摘要:
A dynamic logic circuit having a charging circuit, comprising a first transistor having a first source/drain electrode adapted for coupling to a voltage supply and a second source/drain electrode connected to a node. The charging circuit couples the voltage supply to the node to place an initial charge on the node. A data transfer circuit is provided comprising a second transistor having a gate adapted for coupling to an input strobe pulse, a first source/drain electrode connected to the node, and a second source/drain electrode responsive to an input data and the input strobe pulse, for transferring the input data to the node to the node such that the pre-charged node is either discharged or remains depending on the input data. An output circuit is responsive to an output strobe pulse for coupling the data at the node to an output. A trailing edge detector of the output strobe pulse detects a time at which the coupling of the data to the output is complete and pre-charges the node at a high level for a subsequent input strobe pulse.
摘要:
A method of self-programmable Built In Self Test (BIST) for a memory (e.g., Dynamic Random Access Memory (DRAM)). The DRAM, which may be a DRAM chip, includes a DRAM core, a Microcode or Initial Command ROM, a BIST Engine, a Command Register and a Self-Program Circuit. During self test, the BIST engine may test the DRAM normally until an error is encountered. When an error is encountered, the Self-Program Circuit restarts the self test procedure at less stringent conditions. Optionally, when the DRAM tests error-free, the Self-Program Circuit may restart testing at more stringent conditions to determine DRAM functionality limits.
摘要:
An integrated circuit (IC) chip wherein a built-in self test determines the IC's optimum electrical performance. A corresponding optimum performance setting is stored in NVRAM on the chip. Upon each chip power-up, the optimum performance setting is retrieved and provided to chip control which sets the chip for its best performance.
摘要:
A defect management engine (DME) for memories integrates a plurality of redundancy data cells and a plurality of redundancy address cells in the same array. The redundancy data cells are used for replacing defective cells in the memories. The redundancy address cells store the addresses of the defective cells. The memories are preferably sub-divided into a plurality of domains. A plurality of defective cells in each domain are supported by a plurality of repair units, each consisting of one or more redundancy data bits and redundancy address bits in the DME. When one or more data bits are read from a domain in the memory, the corresponding wordline in the DME simultaneously activates a plurality of repair units coupling to the wordline (self-contained domain selection). The redundancy data bits and the redundancy address bits are also read from the redundancy data cells and redundancy address cells, respectively. The DME logic detects whether or not the redundancy address bits match or do not match the address inputs of each repair unit (self contained redundancy match detection). This couples either redundancy data bits from the DME (i.e., a matching condition) or the data bits from the domain in the memories (i.e., a no match condition) to the corresponding DQ (self-contained redundancy replacement). The DME enables an integrated redundancy means (self-contained domain selection, self-contained redundancy match detection, and self-contained redundancy replacement). Single bit replacement, multi-bit replacement, line replacement, and variable bit size replacement are discussed. Finally, an extension of the DME concept to a memory system is also discussed.
摘要:
A wordline activation delay monitor circuit is disclosed herein which includes a sample wordline located within a data-storing array of a memory, wherein the sample wordline is selected or activated by circuitry having substantially the same structure or location within the memory as circuitry which selects or activates wordlines of the data-storing array. A circuit is disclosed which determines a wordline activation delay for a first subarray group within the memory by activating a sample wordline which is located within a data-storing array of a second subarray group. Corresponding methods are also disclosed.
摘要:
A system is disclosed herein for stabilizing the current dissipation, voltage drop, and heating effects related to accessing blocks within first and second storage units of a double memory unit. The system includes a row selection unit located between the first and second storage units, which accesses storage locations of the first and second storage units according to first and second selection signals conducted from the outer extremities of the double memory unit to selected row locations. The blocks at corresponding distances from the outer extremities are numbered differently such that the sum of lengths of signal travel of the first and second selection signals to the numbered blocks remains relatively constant regardless of the block number which is selected for access.
摘要:
A fault-tolerant memory device provided with a variable domain redundancy replacement (VDRR) arrangement is described. The memory device includes: a plurality of primary memory arrays; a plurality of domains having at least portions of one domain common to another domain to form an overlapped domain area, and at least one of the domains overlapping portions of at least two of the primary memory arrays; redundancy units, coupled to each of the domains, for replacing faults contained within each of the domains; control circuitry for directing at least one of the faults within one of the domains to be replaced with the redundancy units, wherein at least one other fault of the one domain is replaced by the redundancy unit coupled to another of the domains, if the at least one other fault is positioned within the overlapped domain area. Each redundancy unit supporting the primary memory arrays includes a plurality of redundant elements. Unlike the conventional fixed domain redundancy replacement scheme, RUs are assigned to at least two variable domains, wherein at least a portion of the domain is common to that of another domain. The VDRR makes it possible to choose the most effective domain, and in particular, a smaller domain for repairing a random fault or a larger domain for repairing a clustered faults.
摘要:
A method and apparatus for repairing a semiconductor memory device. A row redundancy replacement arrangement is provided to repair the memory device consisting of a first plurality of redundant true word lines and a second plurality of redundant complement word lines to simultaneously replace the same first number of first normal word lines and the same second number of the normal complement word lines. An address reordering scheme, preferably implemented as a word line selector circuit and controlled by redundancy control logic and address inputs, allows the redundant true (complement) word lines to replace the normal true (complement) word lines when making the repair. The redundancy replacement arrangement ensures that consistency of the bit map is maintained at all times, irrespective whether the memory device operates in a normal or in a redundancy mode. This approach introduces an added flexibility of incorporating the redundancy replacement without affecting the column access speed.
摘要:
A method of making a memory fault-tolerant through the use of a variable size redundancy replacement (VSRR) circuit arrangement. A redundancy array supporting the primary arrays forming the memory includes a plurality of variable size redundancy units, each of which encompassing a plurality of redundant elements. The redundant units used for repairing faults in the memory are independently controlled. All the redundancy elements within a repair unit are preferably replaced simultaneously. The redundancy elements in the redundancy unit are controlled by decoding address lines. The variable size that characterizes this configuration makes it possible to choose the most effective redundancy unit, and in particular, the one most closely fitting the size of the cluster of failures to be replaced. This method significantly reduces the overhead created by added redundancy elements and control circuitry, while improving the access speed and reducing power consumption. Finally, a fault-tolerant block redundancy controlled by a priority decoder makes it possible to use VSRR units for repairing faults in the block redundancy prior to its use for replacing a defective block within the memory.
摘要:
An address decode circuit for receiving address input signals, includes a device for detecting a change in the address input signals, and a device for generating a control signal in response to a detected change in the address input signals. A gating mechanism gates at least one address bit in the address input signals input to the address decode circuit with the control signal.