Abstract: A sensing circuit for performing a direct read of a DRAM memory cell by using a high transfer ratio and a single ended read of a single bitline, wherein a limited number of memory cells are connected to the single bitline to limit the capacitance thereof to provide the high transfer ration. The direct read circuit includes four transistor devices, with three devices preferentially being nFETs. The direct read circuit provides a self-timed write back of data to a memory cell after the data is destructively read from the memory cell in a read operation, provides significant electrical power savings relative to prior art read circuits, as a read operation of a data 0 does not utilize any significant electrical power, and in a folded bitline architecture provides improved noise immunity as each non-active bitline shields an adjacent active bitline.

Abstract: A growable multibank DRAM macro is achieved with a flexible multibank interface which can be grown without redesign and without change of appearance/behavior to the customer. The interface is preferably characterized by the presence of bank select inputs (pins) which permit selection of one or more banks of the macro. The banks preferably each have respective row decode circuitry and respective limited repair redundancy.

Abstract: A method and circuit for a self timed DRAM. The circuit includes interlock circuits coupled to an extension of the DRAM. The extension does not store “real” data but mimics the operations of the DRAM. The interlock circuits, in conjunction with the extension monitor and control read and write timings of the DRAM and self adjust these timings via feedback. To properly track DRAM cell timings, the interlock circuits and extension use the same cell design and load conditions as the DRAM. The method includes: activating a wordline and reference wordline, interlocking the sense amplifiers, column select and write back functions of the primary DRAM array by monitoring the identical reference cells and the state of the bitline in the extension DRAM array.

Abstract: An ECC based system and method within an integrated circuit memory for self-repair of a failed memory element is disclosed. The method includes processing, within the integrated circuit, data and check bits retrieved from addressed memory locations therein. The locations of memory failures are automatically recorded within the integrated circuit. Logic circuits within the integrated circuit automatically identify failure patterns based on the locations. Based on the identified failure patterns, logic circuits within the integrated circuit then permanently replace a failed memory element with an appropriate redundancy element, using devices such as electronic fuse or antifuse. In this manner, the integrated circuit automatically identifies and effects self repair of a failed memory element therein.

Abstract: A column redundancy system is disclosed for a memory array having a page structure organized into columns and data lines. In an exemplary embodiment of the invention, the system includes a steering logic network for coupling a memory input/output (I/O) device to the memory array. A storage register is in communication with the steering logic network, the storage register for storing location information for defective data lines in the memory array. During a memory operation, the location information stored in the storage register is transmitted to the steering logic network, the storage register further having the location information loaded therein prior to the memory operation. Thereby, the steering logic network prevents any of the defective data lines from being coupled to the I/O device.

Abstract: A column redundancy system is disclosed for a memory array having a page structure organized into columns and data lines. In an exemplary embodiment of the invention, the system includes a steering logic network for coupling a memory input/output (I/O) device to the memory array. A storage register is in communication with the steering logic network, the storage register for storing location information for defective data lines in the memory array. During a memory operation, the location information stored in the storage register is transmitted to the steering logic network, the storage register further having the location information loaded therein prior to the memory operation. Thereby, the steering logic network prevents any of the defective data lines from being coupled to the I/O device.

Abstract: A method of memory BIST (Built-In Self Test) and memory repair that stores a redundancy calculation on-chip, as opposed to scanning this data off-chip for later use. This method no longer requires level-sensitive scan design (LSSD) scanning of memory redundancy data off-chip to the tester, and therefore does not require re-contacting of the chip for electrical fuse blow.

Abstract: Addition of capacitance to the storage nodes of static random access memory cells and other types of integrated circuits substantially increases Qcrit and substantially eliminates soft errors due to alpha particles; susceptibility to which would otherwise increase as integrated circuits are scaled to smaller sizes and manufactured at increased integration densities. Formation of the added capacitance as deep trench capacitors avoids any constraint on circuit or memory cell layout. Degradation of performance is avoided and performance potentially improved by permitting alteration of proportions of pull-down and pass gate transistors in view of the increased stability imparted by the added capacitors. One of the capacitor electrodes is preferably shorted to the supply voltage through an impurity well. Thus, the memory cell size can be reduced while greatly reducing susceptibility to soft errors; contrary to the effects of scaling at current and foreseeable feature size regimes.

Abstract: A system and method is disclosed for writing early within a memory cycle by injecting a small voltage difference signal prior to setting a sense amplifier, and thereafter setting the sense amplifier which amplifies the small voltage signal to predetermined high and low voltage logic levels for writing to the memory cell. In this way, writing can complete in about the same time as reading, without risking corruption of data on adjacent bitlines in the memory. Local bitswitches apply first and second write voltages having a small voltage difference to a true bitline and a reference bitline prior to setting the sense amplifier.

Abstract: A system and method is disclosed for writing early within a memory cycle by injecting a small voltage difference signal prior to setting a sense amplifier, and thereafter setting the sense amplifier which amplifies the small voltage signal to predetermined high and low voltage logic levels for writing to the memory cell. In this way, writing can complete in about the same time as reading, without risking corruption of data on adjacent bitlines in the memory. Local bitswitches apply first and second write voltages having a small voltage difference to a true bitline and a reference bitline prior to setting the sense amplifier. Local bitswitches on such other memory cells not currently being written are adapted to isolate true and reference bitlines coupled to those memory cells prior to the setting of sense amplifiers coupled to those bitlines, such that the stored contents of such memory cells not being written are refreshed at the time that the selected memory cell is written.

Abstract: Wafer test and burn-in is accomplished with state machine or programmable test engines located on the wafer being tested. Each test engine requires less than 10 connections and each test engine can be connected to a plurality of chips, such as a row or a column of chips on the wafer. Thus, the number of pads of the wafer that must be connected for test is substantially reduced while a large degree of parallel testing is still provided. The test engines also permit on-wafer allocation of redundancy in parallel so that failing chips can be repaired after burn-in is complete. In addition, the programmable test engines can have their code altered so test programs can be modified to account for new information after the wafer has been fabricated. The test engines are used during burn-in to provide high frequency write signals to DRAM arrays that provide a higher effective voltage to the arrays, lowering the time required for burn-in.

Abstract: A system and method is disclosed for writing early within a memory cycle by holding only one of a true bitline and a reference bitline at a fixed potential, e.g. ground, when the sense amplifier is set. The sense amplifier amplifies a small voltage difference between the true bitline and the reference bitline to predetermined high and low voltage logic levels to write a datum to the memory cell. In this way, writing can complete in about the same time as reading, without risking corruption of data on adjacent bitlines in the memory. The bitlines are precharged to a fixed potential in a conduction path through the bitswitches, rather than using local precharge devices at the sense amplifier. To write, bitswitches and write path transistors apply the fixed potential to one of the true bitline and the reference bitline.

Abstract: Wafer test and burn-in is accomplished with state machine or programmable test engines located on the wafer being tested. Each test engine requires less than 10 connections and each test engine can be connected to a plurality of chips, such as a row or a column of chips on the wafer. Thus, the number of pads of the wafer that must be connected for test is substantially reduced while a large degree of parallel testing is still provided. The test engines also permit on-wafer allocation of redundancy in parallel so that failing chips can be repaired after burn-in is complete. In addition, the programmable test engines can have their code altered so test programs can be modified to account for new information after the wafer has been fabricated. The test engines are used during burn-in to provide high frequency write signals to DRAM arrays that provide a higher effective voltage to the arrays, lowering the time required for burn-in.

Abstract: A twin cell memory array which includes shielded bitlines is provided. The twin cell memory array includes a plurality of bitlines arranged in one direction in parallel with each other, with every other bitline constituting a bitline pair; a plurality of sense amplifiers being arranged in a line, wherein each sense amplifier is interconnected to two adjacent bitline pairs; a plurality of wordlines arranged in a direction intersecting said plurality of bitlines, wherein a single wordline is coupled to every other bitline; and isolation means located on said plurality of bitlines, said isolation means being arranged such that when every other bitline of said plurality of bitlines is being sensed, the adjacent bitlines of said plurality of bitlines are held at a predetermined potential by a clamping means.

Abstract: Wafer test and burn-in is accomplished with state machine or programmable test engines located on the wafer being tested. Each test engine requires less than 10 connections and each test engine can be connected to a plurality of chips, such as a row or a column of chips on the wafer. Thus, the number of pads of the wafer that must be connected for test is substantially reduced while a large degree of parallel testing is still provided. The test engines also permit on-wafer allocation of redundancy in parallel so that failing chips can be repaired after burn-in is complete. In addition, the programmable test engines can have their code altered so test programs can be modified to account for new information after the wafer has been fabricated. The test engines are used during burn-in to provide high frequency write signals to DRAM arrays that provide a higher effective voltage to the arrays, lowering the time required for burn-in.

Abstract: An embedded memory macro device includes a memory system and a logic circuit constructed on a common semiconductor substrate. The memory system and logic circuit communicate through a handshake procedure via a system data interlock signal. During read cycles the memory system uses the system data interlock signal to tell the logic circuit when data at memory system data outputs is valid. In the preferred embodiment, during write cycles the memory system uses the system data interlock signal to tell the logic circuit when data has been successfully written. The logic circuit needs to wait only until the system data interlock signal permits it to proceed. It then signals the memory system to reset the system data interlock signal and can immediately initiate a new read or write cycle.

Abstract: A method is provided for flash writing to multiple cells of a memory array. Initially, a first set of word lines, each of which controls connection of a memory cell of a first set of memory cells to a first bit line of a bit line pair, is turned on. The voltage between the two bit lines of the bit line pair is then equalized so that the charge on the first bit line of the bit line pair is higher than the charge on the second bit line of the bit line pair. Next, a sense amplifier attached to the bit line pair is turned on to sense a difference in charge between the bit line pair and to charge the first set of memory cells. Then a second set of word lines, each of which controls connection of a memory cell of a second set of memory cells to the second bit line is turned on. Finally, the word lines previously turned on are shut off and then the sense amplifier is shut off.

Abstract: A DRAM having on-chip ECC and both bit and word redundancy that have been optimized to support the on-chip ECC. The bit line redundancy features a switching network that provides an any-for-any substitution for the bit lines in the associated memory array. The word line redundancy is provided in a separate array section, and has been optimized to maximize signal while reducing soft errors. The array stores data in the form of error correction words (ECWs) on each word line. A first set of data lines (formed in a zig-zag pattern to minimize unequal capacitive loading on the underlying bit lines) are coupled to read out an ECW as well as the redundant bit lines. A second set of data lines receive the ECW as corrected by bit line redundancy, and a third set of data lines receive the ECW as corrected by the word line redundancy. The third set of data lines are coupled to the ECC block, which corrects errors encountered in the ECW.

Abstract: Low power addressing systems are provided which include a given number of memory segments, each having word and bit/sense lines, a given number of decoders coupled to the given number of memory segments for selecting one word line in each of the memory segments, a first plurality of transmission gate systems, each having first and second transmission gates, with each of the gates being coupled to a different one of the decoders, a second decoder having the first plurality of outputs, each of the outputs being coupled to a respective one of the transmission gate systems, first control circuits for selectively activating the first and second gates in each of the first plurality of transmission gate systems, a second given number of decoders coupled to the given number of memory segments for selecting one bit/sense line in each of the memory segments, a second plurality of transmission gate systems, each having first and second transmission gates, with each of the gates of the second plurality of transmission ga