengths varies in accordance with the -2.5 power of the length of the wires.
摘要:
A single-port memory or a multi-port memory with a higher density than conventional memory devices is realized, while using the same design rule, by decreasing the number of bit lines per column or port to decrease the space for wiring and the size of the entire memory. A memory circuit includes a memory cell array arranging a plurality of memory cells in a matrix, each memory cell having at least one read port; word lines each connected to memory cells aligned in a row among the memory cells of the memory cell array, and bit lines each connected to memory cells aligned in n rows (n.gtoreq.2) among the memory cells of the memory cell array. Current drivability of access transistors of memory cells sharing n bit lines are set to satisfy the relation of 1:2: . . . :2.sup.n-1. This results in decreasing the number of bit lines and the area of the memory.
摘要:
A field programmable gate array comprises: a first wiring group composed of a plurality of first wirings (C1, C2, C3, . . . ); a second wiring group composed of a plurality of second wirings (R1, R2, R3, . . . ); a plurality of programmable elements (A11, A12, A13, . . . ) arranged into an array pattern at at least one of plural intersections between the first wirings and the second wirings, each of the programmable element being connected to each of the first wirings (C1, C2, C3, . . . ) at one end thereof and to each of the second wirings (R1, R2, R3, . . . ) at the other end thereof and being programmed by a programming voltage applied between the first wiring and second wiring to switch connection between the first and second wirings to disconnection between the two wirings or vice versa; and voltage supplying sections (CD1, RD1) for applying a programming voltage between the first and second wirings (C1, C2, C3, . . . ; R1, R2, R3, . . . ) between which the programmable element to be programmed is connected and an intermediate voltage between the first and second wirings between which the programmable element not to be programmed is connected, the intermediate voltage being lower than the programming voltage to such an extent as not to affect state of the programmable elements (A11, A12, A13, . . . ).
摘要:
This invention provides a refresh operation control circuit for a semiconductor memory device. Two flip-flop circuits respectively temporarily hold a normal read start command signal and a refresh start command signal generated within the memory device. A normal operation/refresh operation priority determining circuit wherein 2-input logic circuits are cross-connected so that one output in each case of each of these two flip-flop circuits provides one input of the other flip-flop circuit. The priority determining circuit determines the priority of normal read operation and refresh operation in accordance with the logic level relationship of the one inputs. Either control of the start of normal read operation or control of the start of refresh operation is carried out in accordance with the output of this determination.
摘要:
A dynamic read/write memory in which refreshing is performed within a read/write cycle so that write recovery time is not prolonged. A word line corresponding to a current address is continuously rendered operative within a write period. When a write operation is completed, the word line is rendered operative so that refreshing is initiated. A word line is rendered operative only within a given period of a read period.
摘要:
The invention discloses a semiconductor memory device possessing high operational reliability. In the semiconductor memory device according to the invention, a plurality of well regions of a conductivity type different from that of a semiconductor substrate are formed in the semiconductor substrate, and a memory cell array and a bit line driver are formed in other well regions, situated away from each other. With this arrangement, the number of signal lines to be connected to the well region in which the memory cell array is formed can be reduced, and the adverse influence of minority carriers generated upon operation of the bit line driver can be prevented. With this arrangement, well bias can be applied only to memory cell array. As a result, the operational reliability of the semiconductor memory device can be improved.
摘要:
A virtual type static semiconductor memory device according to the present invention comprises a refresh detector circuit for detecting the enabling operation of a refresh control circuit and a terminal for outputting to an outside a detection signal which is generated from the refresh detector circuit. The virtual type static semiconductor memory device informs a present refresh operation to the outside when it is accessed from the outside during the time period in which a refresh operation is conducted in the semiconductor memory device. A system employing the semiconductor memory device allows a slow access at that time only and allows access to be gained to the semiconductor memory device at high speed at other times.
摘要:
A semiconductor memory device includes a memory cell array, a spare memory cell array, a first addressing circuit for designating an address of the memory cell array, a second addressing circuit for designating an address of the spare memory cell array, a drive circuit for activating a select line designated by each of the first and second addressing circuits, a program circuit for generating a predetermined output based on whether the memory cell array has a defect or fault or not, and a select circuit responsive to an output from the program circuit for supplying an activation signal to the designated select line at an earlier timing when there is no fault in the memory array cell, and supplying an activation signal delayed by a time necessary for the selection of the spare memory cell array when there is a fault in the memory cell array.
摘要:
Two or more voltage bootstrap circuits are included, and are sequentially operated. A continuous data write/read operation can be performed at a high speed. One of the two voltage bootstrap circuits is used for the data write/read operation and the other thereof is used for the refresh operation, thereby shortening the time required for refreshing.