111results about How to "Low linearity" patented technology

The invention discloses a power tube drive method and a power tube drive circuit. The power tube drive method and the power tube drive circuit are applied to a direct-current solid power controller. The power tube drive circuit comprises a charging and discharging constant current source, a corresponding control switch, a not gate, and a feedback capacitor connected between the grid electrode and the drain electrode of a power tube in a bridging mode. In the turning on and turning off process of the direct-current solid power controller, the constant current source is controlled to charge and discharge the feedback capacitor, and the feedback capacitor feeds voltages of the drain electrode and the source electrode of the power tube back to the power grid electrode. The invention further discloses the direct-current solid power controller comprising the power drive circuit. According to the power tube drive method and circuit, and the direct-current solid power controller, the power tube can be turned on and turned off at a low and constant switching speed, load voltages are increased or decreased in a linear mode, and the rate of increasing and decreasing is adjustable. The power tube drive method and the power tube drive circuit are suitable for conventional Si MOSFETs and IGBTs, and also are suitable for Sic and GaN field control type power tubes like JFETs, MOSFETs and IGBTs. The drive circuit is simple and reliable, easy to integrate, and low in cost.

Provided are a polyimide that demonstrates low coefficient of hygroscopic expansion and low water absorption coefficient when used as an insulation film, as well as an ester group-containing tetracarboxylic acid dianhydride expressed by the general formula below, and a novel polyesterimide precursor derived therefrom and polyesterimide, for use in the production of such polyimide:In the formula, each R is independent and represents a straight or branched-chain alkyl group with 1 to 6 carbon atoms or straight or branched-chain alkoxyl group with 1 to 6 carbon atoms, n is an integer of 0 to 4, and m is an integer of 2 to 4, with the proviso that if m=2, n is an integer of 1 to 4.

A deep reactive ion etching method belongs to the technical field of manufacturing of semiconductors. The method comprises an etching step and a polymer-depositing step which are alternately performed, wherein the conversion between a first process condition employed by the etching step and a second process condition employed by the polymer-depositing step is realized by a gradually changed conversion method. The side wall of a deep through hole etched by the deep reactive ion etching method has good smoothness; and the etching efficiency of the method is high.

The invention discloses a linear power amplification circuit based on the simulation of predistortion, comprising a predistortion amplifier, a first temperature-controlled attenuator, a simulate predistorter, a second temperature-controlled attenuator, a push-pull amplifier, and a last stage high-power amplifier which are sequentially connected. The invention also discloses a method to use the circuit: the simulate predistorter circuit which has relatively simple topological structure is added to produce a distortion signal of a predistortion signal balanced power amplifier; a matching circuit and a bias voltage of a power tube of the push-pull amplifier and that of the last stage high-power amplifier are adjusted to make the two power tubes complement in amplitude and phase to achieve the predistortion effect and to enable better linearity of the RF output signal. The invention is simple in circuit structure, high in working efficiency, low in cost and occupies little PCB area, which is extremely suitable for the multi-carrier linear power amplification circuits in the TD-SCDMA stations and the repeaters systems.

The invention discloses a field programmable gate array (FPGA)-based temperature control and temperature compensation circuit device for a silicon microgyroscope. The FPGA-based temperature control and temperature compensation circuit device comprises a microgyroscope integrated with a miniature heater and a temperature sensor, an interface circuit and an FPGA processing circuit; a temperature control loop, a drive control loop and a detection control loop are formed by mutual connection. The chip-level temperature control and temperature compensation of the silicon microgyroscope are achieved by using the temperature sensor and the miniature heater integrated inside the microgyroscope. The FPGA-based temperature control and temperature compensation circuit device has the advantages of high sensitivity, good repeatability, small inertia, high reliability of temperature information, small power consumption, high control accuracy and the like, the effect of temperature drift of an analogue circuit is reduced by an FPGA-based digital temperature control and temperature compensation platform, meanwhile, a digitalized platform is flexible to adjust parameters, and strong in function, kinds of complicated temperature control and temperature compensation algorithms can be flexibly achieved, and optimization of the performance of the system is facilitated.

The invention discloses a method for modulating high-efficiency and self-adaptive oscillation frequency of a switching power supply. The method is characterized in that the modulation method of the switching power supply is controlled by the magnitude of a load current and can obtain high-efficiency and low-output ripple wave good capability at the same time, and the working frequency of the switching power supply is kept at a set higher switching frequency in the case that the switching power supply is under the steady control state of a high output current or a full load; the working frequency is linearly reduced along with the load current in the manner of positive correlation when the load is reduced; and the working frequency keeps at a set lower switching frequency when the load is further reduced at or below a set lower load current. Therefore, the switching frequency can be linearly reduced by the switching power supply within some range from underloading to noloading, so that the switching efficiency is greatly improved, and the abrupt increase and decrease of the output voltage caused by the abrupt change of the load can be further avoided. Furthermore, a system can be prevented from entering into a voice frequency zone to work by limiting the minimum frequency of the switching power supply, so that the possibility of generating mechanical vibration and voice frequency noise of the system can be eliminated.

The invention discloses a rotation self-stopping convergent type rotary seal structure. The rotation self-stopping convergent type rotary seal structure comprises a stator inner ring and a stator outer ring. A high-pressure rotation stopping cavity is formed between the inner surface of the stator outer ring and the outer surface of the stator inner ring, and a plurality of seal teeth are arranged on the inner surface of the stator outer ring. The stator inner ring is provided with low-pressure rotation stopping cavities and rotation stopping jet holes. The jet angle alpha of the rotation stopping jet holes is greater than or equal to 30 degrees but smaller than or equal to 60 degrees, and high-speed jet flow with the rotation direction opposite to that of a rotation component is formed inside the low-pressure rotation stopping cavities. The cavity depths of convergent type seal cavities in the structural forms of labyrinth annular cavities, bag type cavities, round hole cavities, hexagonal honeycomb cavities and the like in the stator inner ring are gradually decreased in the flowing direction. Upstream seal teeth of the seal cavities in the stator inner ring are provided with tooth crest grooves. Convergent type seal gaps between the seal cavities in the stator inner ring and the outer surface of the rotation component are linearly reduced in the flowing direction. According to the rotation self-stopping convergent type rotary seal structure, circumferential rotational flow in the seal cavities can be reduced effectively, effective damping and effective rigidity of the rotary seal are improved, and the static and dynamic stability of a rotor system is enhanced.

The invention provides a passive optical network, device and method for adjusting logical splitting ratio of an optical branching device. The passive optical network comprises an OLT, the optical branching device, multiple ONUs and optical fibers connected among the OLT, the optical branching device and the multiple ONUs; the OLT is used for detecting the physical splitting ratio and the logical splitting ratio of the passive optical branching device, the OLT and the system parameters of the ONUs in real time, monitoring commands are transmitted to each ONU through the optical branching device, and motoring results returned by the ONUs are received through the optical branching device; according to the physical splitting ratio and the logical splitting ratio of the passive optical branching device, the OLT, the system parameters of the ONUs and the monitoring results returned by the ONUs, the wave length of an optical signal is adjusted for changing the logical splitting ratio of the optical branching device; the ONUs are used for conducting monitoring according to the received motoring commands and transmitting the monitoring results to the OLT through the optical branching device. By the application of the passive optical network, device and method for adjusting the logical splitting ratio of the optical branching device, the dynamic reconfiguration of the passive optical network can be achieved.

The invention discloses a full-automatic collecting liquid-plastic limit combined measuring system. The full-automatic collecting liquid-plastic limit combined measuring system comprises a liquid-plastic limit combined measuring instrument and a computer, wherein the liquid-plastic limit combined measuring instrument comprises a mounting frame, a cone head, an electromagnet, a displacement transducer, a displacement display screen, a CPU (central processing unit), a communication module, a control switch and a specimen cup; the specimen cup is placed on the mounting frame; the electromagnet, the displacement transducer, the displacement display screen, the CPU, the communication module and the control switch are arranged on the mounting frame; the cone head is arranged above the opening of the specimen cup and is adsorbed on the electromagnet; the displacement transducer is connected with the computer in a signal manner through the CPU and the communication module; and a double logarithmic chart is stored in the computer. The full-automatic collecting liquid-plastic limit combined measuring system provided by the invention can be used for acquiring, measuring and reading data in a full automatic manner and drawing a curve, so that the accuracy of the test data is improved, the work amount of experimenters is reduced, the cost of human resources is reduced, and the test efficiency is improved.

Embodiments of the present application relate to a fingerprint detecting device and a terminal device having a fingerprint recognition function. The terminal device includes: a glass cover plate (110)for providing a touch interface for fingerprint recognition of a finger; a liquid crystal panel (120) located under the glass cover plate (110) for displaying an image; a backlight module (130) located under the liquid crystal panel (120) for providing a light source for the liquid crystal panel (120) to display the image; and a light emitting component (140) located below the glass cover (110) and unobstructed with the liquid crystal panel (120) and used for emitting light and illuminating the finger to produce return light for the terminal device to perform the fingerprint recognition on the finger. The fingerprint detecting device and the terminal device having the fingerprint recognition function of the embodiments of the present application can implement fingerprint recognition undera LCD screen.

The invention discloses an N-type super-junction transverse double-diffusion metal oxide semiconductor tube, which comprises a P-type substrate, wherein the P-type substrate is provided with a super-junction structure and a P-type body region; the super-junction structure consists of an N-type epitaxial layer and a P-type semiconductor region embedded therein; the P-type body region is provided with an N-type source region, a P-type body contact region and a grid oxide layer; the super-junction structure is provided with an N-type drain region; a first type field oxide layer is arranged above the super-junction structure and positioned in a region beyond the N-type drain region; a polycrystalline silicon grid is arranged above the grid oxide layer and extends to the upper part of the first type field oxide layer from the upper part of the grid oxide layer; a second type field oxide layer is arranged above the N-type source region, the P-type body contact region, the N-type drain region, the polycrystalline silicon grid and the first type field oxide layer; the N-type source region, the N-type drain region, the P-type body contact region and the polycrystalline silicon grid are all connected with a source metal lead, a grid metal lead and a drain metal lead; and the depth of the P-type semiconductor region in the super-junction structure is linearly reduced in the direction from the N-type source region to the N-type drain region.

The invention relates to an analog decision feedback equalizer which is used in a high-speed serial interface, and the analog decision feedback equalizer mainly adopts a high-frequency compensation circuit, an analog compensation signal generation circuit, a first analog adder, a first displacement comparator, a second displacement comparator, a third displacement comparator, a first output multiplexer, a second analog adder, a third analog adder, a second output multiplexer, an error register, a voting logic counter and a locked judgment circuit which are connected through ports. An analog signal to be processed is input by the high-frequency compensation circuit, after that, the analog signal and output of the analog compensation signal generation circuit compensate nodes through the first analog adder; the first and the second displacement comparators and the first output multiplexer are used for judging output data. The second and the third analog adders and the second output multiplexer constitute an error generating circuit. The analog decision feedback equalizer has lower requirements on linearity and absolute errors of the analog circuit, thereby saving design cost, having better linearity of the analog adders of the compensation circuit and causing no compensation errors.

The invention relates to a strain type multidirectional force transducer with a self-decoupling function, wherein the strain type multidirectional force transducer belongs to the field of a load sensor. The strain type multidirectional force transducer comprises a four-column type structure, a strain gauge and a compensating gauge. The four-column type structure has a structure in which four columns are placed between an upper disc and a lower disc, and the four columns are arranged in a manner that two random columns are in symmetry with the other two columns. The strain gauge and the compensating gauge abut against the columns. The manufactured device is sealed in a sleeve, and air in the sleeve is replaced by insert gas, thereby ensuring no moisture absorption or moistening and preventing long-term stability reduction of the device. According to the strain type multidirectional force transducer, the four-column type symmetrical structure and bridging signal separation technology are utilized so that the sensor has high self-decoupling performance, thereby realizing simultaneous measurement for aeroengine thrust vectors, namely three force amplitude components and three moments, supplying more reliable and comprehensive technological data support for a vector thrust engine testing experiment, realizing higher reliability in an engine thrust measurement method, and obtaining higher accuracy of the measured data.

A magnetic disk drive includes a magnetic disk and a femto slider. The magnetic disk has a minimum track linear velocity of 1 to 5 m / s. In one embodiment, the magnetic disk drive includes a negative pressure type femto slider and adopts a load / unload method. A gram load “GL” of a head suspension assembly HSA is set at a value exceeding about 3 mN and smaller than about 15 mN and a pitch static attitude “PSA” (deg) and pitch stiffness “Kp” (Nm / deg) satisfy the expression ((PSA×Kp) / GL)<0.25 mm. As a result, it is possible to prevent the femto slider from assuming a meta-stable flying high state referred to as a bi-stable height. Further, by setting the pitch static attitude “PSA” at a value of larger than 0 deg, it is possible to prevent the slider from assuming a state of meta-stable contact with the magnetic disk surface referred to as semi-stable drag.

The invention discloses a dual-mode millimeter wave broadband stacking low noise amplifier with low power consumption and high linearity. The dual-mode millimeter wave broadband stacking low noise amplifier comprises a two-stacking self-bias low noise amplification network, a feedback dual-mode high-linearity amplification network and a bias network. The dual-mode millimeter wave broadband stacking low noise amplifier disclosed by the invention adopts two transistors with different sizes to realize a serial stacking structure, and combines the self-bias technology to realize ultra-broadband noise matching, impedance matching and low power consumption; and meanwhile, a feedback dual-mode switching structure is adopted, so that the circuit has the switching capability in two modes, namely, high linearity and low power consumption, different usage requirements of users are met, and good broadband, gain and standing wave characteristics are obtained within the whole working frequency band.

A method for preparing nanometer porous pellumina which can regulate aperture and / or pitch of holes, which comprises the following steps: firstly, carrying out annealing and electrochemical polishing to an aluminum sheet, secondly, arranging the treated aluminum sheet in a constant-potential electrolytic cell, adding phosphorus acid solution as electrolyte, adding polyethylene glycol as adjusting agent, carrying out constant-potential anodic oxidation, then obtaining the nano-porous pellumina which can regulate aperture and / or pitch of holes, wherein the average molecular weight of polyethylene glycol is 400-2000, the mass percentage concentration n of the polyethylene glycol in the electrolyte is 0%<n<=50%, the concentration of the phosphorus acid in the electrolyte is 0.2-0.8 mole, and the electrolyzing time is 4-48h. Polyethylene glycol is adopted by the method as adjusting agent, effective adjusting to the aperture and the pitch of holes is realized, range of oxidizing electric potential is expanded through the chemical protection the electrochemical protection of polyethylene glycol, the used addition agent polyethylene glycol has the advantages of safety, environmental protection and low cost, therefore, the method is convenient to spread.

The invention discloses a P-type super-junction transverse double-diffusion metal oxide semiconductor tube, which comprises an N-type substrate, wherein the N-type substrate is provided with a super-junction structure and an N-type body region; the super-junction structure consists of a P-type epitaxial layer and an N-type semiconductor region embedded therein; the N-type body region is provided with a P-type source region, an N-type body contact region and a grid oxide layer; the super-junction structure is provided with a P-type drain region; a first type field oxide layer is arranged above the super-junction structure and positioned in a region beyond the P-type drain region; a polycrystalline silicon grid is arranged above the grid oxide layer and extends to the upper part of the first type field oxide layer from the upper part of the grid oxide layer; a second type field oxide layer is arranged above the P-type source region, the N-type body contact region, the P-type drain region, the polycrystalline silicon grid and the first type field oxide layer; the P-type source region, the P-type drain region, the N-type body contact region and the polycrystalline silicon grid are all connected with a source metal lead, a grid metal lead and a drain metal lead; and the depth of the N-type semiconductor region in the super-junction structure is linearly reduced in the direction from the P-type source region to the P-type drain region.

The invention discloses an unmanned aerial vehicle optimal speed scheduling method based on an actual model in wireless sensor network data acquisition. The method comprises three parts, namely scene information preprocessing, effective speed calculation of a "segment" and unmanned aerial vehicle flight speed setting. According to the invention, the sensor information is processed and the information of the "segment" is initialized; then, the effective speed of each "segment" according to parameters such as effective distance, effective time and the like is calculated; and finally, the obtained effective speeds is screened, and finally the optimal speed plan of the unmanned aerial vehicle is obtained.

The invention discloses a 5G communication anti-mismatch broadband low-noise amplifier. The 5G communication anti-mismatch broadband low-noise amplifier comprises two paths of high-linearity low-noiseamplification networks which are connected in parallel, an active bias network, a passive bias network, an RC negative feedback network, an input 45-degree phase shift network and an output 45-degreephase shift network. Two transistors with different sizes are adopted to form a series stacked structure to realize a low-noise amplification network, and an RC negative feedback network is combinedto realize ultra-wideband low noise, impedance matching and high linearity; meanwhile, a balanced synthesis structure is adopted to design an integral circuit; a phase shift network is added into theinput and the output. The load mismatch tolerance and the load change insensitivity of the amplifier are improved; the linearity index of the amplifier in a non-50 ohm system is improved, so that thewhole low-noise amplifier not only has good broadband, linearity, low power consumption and low noise amplification capacity in the non-50 ohm system, but also higher OIP3 performance is still kept inthe non-50 ohm system.

The invention discloses a low-temperature-resistant low-air-permeability silicon resin coating composition and a preparation method thereof. The preparation method comprises the following steps: firstly, preparing a trifunctional aryl silicon resin prepolymer, and carrying out copolymerization on the trifunctional aryl silicon resin prepolymer, hydroxyl silicone oil and fluorine-containing hydroxyl silicone oil to prepare hydroxyl-terminated fluorine-containing aryl silicon resin (R1SiO1.5)a(R22SiO)b(R2R3SiO)c(OH)d, wherein the (R1SiO1.5)a(R22SiO)b(R2R3SiO)c(OH)d has a T-shaped aggregate polysiloxane-D type linear polysiloxane block structure; and after the silicon resin is diluted by using a diluent, adding trialkoxysilane as a cross-linking agent and a titanium-containing or tin-containing compound as a catalyst, and performing uniform mixing to obtain the low-temperature-resistant low-air-permeability silicon resin coating composition. The composition coats the surface of a base material in a spraying, brush coating or dip-coating manner, and a low-temperature-resistant low-air-permeability silicon resin coating is obtained after room-temperature curing. The coating provided bythe invention can resist the low temperature of -70 DEG C for a long time and can be subjected to hot and cold circulation for 300 times at the temperature of -70 DEG C to 140 DEG C, and the oxygen permeation amount is smaller than 100 cm<3> / (m<2>*24 h*0.1 MPa).

The invention discloses a constant slope digital-to-time converter and a control method thereof, and the constant slope digital-to-time converter comprises a discharge load capacitor which is used forstoring charges so as to discharge and generate a voltage falling edge; a discharge current source which is used for determining the slope of the falling edge of the output voltage according to the discharge current of the discharge load capacitor; a switched capacitor digital-to-analog converter which is used for setting the discharge initial voltage of the discharge load capacitor; a buffer which is used for converting a voltage falling edge discharged by the discharge load capacitor into a rising edge and providing a stable output rising edge conversion rate; and a clock and control signalgeneration circuit which is used for receiving the input delay control word dcw and the input clock in and outputting an actual delay control word dcw _ act and a plurality of different clock phases.According to the invention, high linearity in a larger delay time range is realized, and the phase-locked loop has the characteristics of low noise and low power consumption, has high linearity, andis very suitable for being applied to a fractional-frequency phase-locked loop.

The invention relates to a method for limiting the maximum callable braking power of hydraulic brakes in automobiles. The heat generated by the hydraulic brakes is discharged through the coolant in the engine cooling cycle of the driving engine of the automobile. Drive the engine-driven coolant pump to circulate in the engine cooling cycle, with the following steps: pre-setting the adjustment intervention temperature; pre-setting the adjustment target temperature; detecting the coolant temperature continuously or at time intervals; if the coolant temperature rises to At or above the control intervention temperature, the maximum available braking power of the hydrodynamic brake is reduced with a predetermined gradient; the gradient of the reduction depends on the difference between the control target temperature and the control intervention temperature, the control intervention Both the temperature and the control target temperature are predefined as a function of the rotational speed of the vehicle's drive engine.

The invention discloses a radical benzene sulfonamide ethyl sulfuryl hydroxyethyl sulfate aniline compound and a preparation method thereof. The preparation method comprises the following steps: reacting acetanilide with chlorosulfonic acid and sulfoxide chloride to generate p-acetamido benzene sulfonyl chloride, and then condensing with sulfide generated through reaction between 2-chlorethamin hydrochloride and mercaptoethanol to obtain sulfur ether, re-oxidizing, etherifying or sulfonating the sulfur ether to obtain 2-[2-(4-amonibenzenesulfonamido)ethyl sulfuryl]hydroxyethyl sulfate or 2-[2-(4-amonibenzenesulfonamido)ethyl sulfuryl] hydroxyethyl sulfate-3-sulfonic acid. Comparing the active radical benzene sulfonamide ethyl sulfuryl hydroxyethyl sulfate aniline compound with 4-(2-sulfonylethanol sulfate)aniline; the synthesized reactive dye has bright colored light, and is low in substantivity, high in dye-uptake rate and fixation rate, less in hydrolysis dye, and excellent in various fastness indexes; especially, the light fastness, the soaping resistant fastness, and rubbing fastness are 0.5-1 level higher than ordinary variety.

The invention discloses a method for simultaneously measuring five corrosion removers in leather by adopting ultraperformance convergence chromatography, and belongs to the technical field of chemicalanalysis detection. The method comprises the steps of building a convergence chromatography technical program applicable to simultaneously detecting five corrosion removers including N-octyl isothiazolone, 2-(thiocyanic methyl sulfydryl)benzothiazole, 4-chloro-3-cresol, triclosan and o-phenylphenol in leather, a target compound is extracted, concentrated and filtered, qualitative and quantitativeanalysis is performed through the ultraperformance convergence chromatography, and the method is applicable to simultaneously measuring the five corrosion removers in leather shoes, leather productsand other leatherware. The method is high in sensitivity, good in stability, easy and rapid to operate, low in cost, environmentally friendly, and easy to apply and popularize.

The invention relates to an MEMS (micro-electromechanical system) variable capacitor with a linear C-V (capacitance-voltage) characteristic and a low-stress double-lever structure. The MEMS variable capacitor is characterized in that a lower polar plate, driving electrodes and anchor points are arranged on a dielectric substrate, two ends of an upper polar plate are fixedly supported on the anchor points by the aid of torsion beams, the middle of the upper polar plate corresponds to the lower polar plate, and the ends of the upper polar plate correspond to the driving electrodes; when linear additional voltages are exerted on the driving electrodes, the ends of the upper polar plate move downwardly, the middle of the upper polar plate moves upwardly, and a capacitance value between the upper polar plate and the lower polar plate is decreased; when the linear additional voltages stop being exerted on the driving electrodes, an initial horizontal state of the upper polar plate is restored via torsion elastic force of the torsion beams, the outer ends of the upper polar plate move downwardly to drive the upper polar plate to move upwardly, the distance from the upper polar plate to the lower polar plate is increased, and the capacitance value C is linearly decreased along with increase of a voltage value. The MEMS variable capacitor has the advantages that the initial distance from the upper polar plate to the lower polar plate is decreased owing to a stepped structure of the middle of the upper polar plate, so that an initial capacitance value is increased, the capacitance variation range is enlarged, and stress generated by deformation when the upper polar plate moves can be released advantageously.

The embodiment of the invention provides a battery management method and device and a vehicle. The battery management method comprises the steps of obtaining a battery state parameter of the electricvehicle; if the battery state parameter is between a first preset threshold value and a second preset threshold value, determining a first charging upper limit parameter corresponding to the first preset threshold value and a second charging upper limit parameter corresponding to the second preset threshold value; and determining a target charging upper limit parameter according to the first preset threshold value, the second preset threshold value, the first charging upper limit parameter and the second charging upper limit parameter. According to the technical scheme, the interval range where the target charging upper limit parameter is located is determined according to the interval range where the battery state parameter is located, and the target charging upper limit parameter is linearly reduced along with the increase of the battery state parameter in the corresponding interval range, so that a user does not perceive the endurance change of the whole vehicle; and different charging upper limit parameters can be set in each stage of the battery, so that the attenuation speed of the service life of the battery is reduced, and the safety risk is reduced.