59 results about "Resistance drift" patented technology

A voltage compensation circuit, a multi-level memory device with the same, and a voltage compensation method for reading the multi-level memory device are provided. When a memory cell is read, a reference voltage applied to the memory device is adjusted according to variation of characteristics of a drift resistance of a reference cell. The increased value of the reference voltage (i.e. a voltage difference) corresponds to a resistance variation caused by a drift condition. The drift compensation mechanism is adaptive to a compensation circuit of a read driver of the memory device, which can compensate variation of the voltage level when data is read from the memory cell. When the resistance drift occurs, a drift amount is calculated and is added to the reference voltage, in order to avoid the error in judgement caused by the resistance drift when the stored data is read out.

A method and apparatus are provided for implementing enhanced data partial erase for multi-level cell (MLC) memory using threshold-voltage-drift or resistance-drift tolerant moving baseline memory data encoding. A data partial erase for data written to the MLC memory using threshold-voltage-drift or resistance-drift tolerant moving baseline memory data encoding is performed, and a data re-write after the partial erase to the MLC memory is performed using threshold-voltage-drift or resistance-drift tolerant moving baseline memory data encoding. A data partial erase cycle includes a duration and voltage level based upon a degradation of the MLC memory cells.

A method and system are provided for high-speed, laser-based, precise laser trimming at least one electrical element along a trim path. The method includes generating a pulsed laser output with a laser, the output having one or more laser pulses at a repetition rate. A fast rise/fall time, pulse-shaped q-switched laser or an ultra-fast laser may be used. Beam shaping optics may be used to generate a flat-top beam profile. Each laser pulse has a pulse energy, a laser wavelength within a range of laser wavelengths, and a pulse duration. The wavelength is short enough to produce desired short-wavelength benefits of small spot size, tight tolerance, high absorption and reduced or eliminated heat-affected zone (HAZ) along the trim path, but not so short so as to cause microcracking. In this way, resistance drift after the trimming process is reduced.

The invention discloses a negative temperature coefficient (NTC) material utilized at a high temperature, and a preparation method thereof. The NTC material comprises 2 to 10 wt% of La2O3, 5 to 20 wt% of ZrO2, and the rest of Ni0.6Mn1.8Al0.6O4. In the invention, oxides which comprise MnO2, NiO and Al2O3 and are traditional materials for preparation of NTC materials are utilized as base materials;a rare earth oxide La2O3 is added into the base materials to improve a stability of the base materials and reduce a ageing rate; and simultaneously, non-conducting ZrO2 is added into the base materials to improve a resistivity of the base materials and an activation energy thereby improving a constant B of the base materials. The NTC material can be utilized at a temperature more than 400 DEG C, and has a room temperature resistivity of 27900 to 64520 omega cm, a constant B of 4529 to 7895 K and a resistance drift rate of 0.6 to 2.3%.

The invention discloses a negative temperature coefficient two-phase composite heat-sensitive material and a method for preparing the same characterized by mixing and milling the copper acetate, ferric oxalate, manganese acetate, nickel acetate and oxalate according to the mol ratio of 0.2-0.6: 1: 3.48-3.08: 1.32: 7.2, calcining the mixture after drying, mixing the prepared powder with partial stable cubic zirconia powder according to the mol ratio of 1: 1.5-4, getting two-phase composite powder after milling and drying, getting the negative temperature coefficient material with a relative density more than 94% after sintering. The material has a stable structure, a sintering temperature between 1200 and 1250 DEG C, a higher mechanical strength than the single-phase spinel ceramic, a B value less than 2800K, a resistivity of 1000omega.cm, a resistance drift less than 3% when accelerated ageing 1000 hours at 150 DEG C, a very good NTC property between -60 DEG C to +50 DEG C, and is suitable for the negative temperature coefficient heat sensitive sensor material in the modern aerostat.

Resistance drift can be addressed by refreshing the nonvolatile memory cells and reference cells. Different approaches include performing the refresh upon a program operation, and upon satisfaction of a condition after the program operation. Refreshes are performed on a reference resistance stored in a reference cell that can be compared by a sense amplifier to the resistance stored in a memory cell. In one approach, upon programming the first memory cell, a stored refresh status is updated to indicate that the first resistance of the first memory cell and the first reference resistance of the first reference cell are to be refreshed upon satisfaction of a condition. In another approach, upon programming the first memory cell, the first reference cell is programmed.

The invention belongs to the technical field of film resistance strain gauges and provides a high-temperature film half-bridge resistance strain gauge with a temperature self-compensation function and a preparation method of the high-temperature film half-bridge resistance strain gauge. The high-temperature film half-bridge resistance strain gauge is suitable for a high-temperature environment in which the in-situ temperature cannot be directly measured or the temperature is in a dynamic fluctuation state. The half-bridge resistance strain gauge comprises a nickel-based alloy substrate, a buffering layer, an insulating layer, a functional layer and a protective layer which are sequentially stacked from bottom to top; the functional layer is composed of two graphical strain sensing units with the same structure; the two graphical strain sensing units are vertical to each other to jointly form a half-bridge structure; apparent strain errors caused by temperature fluctuation (change) and drifting strain errors caused by resistance drifting of a sensing layer in a testing process can be effectively self-compensated by connecting the film half-bridge resistance strain gauge into a Wheatstone bridge circuit, so that the testing precision and accuracy of the strain gauge are improved; in addition, the high-temperature film half-bridge resistance strain gauge with the temperature self-compensation function is simple in preparation process, low in preparation cost and beneficial to industrial production.

The invention relates to a high-stability phase change memory cell and a preparation method thereof. The high-stability phase change memory cell comprises a substrate layer, an electrode material, a dielectric isolation material, a phase change material region and a transition layer material between the phase change material and the dielectric isolation material. The phase change memory unit formed in the invention can inhibit growth of phase change material grains, improve the thermal stability of a phase change memory, effectively inhibit diffusion and volatilization of each element in the phase change material, reduce the resistance drift coefficient and reduce the power consumption of a device.

Provided is a resistance variable memory device and a method for operating same. The resistance variable memory device has a phase change material between a top electrode and a bottom electrode. In the method for operating a resistance variable memory, the write current is applied in a direction from the top electrode to the bottom electrode, and the read current is applied in a direction from the bottom electrode to the top electrode. The phase change material is programmed by applying the write current, and a resistance drift of the phase change material is restrained by applying the read current.

The invention relates to a high-stability NTC (negative temperature coefficient) thermistor suitable for a medium-temperature zone and a preparation method of the thermistor. The thermistor comprises oxides of four metallic elements including Co, Mn, Fe and Zn, the oxides are subjected to preparation with a coprecipitation method, forming, sintering, slicing, electrodefiring, cutting and packaging, then the high-stability NTC thermistor suitable for the medium-temperature zone is obtained, the standard resistance of the thermistorat the temperature of 25 DEG C ranges from 50-180 kilohms, and the material constant ranges from 3,990 K to 4.270 K. The thermistor device has the standard resistance and material constantsuitable for the medium-temperature zone, can be applied to temperature measurement, control, compensation and the like of equipment such as an automobile, an air conditioner, a microwave oven and the like and has very good stability, consistency and interchangeability, the resistance drift rate is smaller than 0.1% after the thermistor is aged for 1,000 h at the temperature of 150 DEG C, the stability of the conventional NTC thermistor can be improved greatly, the measurement accuracy of the NTC thermistor can be improved, and the service life of the NTC thermistor can be prolonged.

The invention discloses a diagnosis method for diagnosing the sampling resistance drift, a diagnosis system and a digital control system. The diagnosis method comprises the following steps of (1) constructing sampling circuits Uhx and Ux, and acquiring the sampling circuits; (2) carrying out threshold comparison on the Uhx and the Ux to obtain compared output signals; (3) based on the output signals, acquiring the diagnosis result of the sampling resistance drift. The diagnosis system comprises a sampling module and a diagnosis module. The sampling module is used for acquiring a Uhx signal and a Ux, and transmitting the Uhx signal and the Ux to the diagnosis module respectively. The diagnosis module is used for comparing the Uhx signal with the Ux, and obtaining an output signal according to the comparison result. According to the invention, the sampling resistance drift faults of analog input can be diagnosed. Therefore, the predictability of signal input and the reliability of a verification and acquisition channel circuit are guaranteed. The method is novel, unique, practical and applicable.

The invention discloses a high-reliability phase change material, which is a superlattice-like phase change material layer formed by circularly and alternately overlapping first phase change materiallayers and second phase change material layers, wherein a superlattice-like interface is formed between the first phase change material layer and the second phase change material layer, the first phase change material layer is Sb2Te3 as an induction layer, the second phase change material layer is Ge15Te85, and at least three layers of the first phase change material layers and the second phase change material layers are circularly and alternately overlapped. The amorphous Sb2Te3 layer requires low energy for crystallization, stable lattice orientation is easy to form, the selected Sb2Te3 layer can thus be used as the induction layer, the amorphous Ge15Te85 layer has a higher phase change speed in the phase change process, and rapid crystallization of the whole phase change material can bepromoted; in addition, in the energy band structure of the selected Ge15Te85 layer, the defect state is mainly located in the local state of the band tail instead of the defect energy level near theFermi level in the band gap, resistance drift caused by relaxation of the defect energy level is avoided, and therefore the phase change speed is higher in the phase change process.

The invention discloses an NTC thermistor chip material, a chip, a resistor and a sensor, and making methods thereof, and belongs to the field of thermistors. The material comprises, by weight, 1000-1200 parts of Mn3O4, 95-105 parts of Co2O3, 190-210 parts of NiO and 590-610 parts of Fe2O3. The NTC thermistor made by using the NTC thermistor chip material has the advantages of difficult breakdown by current, difficult resistance drift and long service life.

The invention discloses an NTC thermistor chip material, a chip, a thermistor, a sensor and a preparation method and belongs to the field of thermistors. The material comprises following components, by weight, 550-570 parts of Mn3O4, 55-65 parts of Co2O3, 690-710 parts of NiO and 790-810 parts of Fe2O3. An NTC thermistor prepared from the NTC thermistor chip material is not liable to be broken-down by a current, is not liable to cause resistance drift, and is long in service life.