Patents
Literature
Hiro is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
Hiro

138results about How to "Shorten off time" patented technology

Reverse conducting type insulated gate bipolar transistor without snapback effect

A reverse conducting type insulated gate bipolar transistor without a snapback effect belongs to the technical field of semiconductor power devices. A P floating region (7) is introduced between an N collector region (9) and an N buffer region (8) of a conventional RC-IGBT (Reverse Conducting-Insulated Gate Bipolar Transistor) so that the snapback effect of the reverse conducting type insulated gate bipolar transistor is eliminated, and the turn-off loss of the devices is reduced. The novel structure reduces the cellular length and the effective area of the N collector region (9) and increases the short-circuit resistance of a collector, the transmission efficiency of the P floating region (7) is higher than that of a P collector region (10), and the resistance of an N-drift region (6) is reduced through a conductance modulation effect, so that the snapback effect is eliminated. When the reverse conducting type insulated gate bipolar transistor reversely works, a parasitic transistor formed by the N-drift region (6), the P floating region (7) and the N collector region (9) is opened, so that a current path is provided, so as to form positive feedback of a PNPN (Positive-Negative-Positive-Negative) four-layer structure with the a P body region (5), the on-resistance when each device is reversely conducted is reduced, and the relatively low on-state voltage and the rapid shutdown are realized.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA +1

Reverse-conducting insulated-gate bipolar transistor (RC-IGBT) with P floating layer current bolt

The invention discloses a reverse-conducting insulated-gate bipolar transistor (RC-IGBT) with a P floating layer current bolt, and belongs to the field of semiconductor power elements. A medium buried layer is led in between an N collector region and a P collector region of a traditional RC-IGBT, and the P floating layer current bolt is led into an N-type buffering layer above the medium buried layer. According to the RC-IGBT with the P floating layer current bolt, other parameters of an element are not affected, break-over voltage of a snapback is obviously lowered, a reverse recovery soft factor is improved, current is distributed uniformly, local over-heating phenomenon is avoided, and the reliability of the RC-IGBT is improved.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA +1

Driving circuit of triode and driving method thereof

ActiveCN102957304ALow costPrevent deep saturationPower conversion systemsDriver circuitDc current
The invention relates to a driving circuit of a triode. The circuit comprises a current supply device, a first switch device, a second switch device, a switch control device, an inductor, a direct-current power supply and a current detection unit, wherein the current supply device is grounded after being sequentially connected with the first switch device and the second switch device; the triode is connected between the first switch device and the second switch device, the direct-current power supply is connected with the collecting electrode of the triode, and an emitting electrode of the triode is grounded; the switch control device receives a detection voltage provided by the current detection unit and an externally supplied control voltage to control the on-off states of the first switch device and the second switch device so as to control the on-off state of the triode; and the current supply device supplies a direct current which reflects the changing of the current of the collecting electrode to the base electrode of the triode. By utilizing the driving circuit of the triode, the turn-off time of the switch is shortened, and the power dissipation is reduced; and meanwhile, the invention discloses a driving method of the driving circuit of the triode and a switch power supply.
Owner:BYD SEMICON CO LTD

Insulated gate bipolar transistor

The invention provides an insulated gate bipolar transistor (IGBT), and relates to the field of integrated circuit manufacturing. The problem of tail currents when the IGBT is turned off can be solved. The IGBT comprises a cellular area which is placed on the front face, a terminal area which is surrounded the cellular area, an IGBT drift region of a first conduction type and an IGBT collector region which is placed on the back face. The IGBT collector region and the IGBT drift region are connected and placed below the IGBT drift region, wherein the IGBT drift region comprises a first drift region which is placed below the cellular area and a second drift region which is placed below the terminal area. The IGBT collector region comprises a heavy doping cellular collector region of a second conduction type and a non-conductive isolation area adjacent to the cellular collector region, wherein the cellular collector region is placed below the first drift region, the length of the non-conductive isolation area is smaller than or equal to the length of the terminal area, and the thickness of the non-conductive isolation area is greater than or equal to the thickness of the cellular collector region. Shutoff losses of the IGBT can be lowered, and the reliability of shutoff is improved.
Owner:HUAWEI TECH CO LTD

Tunnel IGBT with anode in short circuit

An anode-short tunnel pump IGBT belongs to the technical field of semiconductor power devices. With an anode-short structure and a tunnel pump structure simultaneously introduced into a traditional IGBT, or a tunnel pump structure into an anode-short IGBT, or an anode-short structure into a tunnel pump IGBT, the invention gives the advantages of both the anode-short IGBT and the tunnel pump IGBT to the anode-short tunnel pump IGBT so as to improve the turn-off characteristic of the device and lower the conductive voltage drop of the device. The invention can better reconcile the positive saturation voltage drop with the turn-off time, and optimize the conductive characteristic of the device, so that the invention is suitable in particular for application environments characterized by high voltage, heavy current and high frequency.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Bootstrapping sampling switch applied to high-speed and high-linearity analog-to-digital converter

The invention provides a bootstrapping sampling switch applied to a high-speed and high-linearity analog-to-digital converter. The bootstrapping sampling switch comprises a clock booster, a grid-source voltage follower, a conduction switch and a charging and discharging enhanced circuit, wherein several times of power voltage are generated by the clock booster and used for charging a capacitor; the grid-source voltage follower connects the capacitor between the grid and the source when the conduction switch is off, so that a relevantly constant grid-source voltage difference under different voltage input is ensured; the charging and discharging enhanced circuit is added in a charging or discharging loop during switching of the switch so as to shorten the off and on time, reduce a parasitic capacitance of the grid of the conduction switch and reduce the loss of the storage charge of the capacitor; the use of a high-voltage metal oxide semiconductor (MOS) tube is not needed; meanwhile, high-linearity sampling is realized (the sampling rate is more than 1 KMHz under 65-nano complementary metal-oxide-semiconductor (CMOS) technology and a stray-free dynamic range more than 95 decibels can be obtained). A complicated logic control circuit is absent in the structure, so the area of a chip cannot be increased; moreover, a requirement of the clock buffer is not needed to be enhanced.
Owner:BEIJING UNIV OF TECH

Twin-triode current control type self-oscillation flyback converter

The invention discloses a double triode current control self oscillation flyback converter which comprises a soft start part, a MOS tube TR1, a transformer T1, a pulse frequency modulating part, a benchmark amplifying part, an insulating optical coupler OC1 and a voltage regulation output loop part; an input electric quantity is connected with the output loop part by the transformer T1; wherein, the pulse frequency modulating part mainly comprises a triode TR2, a resistance R2, a capacitance C2 and a resistance R4; the base electrode of the triode TR2 is connected with the source electrode of the MOS tube TR1 by an bias resistance R3 and a capacitance C2 which are connected in parallel; the source electrode of the MOS tube TR1 is grounded by the resistance R4; the pulse frequency modulating part is additionally provided with an triode current control circuit; the triode current control circuit is connected between the MOS tube TR1 and the triode TR2 to realize the self oscillation output of the double triode current control at the input end. The converter of the invention has the advantages of high working efficiency and working with no load, which can ensure the output voltage to be stable, the powers for no load work and short circuit to be very low and realizes continuous short circuit protection and fast dynamic response.
Owner:MORNSUN GUANGZHOU SCI & TECH

Nuclear magnetic resonance and transient electromagnetic combination instrument and work method

The invention relates to a nuclear magnetic resonance and transient electromagnetic combination instrument and a work method. According to the nuclear magnetic resonance and transient electromagnetic combination instrument, a computer is connected with an SQUID sensor through a signal collection card and a signal conditioning circuit, the computer is connected with a 24V storage battery through an MCU, a CPLD signal generation module and a power module, the power module is connected with the signal conditioning circuit through an emitting circuit and an optocoupler, the CPLD signal generation module is connected with an energy quick consumption circuit through the emitting circuit and an emitting coil, and the MCU is connected with an E2PROM, the optocoupler and the signal conditioning circuit. The work method comprises the steps that a transient electromagnetic detection mode is selected, the SQUID sensor is used for receiving transient electromagnetic signals, and measuring point apparent resistivity distribution is obtained; a nuclear magnetic resonance detection mode is executed in a switched mode, the SQUID sensor is used for receiving nuclear magnetic resonance signals, and measuring point contained underground water distribution is obtained. The apparent resistivity distribution and the underground water distribution are detected by one set of equipment, the advantages of two instruments are achieved, the SQUID sensor is adopted to improve detection precision, the signal-to-noise ratio of the received signals is effectively improved, and meanwhile the problem that a receiving coil is inconvenient to carry outdoors is solved.
Owner:JILIN UNIV

Grooved gate short circuit anode SOI LIGBT

The invention belongs to the technical field of power semiconductors and relates to a grooved gate short circuit anode SOI LIGBT. In comparison with the traditional short circuit anode LIGBT, anode grooves connected to anode potential are introduced at an anode end, and a P body area is introduced right below an N+ anode area; and grooved gates and cathode grooves connected with a cathode are introduced in a cathode area. When the device is turned off, the anode groove is connected to high potential, an NMOS in the anode area is started automatically, extraction of electrons stored in a driftarea is quickened, and the turn-off time and the turn-off energy loss are reduced; when the device is in a high-voltage high-current state, the cathode groove forms a hole bypass, and happening of latch-up effects is suppressed; when the device is conducted, under blocking of an electronic barrier in the P body area, electron current in the drift region is not easy to be collected by the N+ anode,voltage reentry effects are eliminated, and as the grooved gate structures of the cathode are in parallel connection, the channel density is increased and the conduction voltage drop is reduced. Thegrooved gate short circuit anode SOI LIGBT has the beneficial effects that in comparison with the traditional short circuit anode LIGBT, a voltage reentry phenomenon is eliminated under a smaller transverse cell size, and the conduction voltage drop is lower.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Half-bridge driving circuit

InactiveCN103683872AAccelerate the discharge speed of the control terminalReduce power consumptionPower conversion systemsElectricityControl signal
The invention discloses a half-bridge driving circuit which comprises a bootstrap circuit and a half-bridge circuit, and further comprises a first switch circuit, a second switch circuit, a first discharge circuit and a second discharge circuit, wherein the bootstrap circuit comprises a diode and a capacitor; the first switch circuit is powered on when a first control signal is in high level and is powered off in low level; the second switch circuit is powered on when a second control signal is in low level and is powered off in high level; the first discharge circuit is powered off when the first switch circuit is powered on and is powered on when the first switch circuit is powered off; the second discharge circuit is powered on when the second control signal is in high level and is powered off in low level; the on / off states of the two switch circuits are changed by changing the input control signals so as to control the on / off of upper and lower bridges; when the first discharge circuit is powered on, a control end of the upper bridge can be controlled to discharge electricity so as to accelerate the upper bridge to be closed; when the second discharge circuit is powered on, a control end of the lower bridge can be controlled to discharge electricity so as to accelerate the lower bridge to be closed. The electricity discharge speeds of the control ends of the upper bridge and the lower bridge are respectively accelerated through the first discharge circuit and the second discharge circuit.
Owner:SHENZHEN OCEANS KING LIGHTING ENG CO LTD +1

Fluidized-bed polymerization method and polymerization reactor

InactiveCN1438249AImproved dwell time distributionReduced dynamic reaction volumeFluidized bedProduct gas
The invention discloses a fluid bed polymerizaing method and the reactor. Polymerized monomer, copolymerized monomer, molecular-weight adjusting gas, nitrogen gas, condensate, catalyzer as well as aid-catalyzer enter in the reactor to make polymerization, part of gas stream from the top of the reactor circulates by compressor and is cooled to liquefacient temperature by heat exchanger, the obtained two streams enter in A and B areas of the reactor; the two streams return to the reactor in gas-liquid mode, and the liquid is separated out and directly leaded into the fluid bed; the polymerization: temperature 70-130 deg.C, pressure 1-10 MPa.
Owner:CHINA PETROLEUM & CHEM CORP +1

High-speed large-current power field-effect transistor driving circuit

The invention discloses a high-speed large-current power field-effect transistor driving circuit, which comprises a driving pre-circuit, a totem-pole circuit, and a driving post-circuit, wherein the driving pre-circuit comprises a capacitor C1, resistors R1, R2 and R3, a diode D1 and triodes T1 and T2; the totem-pole circuit consists of diodes D2 and D3, resistors R4 to R11, a capacitor C2 and field-effect transistors Q1 and Q2; the driving post-circuit consists of resistors R12 and R13, diodes D4 and D5, a capacitor C3 and a field-effect transistor Q3; the driving pre-circuit is connected with a driving signal Vg, the driving post-circuit is connected with a driving object Q3, and the totem-pole circuit is connected with the driving pre-circuit and the driving post-circuit. The driving circuit is simple in structure, low in cost, large in output current and high in load-carrying capacity, and can meet the requirement on the high-speed low-voltage large-current driving on the field-effect transistors under specific situations.
Owner:WUXI YANAO ELECTRONICS TECH

Short-circuit shutoff method for insulated gate bipolar transistor (IGBT) of high-power current transformer

The invention discloses a short-circuit shutoff method for an insulated gate bipolar transistor (IGBT) of a high-power current transformer, which is applied in the fields of wind power current transformers and current transformers for ships and the like. The shutoff method for a bypass switch of the conventional short-circuit soft shutoff technique is improved, a detection circuit in a gate voltage discharge process is increased for detecting the gate voltage during discharging, and the bypass switch is actuated to enter the soft shutoff process after the preliminary discharge process of the gate voltage is finished. The method overcomes the defect of long shutoff time delay of the conventional soft shutoff technique, reduces the delay time of the conventional short-circuit soft shutoff during discharging, shortens the operating time of the soft shutoff operation, and increases the survival rate of the IGBT in the short-circuit process.
Owner:乌云翔

Resonant gate driving circuit suitable for high-frequency application

The invention discloses a resonant gate driving circuit suitable for a high-frequency application. The resonant gate driving circuit comprises a resonant capacitor Cr, a resonant inductor Lr, an auxiliary switching tube 1, an auxiliary switching tube 2, a main switching tube 1, a main switching tube 2 and a main power device Q1. The resonant capacitor Cr is connected in series with the resonant inductor Lr, the resonant inductor Lr is connected to a source electrode of the auxiliary switching tube 1, a drain electrode of the auxiliary switching tube 1 is connected to a drain electrode of the auxiliary switching tube 2, a source electrode of the auxiliary switching tube 2 is connected to a source electrode of the main switching tube 1, a drain electrode of the main switching tube 2 and a gate of the main power device Q1, a drain electrode of the main switching tube 1 is connected to a positive power supply voltage VCC, and a source electrode of the main switching tube 2 is connected tonegative power supply voltage VEE. According to the driving circuit of the invention, the resonant capacitor Cr, the resonant inductor Lr and the four switching tubes S1, S2, S3 and S4 are used to achieve gate resonant driving, the driving circuit can recover gate driving power, the driving circuit loss is reduced, and the switch-on and switch-off times of the main power device are shortened.
Owner:SOUTHEAST UNIV +1

IGBT device capable of improving switch-on and switch-off speed and switch-on and switch-off uniformity and manufacturing method thereof

The invention relates to a power device and a manufacturing method of the power device, in particular to an IGBT device capable of improving the switch-on and switch-off speed and switch-on and switch-off uniformity and a manufacturing method of the IGBT device. The IGBT device comprises emitting electrode PAD regions, a grid PAD region, grid Finger regions, a grid Bus region and a terminal region. The grid PAD region is located at the center of the device, the emitting electrode PAD regions are distributed around the grid PAD region and separated by the grid Finger regions, the grid Bus region surrounds the emitting electrode PAD regions, and the terminal region is located on the periphery of the grid Bus region. By improving the traditional structural design of a polycrystalline silicon layer and a metal layer, the speed of charging and discharging cellular grids is improved when the IGBT device is switched on or switched off, and accordingly the overall switch-on and switch-off speed of the IGBT device is improved. Compared with a traditional IGBT device structure, the IGBT device has the advantages that the switch-on and switch-off speed of the IGBT device is improved, and the switch-on and switch-off uniformity of IGBT cells is improved at the same time.
Owner:STATE GRID CORP OF CHINA +2

MOS grid-control thyristor

InactiveCN103956381AImprove short-circuit safe working abilityShorten off timeThyristorAnode voltageElectron flow
The invention relates to the semiconductor technology, in particular to an MOS grid-control thyristor. A P+ cathode contact area 10 is modified, the width of the P+ cathode contact area 10 is increased, the metallurgical junction form is changed, and the conveying passage of electrons flowing from cathode metal 11 is shortened. The forward direction work characteristic of a device is controlled by a JFET composed of the P+ cathode contact area 10 and an N-trap 9, a channel pinch-off effect can occur under a relatively small anode voltage, the intensity of saturation current of the device can be controlled, and optimization valuing can be carried on the junction depth and width of the P+ cathode contact area 10 according to the design requirements of the device. The MOS grid-control thyristor is particularly suitable for the MOS grid-control thyristor.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Shifting register, grid driving circuit, array substrate and display device

The invention discloses a shifting register, a grid driving circuit, an array substrate and a display device. The shifting register comprises an input module and an output module and further comprises a grid signal generating module which is connected with the input module and the output module, wherein the input module comprises a first clock signal input end, a second clock signal input end, a third clock signal input end and a fourth clock signal input end, signals the same in phase and amplitude are input in the third clock signal input end and the second clock signal input end, and direct-current voltage signals are input in the fourth clock signal input end; the shifting register furthermore comprises a control module connected with the grid signal generating module, the control module comprises a seventh thin film transistor, a second capacitor and an eleventh thin film transistor, the third clock signal input end is connected with a grid of the seventh thin film transistor and a first end of the second capacitor, the fourth clock signal input end is connected with a source electrode of the eleventh thin film transistor, and the level of the point is a first level. Two sequence signals are added, in this way, discharging at the output ends is accelerated, and turn-off time of grid signals is shortened.
Owner:HEFEI BOE OPTOELECTRONICS TECH +1

Driving circuit of Cascode type GaN power device

The invention relates to a driving circuit of a Cascode type GaN power device. A turn-on loop and a turn-off loop of the GaN driving circuit are separated, and a turn-on acceleration capacitor and a turn-off acceleration capacitor with different capacitance values are adopted in the turn-on loop and the turn-off loop respectively to connect a turn-on gate resistor and a turn-off gate resistor in parallel, so that different dynamic and steady grid currents are provided for the GaN power device, the turn-on and turn-off processes are accelerated, the turn-on and turn-off time is shortened, and meanwhile, the peak and oscillation of voltage and current are reduced; the voltage peak, the current peak, the oscillation, the turn-on time and the turn-off time of the GaN power device in the switching process are reduced, and the requirements for high reliability, small loss and high switching speed of the GaN driving circuit are met. According to the invention, the performance requirement of the GaN power device under a high-frequency condition can be met, high switching speed and low switching loss are ensured, meanwhile, voltage and current peaks and oscillation of the drain and source electrodes in the switching-on and switching-off processes of the GaN power device can be effectively suppressed, and high-reliability work of the GaN power device is ensured.
Owner:NORTHWESTERN POLYTECHNICAL UNIV

Insulated gate bipolar translator (IGBT) device with two short-circuit positive electrodes

The invention discloses an insulated gate bipolar translator (IGBT) device with two short-circuit positive electrodes, and belongs to the technical field of semiconductor power devices. A positive electrode structure of the device is a two-positive-electrode short-circuit structure. The IGBT device comprises a first P+ hole emission layer, a second P+ hole emission layer, a metal collector and a silicon dioxide barrier layer, wherein the silicon dioxide barrier layer is positioned on the back face of the first P+ hole emission layer; the metal collector is positioned on the side face of the first P+ hole emission layer and below the second P+ hole emission layer, and the two P+ hole emission layers are contacted with each other; the second P+ hole emission layer is positioned at the bottom of an N- drift region and staggered in parallel with the first P+ hole emission layer; and an electronic trench is formed between the first P+ hole emission layer and the second P+ hole emission layer. The positive electrode structure of the IGBT device is improved, so that the hole injection efficiency is improved, the current carrier concentration distribution in the drift region is optimized, the conductivity modulation performance in the device body is improved, a negative differential resistance (NDR) region is eliminated effectively, the cut-off loss of the IGBT device is reduced effectively, and finally, compromise optimization for conductivity pressure drop and cut-off loss is realized.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA +1

Control device and method for power factor correction converter

The invention discloses a control device and method for a power factor correction converter. The control device comprises a PID control unit, an off-time adjustment unit, an on-time adjustment unit and a switching frequency control unit, wherein the PID control unit is used for outputting a control signal Vm based on an output voltage of the power factor correction converter, the off-time adjustment unit is used for outputting an off-time adjustment signal of a power switch tube of the power factor correction converter based on the PID control signal Vm, the on-time adjustment unit is used foroutputting an on-time adjustment signal based on an input voltage Vin of the power factor correction converter, the control signal Vm and a power switch tube current sampling signal, and the switching frequency control unit is used for adjusting the switching frequency of the power switch tube based on the off-time adjustment signal and the on-time adjustment signal.
Owner:DELTA ELECTRONICS DONGGUAN

Silicon on insulator-lateral insulated gate bipolar transistor (SOI-LIGBT) device structure with low switch-off loss and dual groove gates

The invention provides a silicon on insulator-lateral insulated gate bipolar transistor (SOI-LIGBT) device structure with low switch-off loss and dual groove gates. The SOI-LIGBT device structure comprises a P-type substrate, buried oxide layer SiO2, an N-type drift region, a P-type well region, an N-buffer layer, an oxide layer, two N-type source ends, a P-type contact region and an N-type positive electrode region, wherein the P-type contact region is arranged between the two N-type source ends, gate oxide layers are arranged at two sides of a channel between the source ends and the P-type well region, and poly-silicon is arranged aside the gate oxide layers and is arranged at two sides of the P-type well region and at a left side of the N-buffer layer. The SOI-LIGBT device structure possesses a dual-gate structure and has higher current capability under the same condition, holes directly injected to the P-type well region are reduced by the introduction of an N-type carrier storage layer, so that the carrier distribution is more uniform, the carrier combination during switch off is facilitated, and the switch-off time is reduced; the effective space of the N-type drift region is reduced by groove medium SiO2, the injection of carriers at a right side is also simultaneously blocked, and a carrier accumulation layer is formed; and based on two effects, the switch-off loss of the structure is substantially reduced.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA +1

Novel array type transient electromagnetic detection system and detection method

The invention relates to the technical field of transient electromagnetic underground detection, in particular to a novel array type transient electromagnetic detection system and a detection method.The system comprises a transmitting circuit, a receiving circuit and an industrial computer; the transmitting circuit comprises four transmitting coils arranged in an array, four transmitting coils equally distributing flow directions and a current sharing controller which ensures the same current waveform and amplitude of the four transmitting coils; the receiving circuit includes a receiving coil which is placed on a geometric center of a transmitting coil array and receives a secondary field generated by an excitation magnetic field of the four array type transmitting coils; the industrialcomputer is used for controlling the emission current of the transmitting circuit and controlling the transmitting circuit to evenly distribute the current flowing to the four transmitting coils according to the collected emission current to ensure that the current waveform and the amplitude are consistent. An array type emission method effectively solves the contradiction between the excitation depth and the coil diameter, utilizes the superposition of a plurality of small coils to provide a stronger and more uniform excitation primary field, and is beneficial to improving the quality of a detection signal.
Owner:JILIN UNIV

A bipolar power semiconductor device and a preparation method thereof

The invention relates to a bipolar power semiconductor device and a preparation method thereof, belonging to the technical field of semiconductor power devices. When the cathode structure of the conventional bipolar power semiconductor device is kept unchanged, by introducing an anode trench gate structure and a source region and / or a base region into the anode region of the device, the forward conduction voltage drop of the anode diode is bypassed by controlling the anode trench gate structure without affecting the normal operation and opening of the device, so that the effect of reducing theforward conduction voltage drop of the power semiconductor device is achieved. After the anode diode is bypassed, the minority carrier injection from the anode region to the drift region decreases, and the reverse recovery time of the device is shortened when the device is turned off, which improves the turn-off speed of the device and reduces the switching loss. The invention improves the carrier concentration distribution of the whole N-type drift region and the compromise between the positive conduction voltage drop and the switching loss. Moreover, the fabrication method of the device does not require additional process steps, and is compatible with the traditional device fabrication method.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Power on delay circuit and method

The invention provides a power on delay circuit and method; the delay circuit comprises a first switch tube, a second switch tube, a first capacitor and a first resistor; the source electrode of the first switch tube is connected with a power supply; the first capacitor is connected between the grid electrode and the source electrode of the first switch tube; the grid electrode of the second switch tube is connected with the drain electrode of the first switch tube; the drain electrode and the source electrode of the second switch tube are connected with a conversion circuit of the output voltage of a pixel close signal; the first resistor is connected between the grounding end and the grid electrode of the first switch, and connected in series with the first capacitor; the power supply charges the first capacitor through the first resistor; the first and second switch tubes are conducted in order when the capacitor is charged, and the absolute value of the output voltage of the pixel close signal rises when the capacitor is charged. By using the method and circuit, the pixel quantity of light is weak when a black matrix charges the capacitor in the pixel in a start up process, and the quantity of light can be even reduced to a human eye undistinguishable level, so a user cannot notice the display panel whitening phenomenon.
Owner:BOE TECH GRP CO LTD +1

Optical module and optical signal output control method

Embodiments of the invention provide an optical module and an optical signal output control method. The optical module comprises a laser source, a semiconductor laser amplifier, and a drive circuit of the semiconductor laser amplifier. The optical module further comprises a switching circuit of which one end is connected with the bias current output end of the drive circuit of the semiconductor laser amplifier, and a controller which is used for making the switching circuit connect the bias current output end of the drive circuit to the semiconductor laser amplifier after receiving an optical signal transmission instruction, and making the switching circuit disconnect the bias current output end of the drive circuit from the semiconductor laser amplifier after receiving an optical signal stop instruction. According to the technical scheme of the invention, the on time and off time of optical signal output of the optical module can be shortened greatly, and quick start and cutoff of optical signal output of the optical module is realized.
Owner:HISENSE BROADBAND MULTIMEDIA TECH

Circuit arrangement and method for operation of discharge lamp

The present invention relates to a circuit arrangement for operation of a discharge lamp, comprising: an input having a first input connection (E1) and a second input connection (E2) for connection of a supply voltage; a first electronic switch (Q1), which has a control electrode, a working electrode and a reference electrode, wherein the working electrode is coupled to the first input connection (E1); a first diode (D1), the anode of which is coupled to the second input (E2) and the cathode of which is coupled to the reference electrode of the first electronic switch (Q1) to form a first junction point (N); a control apparatus (12), which is coupled to the control electrode of the first electronic switch (Q1) in order to drive said first electronic switch (Q1); an output with a first output connection (A1) and a second output connection (A2) for providing an output voltage (UA) to the discharge lamp (La); an inductance (Lz), which is arranged in series with one of the output connections (A1; A2); a lamp inductor (L1), which is coupled between the first junction point (N) and the first output connection (A1); and a first capacitor (C1), which is coupled between the first output connection (A1) and the anode of the first diode (D1); wherein the control apparatus (12) is designed to switch the first electronic switch (Q1) on continuously for a switched-on time and to switch it off continuously for a switched-off time; wherein the circuit arrangement furthermore comprises a voltage measurement apparatus (10) for measuring the output voltage (UA), wherein the voltage measurement apparatus (10) is designed to produce at its output a signal which is correlated with the measured output voltage (UA) wherein the voltage measurement apparatus (10) is coupled to the control apparatus (12) in order to transmit this signal to the control apparatus (12), and wherein the control apparatus (12) is designed to vary the switched-off time (Toff) as a function of the measured output.
Owner:OSRAM GMBH

SA-LIGBT device with grid-controlled collector

ActiveCN110504307AControl short circuit resistanceEliminate the snapback effectSemiconductor/solid-state device manufacturingSemiconductor devicesElectron blocking layerTransmitter
The invention relates to an SA-LIGBT device with a grid-controlled collector, and belongs to the field of electronic devices. The device comprises a transmitter, a grid, an N-type drift area and a grid-controlled collector area from the left to right. The grid-controlled collector area comprises an N-buffer I buffer layer, a P-collector, an N-buffer II buffer layer, a P-type electron barrier layerP-base and an N-collector from the left to right. A transverse grooved grid is arranged under the P-type electron barrier layer P-base and the N-collector. When in forward conduction, the P-type electron barrier layer P-base can stop electrons from flowing to the N-collector, and the short-circuit resistance of the collector is increased. Through adjusting the length and concentration of the P-type electron barrier layer P-base, the short-circuit resistance of the collector can be adjusted, and the snapback effect can be eliminated. When being turned off, the P-type electron barrier layer canbe transformed to the N-type under the grid-controlled voltage, the electron channel is formed, the carrier extraction efficiency is improved, and thus the off time of the device is effectively reduced.
Owner:CHONGQING UNIV OF POSTS & TELECOMM

A lateral bipolar power semiconductor device and a manufacturing method thereof

A lateral bipolar semiconductor power device and a preparation method thereof belong to the technical field of semiconductor power device. When the cathode structure of the conventional bipolar powersemiconductor device is kept unchanged, by introducing an anode trench gate structure and a source region and / or a base region into the anode region of the device, the forward conduction voltage dropof the anode diode is bypassed by controlling the anode trench gate structure without affecting the normal operation and opening of the device, so that the effect of reducing the forward conduction voltage drop of the power semiconductor device is achieved. After the anode diode is bypassed, the minority carrier injection from the anode region to the drift region decreases, and the reverse recovery time of the device is shortened when the device is turned off, which improves the turn-off speed of the device and reduces the switching loss. The invention improves the carrier concentration distribution of the whole N-type drift region and the compromise between the positive conduction voltage drop and the switching loss. Moreover, the fabrication method of the device does not require additional process steps, and is compatible with the traditional device fabrication method.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Rapid turning-off silicon-on-insulator-lateral insulated gate bipolar transistor

A fast turn-off silicon-on-insulator lateral insulated gate bipolar transistor device, the semiconductor has: a buried oxygen on a P-type substrate, an N-type drift region on the buried layer, a P-type well region and a N-type buffer area, in the N-type buffer area, there is a heavily doped P-type collector region, in the P-type well region, there are heavily doped P-type emitter regions and N-type emitter regions, in the P-type well region There is a gate oxide layer on the surface, and a polysilicon layer on it. In the heavily doped P-type emitter region, there is a first vertical groove that is as deep as the buried oxygen. A lateral trench extending to the drift region, a second vertical trench is provided in the heavily doped P-type collector region and its depth is as deep as buried oxygen, and the above-mentioned trench partially expands inward to form second transverse trenches with equal spacing The groove extends to the drift region, and all the above grooves are filled with polysilicon wrapped with a pressure-resistant medium, and the filler located in the drift region is a pressure-resistant medium.
Owner:SOUTHEAST UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Eureka Blog
Learn More
PatSnap group products