Abstract: A memory circuit includes multiple word lines, multiple pairs of complementary bank bit lines, multiple block select lines, and multiple of block circuits. Each of the block circuits includes a local bit line; a first transistor having a control terminal connected to the local bit line, a first bias terminal connected to a first bank bit line of a given pair of bank bit lines, and a second bias terminal connecting to a first voltage source; a second transistor having a control terminal connected to a corresponding one of the block select lines, a first bias terminal connected to a second bank bit line of the given pair of bank bit lines, and a second bias terminal connected to the local bit line; and a plurality of memory cells connected to the local bit line and to respective word lines in the memory circuit.

Abstract: A sense amplifier circuit for sensing a logic state of a selected memory cell in a memory circuit includes a precharge circuit and a latch circuit. The precharge circuit is adapted for connection to a pair of complementary bit lines corresponding to the selected memory cell and is operative to selectively drive the pair of complementary bit lines to a first voltage in response to a first control signal. The latch circuit is adapted for connection to the pair of complementary bit lines. The sense amplifier circuit further includes a replication circuit adapted for connection to the pair of complementary bit lines. The replication circuit is operative to selectively transfer a voltage representative of a logic state on a first bit line of the pair of complementary bit lines to a second bit line of the pair of complementary bit lines in response to at least a second control signal.

Abstract: A sense amplifier circuit for sensing a logic state of a selected memory cell in a memory circuit includes a precharge circuit and a latch circuit. The precharge circuit is adapted for connection to a pair of complementary bit lines corresponding to the selected memory cell and is operative to selectively drive the pair of complementary bit lines to a first voltage in response to a first control signal. The latch circuit is adapted for connection to the pair of complementary bit lines. The sense amplifier circuit further includes a replication circuit adapted for connection to the pair of complementary bit lines. The replication circuit is operative to selectively transfer a voltage representative of a logic state on a first bit line of the pair of complementary bit lines to a second bit line of the pair of complementary bit lines in response to at least a second control signal.

Abstract: A memory circuit includes multiple word lines, multiple pairs of complementary bank bit lines, multiple block select lines, and multiple of block circuits. Each of the block circuits includes a local bit line; a first transistor having a control terminal connected to the local bit line, a first bias terminal connected to a first bank bit line of a given pair of bank bit lines, and a second bias terminal connecting to a first voltage source; a second transistor having a control terminal connected to a corresponding one of the block select lines, a first bias terminal connected to a second bank bit line of the given pair of bank bit lines, and a second bias terminal connected to the local bit line; and a plurality of memory cells connected to the local bit line and to respective word lines in the memory circuit.

Abstract: Apparatus for passively tracking expired data in a dynamic memory includes an error encoding circuit operative to receive an input data word and to generate an encoded data word which is stored in the dynamic memory. The apparatus further includes a decoding circuit operative to receive an encoded data word from the dynamic memory, to detect at least one or more unidirectional errors in the input data word read from the dynamic memory, and to generate an error signal when at least one error is detected, the error signal indicating that the input data word contains expired data. Control circuitry included in the apparatus is configured for initiating one or more actions in response to the error signal.

Abstract: A method for replacing cache lines in a computer system having a non-uniform set associative cache memory is disclosed. The method incorporates access latency as an additional factor into the existing ranking guidelines for replacement of a line, the higher the rank of the line the sooner that it is likely to be evicted from the cache. Among a group of highest ranking cache lines in a cache set, the cache line chosen to be replaced is one that provides the lowest latency access to a requesting entity, such as a processor. The distance separating the requesting entity from the memory partition where the cache line is stored most affects access latency.

Abstract: A system and method for accessing a data cache having at least two ways for storing data at the same addresses. A first and second tag memory store first and second sets of tags identifying data stored in each of the ways. A translation device determines from a system address a tag identifying one of the ways. A first comparator compares tags in the address with a tag stored in the first tag memory. A second comparator compares a tag in the address with a tag stored in the second tag memory. A clock signal supplies clock signals to one or both of the ways in response to an access mode signal. The system can be operated so that either both ways of the associative data cache are clocked, in a high speed access mode, or it can apply clock signals to only one of the ways selected by an output from the first and second comparators in a power efficient mode of operation.

Abstract: A system and method for reducing latency in memory systems is provided. A copy way is established in a set of a set associative cache, which is physically closer to a requesting entity than other memory positions. Likely to be accessed data is copied to the copy way for subsequent access. In this way, subsequent accesses of the most likely data have their access time reduced due to the physical proximity of the data being close to the requesting entity. Methods herein further provide ranking and rearranging blocks in the cache based on coupled local and global least recently used (LRU) algorithms to reduce latency time.

Abstract: A magnetic random access memory circuit comprises a plurality of magnetic memory cells, each of the memory cells including a magnetic storage element having an easy axis and a hard axis associated therewith, and a plurality of column lines and row lines for selectively accessing one or more of the memory cells, each of the memory cells being proximate to an intersection of one of the column lines and one of the row lines. Each of the magnetic memory cells is arranged such that the easy axis is substantially parallel to a direction of flow of a sense current and the hard axis is substantially parallel to a direction of flow of a write current.

Abstract: A random access memory circuit comprises a plurality of memory cells and at least one decoder coupled to the memory cells, the decoder being configurable for receiving an input address and for accessing one or more of the memory cells in response thereto. The random access memory circuit further comprises a plurality of sense amplifiers operatively coupled to the memory cells, the sense amplifiers being configurable for determining a logical state of one or more of the memory cells. A controller coupled to at least a portion of the sense amplifiers is configurable for selectively operating in at least one of a first mode and a second mode. In the first mode of operation, the controller enables one of the sense amplifiers corresponding to the input address and disables the sense amplifiers not corresponding to the input address. In the second mode of operation, the controller enables substantially all of the sense amplifiers.

Abstract: A number of performance parameters for the electronic system are determined at a particular age of the electronic system. The performance parameters can be correlated to maximum operating frequency of electronic components of the electronic system for the particular age of the electronic system. Operating frequency of the electronic components is adjusted in accordance with the performance parameters. The performance parameters may be predetermined (such as through reliability and burn-in testing), determined during the life of the electronic system, or some combination of these. Performance parameters can comprise prior operating frequencies, hours of operation, ambient temperature, and supply voltage. Performance parameters can comprise performance statistics determined using age-monitoring circuits, where an aged circuit is compared with a circuit enabled only for comparison. Performance statistics may also be determined though error detection circuits.