International Business Machines Corporation

Cypress Semiconductor Corporation

Nan Ya Technology Corporation

Other

Siemens Aktiengesellschaft

Richard Michael Parent

David G Chapman

Matthew R Wordeman

Louis L Hsu

Ryan Andrew Jurasek

Russell J Houghton

Oliver Kiehl

Timothy E Fiscus

Rajiv V Joshi

Louis Lu-Chen Hsu

Li-Kong Wang

Duane E Galbi

Dave Eugene Chapmen

Adam B Wilson

Lin Ma

Anupam I Arora

Benjamin James Stembridge

A reference voltage generation circuit for generating a reference voltage that can adaptively depend on temperature and process includes: a comparator, having a process, temperature and voltage (PVT) insensitive reference as a first input, and a feedback of the output as a second input, for generating a voltage reference output; a first resistor, coupled to the output of the operational amplifier; a second and a third variable resistor coupled in parallel, and coupled between the first resistor and ground; and a transistor, coupled between the third variable resistor and ground.

Temperature and process driven reference

A chip system that has reduced power consumption under specific operational modes includes: a DDR3 chip that includes: a plurality of pads, disposed at the center of the DDR3 chip; and an array of banks, each bank having a specific logical address, surrounding the pads. The chip system further includes: a clock, coupled to the DDR3 chip, for controlling a rate of data transmission; and a memory controller, coupled to the clock, for coordinating transmitted data with relevant processes, and for selectively reassigning the bank logical addresses according to a specific operational mode.

Bank re-assignment in chip to reduce IR drop

The configurations of a DRAM positive wordline voltage compensation device and a voltage compensating method thereof are provided in the present invention. The proposed device includes a comparator having a first input terminal receiving a positive wordline voltage feedback signal, a second input terminal receiving a compensating reference of array device threshold voltage and an output terminal generating a first enable signal, an oscillator receiving the first enable signal and generating an oscillating signal when the first enable signal is active and a charge pump having a first input terminal receiving a second enable signal, a second input terminal receiving the oscillating signal and an output terminal generating a positive wordline voltage being a sum of a bitline high voltage, an array device threshold voltage and a voltage margin.

DRAM positive wordline voltage compensation device for array device threshold voltage and voltage compensating method thereof

A method for reducing leakage current of a memory device includes supplying a first voltage to a main wordline driver, supplying a second voltage greater than the first voltage to a local wordline driver, and employing a transistor in the local wordline driver with a threshold voltage greater than a specific value.

Method for reducing leakage current of a memory and related device

A method for reducing power consumption in a volatile memory includes switching off a bitline voltage provider according to a leakage control signal when a bitline array corresponding to the bitline voltage provider is dysfunctional due to a wordline to bitline short, controlling connections between a plurality of first bitline arrays corresponding to the bitline voltage provider and a plurality of sense amplifiers according to an access control signal, controlling connections between a plurality of second bitline arrays corresponding to the plurality of first bitline arrays and the plurality of sense amplifiers according to the access control signal, and providing power to the plurality of corresponding sense amplifiers according to the access control signal.

Method for reducing power consumption in a volatile memory and related device

A wordline driver circuit can include single stage level shifters to translate a low voltage level (VGND to Vcc) to a high voltage level (Vnwl to Vpp). A wordline driver can further include a two-stage discharge circuit to pull down a wordline from a boosted high voltage Vpp to a boosted low voltage Vnwl. A two-stage discharge circuit can include (i) a first discharge path that can pull the wordline toward a first low voltage VGND; and (ii) a second discharge path that can pull the wordline toward a lower boosted low voltage Vnwl. Initially discharging a wordline to a first low voltage can reduce the amount of charge injected into a boosted low voltage Vnwl supply. A two-stage discharge circuit can be self timed or externally timed.

Dual-voltage wordline drive circuit with two stage discharge

In one arrangement, a semiconductor memory device can include a sense amplifier circuit () having drive high transistors (P/P), drive low transistors (N/N) and equalization transistors (N-N). Such transistors can have a body bias (VbiasN, VbiasP) that varies according to the operation conditions of the semiconductor memory device. Such variations can include any of: manufacturing process variations, operating temperature, or operating voltage.

Sense amplifier circuit and method of operation

A semiconductor device memory device () can include a sense amplifier () enabled according to a first sense signal (setn) and a second sense signal (setp). In a sense operation, a first sense signal (setn) can be driven to a first, below ground potential. Subsequently, in the same sense operation, the first sense signal (setn) can be raised and maintained at a ground potential. Such an approach can substantially eliminate a sense amplifier stall condition that can occur under low temperature and/or low voltage operation. According to another aspect of the embodiments, a more negative logical '0' value can be written back into the memory cell during an access and/or refresh operation. This more negative value is available due to the below ground level provided during a sense operation.

Sense amplifier circuit and method

A defect current contribution elimination technique may be suitable for dynamic random access memories (DRAMs) and other memory devices. A defect current can be eliminated by using an isolation circuit () between bitlines (-and-) and an associated sense amplifier circuit (). Isolation circuit () can be controlled by programmable elements, such as fusible links, which are blown at wafer test to isolate the defective bitlines from the sense amplifier circuit. Isolated, defective bitlines may initially float, but based upon the type of defect, such bitlines can be resistively tied to another element, and as a result no DC current will flow. According to another implementation, controllable devices are placed between wordlines () and the wordline driver circuits (-). A current path through a defective wordline can be similarly cut-off.

Method and circuit for reducing defect current from array element failures in random access memories

A method for reducing power consumption during background operations in a memory array with a plurality of sections comprising the steps of (i) controlling the background operations in one or more sections of the memory array in response to one or more control signals and (ii) presenting the one or more control signals and one or more decoded address signals to one or more periphery array circuits of the one or more sections.

Method and architecture for reducing the power consumption for memory devices in refresh operations

A method for reducing power consumption during background operations in a memory array with a plurality of sections comprising the steps of (i) enabling the background operations in one or more sections of the memory array when one or more control signals are in a first state and disabling the background operations in one or more sections of the memory array when the one or more control signals are in a second state and (ii) generating the one or more control signals in response to an address signal.

A clock system is provided capable of using an external system clock for driving at least one charge circuit of a semiconductor memory unit for restoring and refreshing a data array of the memory unit. The clock system, in one embodiment, includes a plurality of control circuits each having a clock select circuit which has as an input the external system clock, an internal clock generator circuit for generating an internal system clock, and a multiplexer. The multiplexer has as inputs an output of the clock select circuit, i.e., the external system clock, and an output of the internal clock generator circuit, i.e., the internal system clock. The multiplexer outputs either the external system clock or the internal system clock to the at least one charge circuit according to at least one control signal transmitted by a central processing unit to the clock select circuit.

Clock system for an embedded semiconductor memory unit

Dynamic random access memory chips (DRAMs) in a computer memory system are made to be more available for access by a processor even though an autorefresh cycle may be in progress when the processor attempts to access the memory system. A DECODED AUTOREFRESH mode is defined which allows refresh of certain banks of the DRAM only. The bank addresses from the external DRAM controller select the bank where the AUTOREFRESH has to be performed. The DRAM controller circuitry makes sure that every bank of the DRAM gets a refresh command often enough to retain information.

Decoded autofresh mode in a DRAM

A complete solution to block noise from eDRAM macro to the analog core, and vice verse, in a system-on-chip IC design. Specifically, there is provided a first isolated triple well structure formed in the IC for reducing noise component resulting from operative elements of a DC generator circuit fabricated therein; and, a second isolated triple well structure formed in the IC for reducing noise component resulting from operative elements of a noise sense amplifier bank and DRAM arrays fabricated therein. A power supply source is provided for supplying power to each DC generator circuit, noise sense amplifier bank and DRAM array; as is a power bus for providing power and a separate power bus for providing a ground to each of the DC generator circuit, and the noise sense amplifier circuit and DRAM array components. In this manner, noise contamination with noise sensitive devices in said IC is reduced and, further noise contamination of the DRAM array as sourced from the IC is reduced.

System and method for preventing noise cross contamination between embedded DRAM and system chip

A system and method for considerable reduction of power consumption in memory circuits implementing Vbb (array body bias) and Vwl (negative word line) voltage generators. The system comprises switching off the negative WL generator during sleep or standby mode, so that no power is consumed. A relaxed refresh operation is carried out and the negative WL is powered by the Vbb generator. The noise coupled to the negative WL supply from BL swing is reduced due to the joint Vbb-Vwl decoupling scheme. In the active mode, the Vbb and Vneg are separated to avoid any cross-over noise and to maintain design flexibility. During power-on period, the ramp-up rate of Vbb level is improved by the Vwl generator. The advantages may be summarized as: (1) simpler Vbb generator design, (2) much smaller Vbb generator size, (3) reduced Vbb power, (4) no stand-by current from Vwl generator, (5) low decoupling noise for Vwl level during stand-by or sleep mode, (6) enhanced ramp-up rate for Vbb during power-on, (7) no cross-over noise between Vbb and Vwl during active mode, and (8) design flexibility of Vbb and Vwl in the active mode. The principles and advantages of the invention may be applied to any two or more DC generator systems, negative or positive.

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Shelburne, VT, United States of America

Richard Michael Parent