Agere Systems Inc.

Lsi Corporation

Lucent Technologies Inc.

At&t Bell Laboratories

American Telephone & Telegraph Co., At&t Bell Laboratories

Ronald James Wozniak

Donald Albert Evans

Wayne E Werner

Hai Quang Pham

Dennis E Dudeck

Richard Joseph McPartland

Ankur Goel

Richard John Stephani

Dharmendra Kumar Rai

Rasoju Veerabadra Chary

Ronald N Graver

Kurt M Striny

Jeffrey Charles Herbert

Kenneth K Claasen

Frank P Pelletier

A memory device comprises a memory block, a power gating transistor, and control circuitry. The memory block includes at least one memory cell comprising a storage element electrically connected to a source potential line, a drive strength of the storage element being a function of a voltage level on the source potential line. The power gating transistor, in turn, is connected between the source potential line and a voltage source. The control circuitry is operative to configure the power gating transistor to electrically connect the source potential line to the voltage source while the memory block is in a first mode, and to clamp the source potential line at a voltage different from that of the voltage source when the memory block is in a second mode.

Memory device with area efficient power gating circuitry

A memory device comprises a memory array and error correction circuitry coupled to the memory array. The error correction circuitry is configured to identify, in a data word retrieved from the memory array, at least one bit position corresponding to a predetermined defect location in the memory array, and to generate a corrected data word by automatically inverting a logic value at the identified bit position. This automatic logic inversion approach is particularly well suited for use in correcting output data errors associated with via defects and weak bit defects in high-density ROM devices.

Memory device with error correction based on automatic logic inversion

A memory device comprises a memory array and a phase distribution circuit coupled to the memory array. In one aspect, the phase distribution circuit is operative to control respective durations of a precharge phase and an active phase of a memory cycle of the memory array based on relative transistor characteristics of a tracked precharge transistor of a first conductivity type and a tracked memory cell transistor of a second conductivity type different than the first conductivity type. For example, the phase distribution circuit may comprise a first tracking transistor of the first conductivity type for tracking the precharge transistor of the first conductivity type and a second tracking transistor of the second conductivity type for tracking the memory cell transistor of the second conductivity type. The relative transistor characteristics may comprise relative strengths of the tracked precharge and memory cell transistors.

Memory device with phase distribution circuit for controlling relative durations of precharge and active phases

A memory circuit includes a plurality of memory cells and a plurality of bit lines and row lines connected to the memory cells for accessing selected memory cells. The memory circuit includes a programmable voltage source adapted for connection to at least one bit line and operative to precharge the bit line to a prescribed voltage level prior to accessing a selected one of the memory cells coupled to the bit line. A control circuit coupled to the bit line is operative to oppose discharge of the bit line during at least a portion of a given memory read cycle. A tracking circuit connected to the control circuit is operative to control a delay in activation of the control circuit and/or a duration of time the control circuit is active as a function of a parameter affecting signal development time of a data signal on the bit line.

Tracking circuit for reducing faults in a memory

A nonvolatile memory comprising an array of memory cells and sense amplifiers, each sense amplifier using a keeper circuit to provide an amount of current to compensate for bit line leakage current in the memory array. The amount of current from the keeper depends on the temperature of the memory and the speed of the process used to make the memory.

Process and temperature tolerant non-volatile memory

A memory device comprises a memory array, at least one buffer coupled to the memory array, and test circuitry coupled to the buffer. The buffer comprises switching circuitry configured to multiplex first and second inputs of the buffer to a given output of the buffer based at least in part on a control signal generated by the test circuitry. The control signal is generated as a function of both a test signal indicative of a test mode of operation of the memory device and a power-down signal indicative of a power-down mode of operation of the memory device. The buffer further comprises current reduction circuitry responsive to the control signal for reducing an amount of current consumed by the buffer in the power-down mode of operation. The buffer may comprise an input data buffer or an address buffer of the memory device.

Memory device with reduced buffer current during power-down mode

A sense amplifier includes a first sensing element and a second sensing element redundant to the first sensing element. The sense amplifier further comprises a switch circuit configured to switch between the first and second sensing elements when an offset of the sense amplifier is greater than a prescribed amount.

Sense amplifier with redundancy

A memory circuit having reduced power consumption includes a plurality of memory sub-arrays and a shared circuit coupled to each of the memory sub-arrays. Each memory sub-array includes at least one row circuit, at least one column circuit, and a plurality of memory cells operatively coupled to the row and column circuits. The row and column circuits are operative to provide selective access to one or more of the memory cells. The shared circuit includes circuitry, external to the memory sub-arrays, which is operative to control one or more functions of the memory sub-arrays as a function of at least one control signal supplied to the memory circuit. The memory circuit is operative, with at least one of the memory sub-arrays operative, with one or more of the memory sub-arrays powered and concurrently with one or more of the memory sub-arrays unpowered.

Memory circuit having reduced power consumption

A word line driver circuit for use in a memory array including multiple memory cells and multiple word lines coupled to the memory cells for selectively accessing the memory cells includes a driver adapted to generate a word line signal as a function of a first set of address signals received by the word line driver circuit. The circuit further includes a switching circuit having a plurality of output nodes, the output nodes connected to respective ones of the plurality of word lines, and having an input node connected to an output of the driver and adapted to receive the word line signal. The switching circuit is operative to direct the word line signal to a selected one of the word lines during a memory access as a function of at least one control signal. Between a given pair of memory accesses, the output nodes and the input node of the switching circuit are held to a same prescribed voltage level to thereby substantially eliminate a leakage current path in the switching circuit.

Word line driver circuit with reduced leakage

A row line driver circuit for use in a memory array including multiple memory cells and multiple row lines coupled to the memory cells for selectively accessing the memory cells includes an output stage adapted for connection to a corresponding one of the row lines and a control circuit connected to the output stage. The output stage is operative during an active phase of a given memory cycle to drive the corresponding row line to a potential as a function of at least one address signal received by the driver circuit. The control circuit is operative to generate at least one control signal for disabling the output stage at least during an inactive phase of the memory cycle to thereby substantially eliminate a leakage current path in the driver circuit.

Reduced leakage driver circuit and memory device employing same

A memory cell for use in a content-addressable memory comprises a first latch and a second latch. The first latch is operative to store a first bit associated with a first stored word, while the second latch is operative to store a second bit associated with a second stored word. The first and second latches collectively comprise a plurality of latch transistors. Each of the latch transistors comprises a respective channel. The channels of the latch transistors are oriented in substantially the same direction, resulting in a very compact memory cell implementation.

Memory cell for content-addressable memory

A single-ended sensing circuit is provided for use with a memory circuit including a plurality of bit lines and a plurality of memory cells connected to the bit lines. The sensing circuit includes at least one charge sharing circuit and at least one switching circuit connected to the charge sharing circuit. The switching circuit is operative to selectively connect the charge sharing circuit to at least a given one of the bit lines as a function of a first control signal supplied to the switching circuit. The sensing circuit further includes at least one comparator circuit connected to the given bit line. The comparator circuit is operative to generate an output signal indicative of a logical state of a memory cell connected to the given bit line. The charge sharing circuit is operative to remove an amount of charge on the given bit line so as to reduce a voltage on the given bit line in conjunction with a read access of the memory cell.

Accelerated single-ended sensing for a memory circuit

A sensing circuit for use with a CAM circuit including multiple match lines and multiple CAM cells connected to the match lines includes at least one charge sharing circuit and at least one switching circuit connected to the charge sharing circuit. The switching circuit is operative to selectively connect the charge sharing circuit to a corresponding one of the match lines as a function of a first control signal supplied to the switching circuit. The sensing circuit further includes at least one comparator circuit connected to the corresponding match line and operative to generate an output signal indicative of a match between search data supplied to at least a given one of the CAM cells connected to the corresponding match line and data stored in the given CAM cell. The charge sharing circuit is operative to remove an amount of charge on the corresponding match line so as to reduce a voltage on the corresponding match line in conjunction with a search operation of the CAM cell.

Accelerated searching for content-addressable memory

An integrated circuit includes memory circuitry with a number of bit line structures, each including at least three bit lines; a number of word lines that intersect with the bit line structures at a number of sites; and a number of switching devices located at the sites. A number of Vplanes are interconnected with the switching devices. The switching devices and the Vplanes are formed at a first level. The Vplanes can be formed as substantially complementary interlocking regions that also form functional portions of the switching devices. The switching devices can be connected between an adjacent one of the word lines and a selected one of the bit lines of an adjacent one of the bit line structures for selective electrical conduction therebetween upon activation by the adjacent one of the word lines.

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Allentown, PA, United States of America

Ronald James Wozniak