Abstract: A fast DRAM memory uses ground-sensing as opposed to traditional Vdd/2 sensing. A selected DRAM cell connects to a bit-line true (BLT) or a bit-line complement (BLC). At the start of each cycle the BLT and BLC are restored to ground potential. A pair of alternating reference cells are provided for each bit-line. When a selected DRAM cell is connected either BLT or BLC the first reference cell in the pair is connected to the other bitline to provide a reference voltage to the other bitline which can be compared to the voltage provided by the selected DRAM cell. On a subsequent cycle using the same bitline the second reference cell in the pair is used. Thus it is not necessary to wait for the first reference cell to recharge prior to beginning the next cycle. Switching between the first and second reference cells in the pair alternates in this manner resulting in faster cycle time.

Abstract: A method and structure for a content addressable memory (CAM) array having a plurality of memory cells. Each of the memory cells has capacitive storage devices, transistors connected to the storage devices, a wordline connected to and controlling the transistors, bitlines connected to the storage devices through the transistors, combined search and global bitlines connected to the capacitive storage devices. These cells are further arranged into columns, each containing multiplexers connected to the combined search and global bitlines, data-in lines connected to the multiplexers, and search-data lines connected to the multiplexers. Further, the multiplexers select between the data-in lines and the search-data lines to allow the combined search and global bitlines to be alternatively used as data lines and search lines. Also, in the invention each of the columns further has drivers between the multiplexers and the combined search and global bitlines.

Abstract: A system and method is disclosed for operating a content addressable memory (CAM) within an integrated circuit using search signals at search input voltages which are substantially independent from an operating voltage of the CAM. A method is disclosed in which search signals are input to CAM cells of the CAM at search input voltages which are substantially independent of an operating voltage of storage elements within the CAM cells. A match signal is output upon detecting a matching condition between the search signals and data stored in the storage elements. The search input voltage can be within about 0.2V above a threshold voltage of a search input device of the CAM memory cell. Search input devices can be selected to have a lower threshold voltage than other devices included within the CAM cell.

Abstract: A Dynamic Content Addressable Memory (DCAM) cell topology that contains fewer that can perform a “hidden” refresh of stored data that does not delay nor interrupt the CAM search cycle, thereby providing SCAM-like performance. A non-destructive read operation, is performed such that the stored-data does not have to be written back because of a refresh-read operation. A reliable CAM search can be performed after a read operation and before or even while the refresh-data is being written back. Soft-error detection processes can be performed on each CAM entry during the pendency of the refresh cycle. The DCAM cell can be used in a digital system such as a digital computer and a Network Router.

Abstract: A Dynamic Content Addressable Memory (DCAM) cell topology that contains fewer that can perform a “hidden” refresh of stored data that does not delay nor interrupt the CAM search cycle, thereby providing SCAM-like performance. A non-destructive read operation, is performed such that the stored-data does not have to be written back because of a refresh-read operation. A reliable CAM search can be performed after a read operation and before or even while the refresh-data is being written back. Soft-error detection processes can be performed on each CAM entry during the pendency of the refresh cycle. The DCAM cell can be used in a digital system such as a digital computer and a Network Router.

Abstract: A semiconductor memory device having resistive bitline contact testing includes memory cells, and wordline logic devices for concurrently activating two adjacent memory cells. The two adjacent memory cells are activated concurrently to allow higher current through a bitline contact for improved detection of resistive bitline contacts. A test cell may also be included to test the integrity of the bitline contact.

Abstract: Scannable fuse latches are provided that can override current fuse values, read current fuse values, and latch current fuse values. Using the scannable fuse latches of the current invention allows current fuse values to be overridden, which can be important in testing and failure analysis to place the integrated circuit in a known state. The scannable fuse latches of the current invention also allow current fuse values to be read. This aids failure analysis because the current state of the failed integrated circuit can be determined. Finally, the scannable fuse latches of the present invention allow the current state of fuses to be latched and provided to a core of an integrated circuit.

Abstract: A dynamic bus system with a central precharge device is disclosed that utilizes a controller circuit with a one-shot generator and write synchronizing circuits in combination with logic output modules having pull-up/down devices. The issuance of the output enable (OE) signals is interlocked with the turn-off of the precharge. Thus, data is written to the dynamic bus only when the precharge device is inactive, avoiding bus collisions. The resulting circuitry not only ensures the precharging of the bus before the data write to the bus, but will allow the synchronized OE signals to be issued during the same clock phase as the precharge signal.

Abstract: In one aspect a memory bank selection system includes two asynchronous RAS pins and a single CAS pin, a switching circuit for each memory bank and a bank address decoder with an output to each switching circuit. The RAS pins are available to all of the switching circuits. A given switching circuit selects its associated bank if an active RAS signal is present and the bank address decoder output was sent thereto. The number of memory banks that can be simultaneously active directly depends on the number of RAS inputs. In another aspect, the number of CAS pins is equal to the number of asynchronous RAS pins.

Abstract: A memory chip, comprising a chip memory section organized to hold a plurality of separate blocks of data, with each of the data blocks containing M individual data units; a circuit for addressing a given block of data in the chip memory section; and an N data unit chip parallel output interface from the memory chip where N is less than M, and N is greater than one. The memory chip further comprises a chip register for receiving from the chip memory section at least a portion of an addressed block of data, which portion comprises P data units, where P is greater than N, the chip register having P register stages for holding the P data units of the addressed data block, wherein the P register stages are grouped into at least a first and second groups of stages, with no group of stages comprising more than N register stages and with at least one of the groups of register stages having a plurality of stages.

Abstract: A method and device for setting at least three operating modes of a memory device is provided. The voltage signal is sensed at a first input and an enable signal is sensed at a second input. When an enable signal is received at a second input the memory device operates at the first operating mode if the voltage state at the first input is low; it operates at a second mode if the voltage state at the second is high; and it operates at a third operating mode if the voltage at the first input changes after the enable signal is received at the input. Also a four mode operation can be achieved.

Abstract: A memory device which includes several partially defective memory chips and a control circuit for receiving an address signal corresponding to a storage cell address of each of the partially defective memory chips, and for controlling, in response to the address signal, the partially defective memory chips such that only one thereof is enabled.

Abstract: A dual sense amplifier construction with divided bit line isolation. A switch is disposed at approximately the midpoint of a bit line to divide the bit line into first and second bit line segments. When opened, the switch provides electrical isolation between the first and second bit line segments so that an accessed memory charge can be isolated from one-half of the capacitance associated with the bit line. Once the isolated memory charge is read and pre-amplified, the remaining bit line capacitance is no longer of concern. The switch is then closed to provide electrical connection between the first and second bit line segments, thereby allowing the completion of the amplification operation.