Micron Technology Incorporated

Seagate Technology Incorporated

Round Rock Research, LLC

Kang Yong Kim

Tyler J Gomm

Chulmin Jung

Jongtae Kwak

Dong Myung Choi

Dimitar Velikov Dimitrov

Yiran Chen

Hai Li

Hongyue Liu

Henry F Huang

Yong Lu

Gary M Johnson

Young Pil Kim

Jeffrey P Wright

Hyunyoo Lee

Keun Soo Song

This document describes apparatuses and techniques for termination for single-ended (SE) mode operation of a memory device. In various aspects, a termination circuit can terminate an unused signal line of a differential pair to a ground or power rail using a switch element when operating in the SE mode. The termination circuit may also disconnect the unused signal line from a first input of a differential amplifier and connect a reference voltage to the first input of the differential amplifier. Based on the reference voltage, the differential amplifier amplifies an SE signal received using another signal line of the differential pair at a second input of the differential amplifier to provide a clock signal for memory operations. Thus, the termination circuit may reduce an amount by which noise associated with the unused signal line affects the differential amplifier when the memory device operates in SE mode.

Termination for single-ended mode

A circuit and method for generating an active output signal in response to detecting N events, which are represented by an event signal. A counter circuit is configured to increment and decrement through a sequence of values in response to the event signal. Detection logic coupled to the counter circuit is configured to detect at least first and second values of the sequence. The detection logic is further configured to generate the active output signal and switch to detecting the second value in response to detecting the first value and generate the active output signal and switch to detecting the first value in response to detecting the second value. The first and second values are separated by N counts.

Continuous high-frequency event filter

A spin-transfer torque memory apparatus and self-reference read schemes are described. One method of self-reference reading a spin-transfer torque memory unit includes applying a first read current through a magnetic tunnel junction data cell and forming a first bit line read voltage. Then applying a low resistance state polarized write current through the magnetic tunnel junction data cell, forming a low second resistance state magnetic tunnel junction data cell. A second read current is applied through the low second resistance state magnetic tunnel junction data cell to forming a second bit line read voltage. The method also includes comparing the first bit line read voltage with the second bit line read voltage to determine whether the first resistance state of the magnetic tunnel junction data cell was a high resistance state or low resistance state.

Spin-transfer torque memory self-reference read method

An input-output line sense amplifier configured to drive input data signals over an input-output signal line to an output driver circuit, the input-output line sense amplifier having an output driver stage having a plurality of different programmable output drive capacities to tailor the output drive of the sense amplifier.

Input-output line sense amplifier having adjustable output drive capability

A memory array includes a plurality of magneto-resistive changing memory cells. Each resistive changing memory cell is electrically between a source line and a bit line and a transistor electrically between the resistive changing memory cell and the bit line. The transistor has a gate electrically between a source region and a drain region and the source region being electrically between the r magneto-resistive changing memory cell and the gate. A word line is electrically coupled to the gate. A bit line charge accumulation sensing for magneto-resistive changing memory is also disclosed.

Bit line charge accumulation sensing for resistive changing memory

A system and method are disclosed to generate and terminate clock shift modes during initialization of a synchronous circuit (e.g., a delay-locked loop or DLL). Upon initialization, the DLL is entered into a ForceSL (Force Shift Left) mode and an Onlx mode (i.e., left shifting on each clock cycle). The feedback clock that tracks the phase of the reference clock (derived from the system clock) is initially delayed in a coarse phase detector prior to applying it to the coarse phase detection window. Two delayed versions of the feedback clock are sampled by the reference clock to generate a pair of phase information signals, which are then used to establish an advanced phase equal (APHEQ) signal. The APHEQ signal is used to terminate the ForceSL and Onlx modes, thereby preventing wrong ForceSL exit due to clock jitter or feedback path overshooting during Onlx exit, and resulting in faster DLL locking time.

DLL phase detection using advanced phase equalization

Disclosed herein is a VDL/DLL architecture in which the power supply to the VDL, VccVDL, is regulated at least as a function of the entry point of the input signal (ClkIn) into the VDL. Specifically, VccVDL is regulated to be higher when the delay through the VDL is relatively small (when the entry point is toward the right (or minimum delay) edge of the VDL) and is reduced when the delay is relatively high (when the entry point is toward the left (or maximum delay) edge of the VDL). This provides for graduated delays across the stages of the VDL, but without the need to design each stage separately. Other benefits include a VDL/DLL design operable over a wider range of frequencies, and a reduced number of stages, including a reduced number of buffer stages. Moreover, when the disclosed technique is used, buffer stages may be dispensed with altogether. Additionally, the disclosed VDL architecture can be used in any situation where it might be advantageous to delay a signal through a variable delay as a function of VDL entry point.

Control of a variable delay line using line entry point to modify line power supply voltage

A clock synchronization system and method avoids output clock jitter at high frequencies and also achieves a smooth phase transition at the boundary of the coarse and fine delays. The system may use a delay line configured to generate two intermediate clocks from the input reference clock and having a fixed phase difference therebetween. A phase mixer receives these two intermediate clocks and generates the final output clock having a phase between the phases of the intermediate clocks. The shifting in the delay line at high clock frequencies does not affect the phase relationship between the intermediate clocks fed into the phase mixer. The output clock from the phase mixer is time synchronized with the input reference clock and does not exhibit any jitter or noise even at high clock frequency inputs.

Seamless coarse and fine delay structure for high performance DLL

A spin-transfer torque memory apparatus and self-reference read schemes are described. One method of self-reference reading a spin-transfer torque memory unit includes applying a first read current through a magnetic tunnel junction data cell and forming a first bit line read voltage, the magnetic tunnel junction data cell having a first resistance state and storing the first bit line read voltage in a first voltage storage device. Then applying a low resistance state polarized write current through the magnetic tunnel junction data cell, forming a low second resistance state magnetic tunnel junction data cell. A second read current is applied through the low second resistance state magnetic tunnel junction data cell to forming a second bit line read voltage. The second bit line read voltage is stored in a second voltage storage device. The method also includes comparing the first bit line read voltage with the second bit line read voltage to determine whether the first resistance state of the magnetic tunnel junction data cell was a high resistance state or low resistance state.

A system and method for trimming an unadjusted forward delay of a delay-locked loop (DLL) and trimming a duty cycle of first and second output clock signals provided by a DLL. For trimming an unadjusted forward delay, delay is added to one of a feedback clock signal path and an input clock signal path and a feedback clock signal is provided from the feedback clock signal path and an input clock signal is provided from the input clock signal path for phase comparison. For trimming a duty cycle of first and second output clock signals, one of a first delayed input clock signal and a second delayed input clock signal is delayed. The first and second delayed input clock signals are complementary. The delayed clock signal and the other clock signal are provided as the first and second output clock signals.

Apparatus and method for trimming static delay of a synchronizing circuit

A method is disclosed for controlling an output impedance of an electronic device of the type having an impedance control terminal to which an external load is to be connected such that a predetermined value of the voltage at the impedance control terminal controls the output impedance of the device. The method is comprised of comparing a reference voltage to a voltage at the impedance control terminal. A variable count signal representing a count value is produced in response to the comparing. The impedance of a variable impedance circuit is varied in response to the count signal, wherein the impedance of the variable impedance circuit controls the voltage at the impedance control terminal. A device connected in parallel with the variable impedance circuit is periodically operated to change (increase/decrease) the impedance of the variable impedance circuit. An apparatus for performing the method is also disclosed. Because of the rules governing abstracts, this abstract should not be used to construe the claims.

Method and apparatus for high resolution ZQ calibration

A delay lock loop having improved timing control of input signals. Specifically, a fine delay block is provided having feedback loops therein such that the fine delay block is self tuning. The output of the fine delay block may be implemented to control a coarse delay block in a delay lock loop.

Self-timed fine tuning control

A system and method are disclosed to generate and terminate clock shift modes during initialization of a synchronous circuit (e.g., a delay-locked loop or DLL). Upon initialization, the DLL is entered into a ForceSL (Force Shift Left) mode and an On1x mode (i.e., left shifting on each clock cycle). The feedback clock that tracks the phase of the reference clock (which, in turn, is derived from the system clock) is initially delayed in a coarse phase detector prior to applying it to the coarse phase detection window. Two delayed versions of the feedback clock are sampled by the reference clock to generate a pair of phase information signals, which are then used to establish an advanced phase equal (APHEQ) signal. The APHEQ signal advances onset of the PHEQ (phase equalization) phase and is used to terminate the ForceSL and On1x modes, thereby preventing wrong ForceSL exit due to clock jitter or feedback path overshooting during On1x exit. The avoidance of wrong ForceSL exit and On1x overshooting problems further results in faster DLL locking time.

A memory array includes a plurality of magneto-resistive changing memory cells. Each resistive changing memory cell is electrically between a source line and a bit line and a transistor electrically between the resistive changing memory cell and the bit line. The transistor has a gate electrically between a source region and a drain region and the source region being electrically between the magneto-resistive changing memory cell and the gate. A word line is electrically coupled to the gate. A bit line charge accumulation sensing for magneto-resistive changing memory is also disclosed.

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Boise, ID, United States of America

Kang Yong Kim