32results about How to "Good constant current characteristics" patented technology

The invention relates to a high-efficiency LED constant current driving circuit. The circuit comprises an input rectification filter circuit, a switch power supply management chip, an isolation switch transformer, a primary clamping circuit of the transformer, an output rectification filter circuit, an output current sampling circuit, a reference voltage generation circuit, a comparison circuit and a photoelectrical coupling circuit, wherein the input end of the input rectification filter circuit is connected with commercial AC electricity, while the output end is connected with a primary winding of the isolation switch transformer through the switch power supply management chip; the primary clamping circuit of the transformer is connected in parallel with the primary winding of the isolation switch transformer; the input end of the output rectification filter circuit is connected with the primary winding of the isolation switch transformer, while the output end is connected with LED load; an output current sampling circuit is connected in series with the LED load; the input end of the reference voltage generation circuit is connected with the LED load; and the input end of the comparison circuit is connected with the output current sampling circuit and the reference voltage generation circuit, while the output end is connected with the switch power supply management chip through the photoelectrical coupling circuit. The circuit improves the circuit integration degree, the reliability, the constant current precision and the circuit conversion efficiency.

The invention provides a DC small current constant-current source and a method for adjusting the constant-current source and aims at solving the problem of the noise of the output current caused by the noise of an amplifier in a feedback circuit of the existing DC small current source. The DC small current constant-current source comprises a voltage source, a differential amplification circuit, a V / I conversion circuit, a current output terminal and a feedback circuit; the voltage source is connected in series with the differential amplification circuit and outputs voltage to the differential amplification circuit; the differential amplification circuit is connected in series with the V / I conversion circuit; the V / I conversion circuit generates the current and outputs the current by the current output terminal; the feedback circuit comprises a sampling circuit and a filter circuit which are connected in series; after sampling at the output current terminal of the V / I conversion circuit, the sampling circuit outputs the voltage signal which is fed back and filtrated by the filter circuit to the input terminal of the differential amplification circuit. Meanwhile, the output voltage of a feedback branch is taken as the following output voltage of the current output terminal. The invention can provide the DC small current with high precision.

The invention discloses a two-end constant current device, comprising a first depletion type transistor and a resistor, wherein the source electrode of the first depletion type transistor is connected with a first end of the resistor, the grid electrode of the first depletion type transistor is connected with a second end of the resistor, and the first depletion type transistor is a gallium nitride depletion type transistor. The constant current effect of the two-end constant current device is realized by the negative feedback effect of the resistor, and the two-end constant current device has the advantages of high response speed, high breakdown voltage, high temperature resistance, good constant-current characteristic and high temperature stability by using the gallium nitride transistor characteristics of being high in response speed, being capable of bearing higher withstand voltage and being affected slightly by temperature.

The invention discloses a control circuit and method for a switching power converter. The switching power converter comprises a power conversion circuit, a sampling resistor and a switching power controller. Output currents are provided for the switching power converter through the power conversion circuit. The switching power controller comprises a power switch, an error amplifier, a comparator circuit and a logic and drive circuit. The power switch is used for controlling power supply of the power conversion circuit, and the sampling resistor is coupled to the power switch and provides sampling voltage signals. The error amplifier is used for receiving the output current equivalent value and the preset threshold value of the switching power converter so as to generate error voltages, wherein the output current equivalent value indicates the amplitude of the output currents of the switching power converter. The comparator circuit is used for comparing the sampling voltage signals and the error voltages and generating comparison output signals. The logic and drive circuit is used for generating drive signals, wherein when the comparison output signals generated by the comparator circuit indicate that the sampling voltage signals excess the error voltages, the drive signals switch off the power switch.

The invention relates to an inductive energy-storage microsecond-grade high-power pulse current source comprising an inductive charging circuit, an inductive discharging circuit and a clamping circuit, wherein the inductive charging circuit is a series loop which consists of an excitation power supply V2, an inductor L and a switch tube; the inductive discharging circuit is a series loop which consists of a loader, a fly-wheel diode D1 and the inductor L; and the clamping circuit is connected with the inductive charging circuit in a spanning way. The invention can generate a current-controllable high-power pulse power supply on the negative-resistance loader, has adjustable striking voltage, not only has very well constant-current characteristics, but also can fast respond to plasma arcs and realize the ultrafast switching of striking arcs and constant currents.

The invention relates to semiconductor technologies, in particular to a vertical current regulative diode and a manufacturing method thereof. The vertical current regulative diode comprises an oxide layer, a highly-doped N-type epitaxial layer, a lightly-doped N-type epitaxial layer, a heavily-doped N+ substrate and a metal anode which are sequentially arranged in a stacked mode. The vertical current regulative diode is characterized in that a resistor is additionally arranged to serve as a negative feedback structure. The vertical current regulative diode has the advantages that because the introduced resistor has a certain voltage drop when a device works, a channel can be pinched off more easily, the vertical current regulative diode can enter a constant current area rapidly, the breakdown voltage of the lateral current regulative diode is effectively increased, the lateral current regulative diode has a low pinch-off voltage, the constant current of the lateral current regulative diode is effectively increased, and the effective operating voltage range of the lateral current regulative diode is effectively widened. The method is especially suitable for the lateral current regulative diode.

The invention provides a low-power-consumption and low-delay current comparator based on Wilson current sources, and a circuit module. The low-power-consumption and low-delay current comparator basedon the Wilson current sources comprises a first Wilson current source and a second Wilson current source serving as an input stage, a differential amplifier serving as an intermediate stage, and an output gain stage serving as an output stage, wherein a first input current and a second input current, which serve as comparison objects, are respectively input into the first Wilson current source anda second Wilson current source; an output end of the first Wilson current source and an output end of the second Wilson current source are respectively connected to two input ends of the differentialamplifier; and an output end of the differential amplifier is connected to the output gain stage. A current structure provided by the invention has the advantages of high comparison precision and a low-delay propagation characteristic.

The invention relates to an infrared gesture recognition device and a recognition method. The infrared gesture recognition device comprises an infrared receiving tube, an infrared compensation tube, adriving module, a control module and a plurality of infrared emission tubes which are integrated on a PCB, wherein the infrared receiving tube, the infrared emission tubes and the infrared compensation tube are respectively arranged on the back of the PCB; open holes are formed in positions corresponding to the infrared receiving tube and the infrared emission tubes on the PCB and are used for emitting and receiving infrared ray from the front of the PCB; the infrared compensation tube is used for emitting infrared ray into the PCB. Compared with the prior art, infrared emission units and aninfrared compensation unit of the device adopt proportional circuits based on mirror current sources, so that the current in the device has certain self-regulation capability and good constant-currentcharacteristic, and the device has high temperature stability; meanwhile, compared with the prior art, the device is capable of removing the interference of the background environment light and solves the disadvantage that the infrared gesture module is influenced by the environment light at present; the reliability and the stability are improved.

The invention relates to a semiconductor technology, and particularly to a constant-current JFET (Junction Field Effect Transistor) device and a manufacturing method thereof. The constant-current JFET device is characterized in that the junction depths of a P+ surface grid electrode region 5 and a P+ back grid electrode region 2 are un-uniform; the junction depth of the P+ surface grid electrode region 5 from one end near an N+ drain electrode region 6 to one end ear an N+ source electrode region 7 is increased gradually; the junction depth of the P+ back grid electrode region 2 from one end near the N+ drain electrode region 6 to one end near the N+ source electrode region 7 is increased gradually. The constant-current JFET device has the beneficial effects of being relatively good in constant-current characteristic and capable of meeting the demand on smaller constant-current precision. The invention is particularly suitable for the constant-current JFET device and the manufacturing thereof.

The invention relates to a multipath current-sharing output LED (Light-Emitting Diode) driving power supply and a dimming method. The driving power supply comprises a switching network module, an LCL-nT type resonance network, a rectification network and a load unit, which are orderly connected with each other; the switching network comprises a first bridge arm and a second bridge arm which are connected in parallel, wherein the second bridge arm is used as a phase shift bridge arm and used for realizing wide-range lighting control; and the load unit comprises n paths of current-sharing output LED loads. The multipath current-sharing output LED driving power supply and the dimming method provided by the invention can realize constant and balanced output current under multiple paths of different LED lamp voltages, and have the characteristics of being simple in circuit structure, good in constant-current characteristic and high in current sharing accuracy, etc.

The invention discloses an LED drive device and a control circuit and a control method of the LED drive device. The control circuit of the LED drive device comprises a conduction time control circuit, an average current value obtaining circuit, a proportion superposition circuit, a comparison circuit, an OR gate, a set signal generation circuit and an RS trigger, wherein the conduction time control circuit is used for generating a first control signal according to a sawtooth wave signal and first reference voltage; the average current value obtaining circuit is used for generating an average current signal of reflecting an average output current value according to a current sampling signal; the proportion superposition circuit is used for superposing the average current signal and the sawtooth wave signal according to the ratio to generate a superposed signal; the comparison circuit is used for comparing the superposed signal with second reference voltage to generate a second control signal; the OR gate is used for generating a set signal according to the first control signal and the second control signal; the set signal generation circuit is used for generating the set signal; and the RS trigger is used for generating a switching control signal according to a reset signal and the set signal. By the control circuit of the LED drive device, a compensation network of a regulating ring can be omitted; a relatively high power factor is achieved; and a leakage circuit is not needed when applied to dimming of a silicon controlled rectifier.

The invention relates to semiconductor technology, particularly a JFET (junction field-effect transistor) device and a manufacturing method thereof. A current shallow groove auxiliary layer (13) and a voltage shallow groove auxiliary layer (14) are introduced into the ditch of the JFET device; the current shallow groove auxiliary layer (13) and voltage shallow groove auxiliary layer (14) are positioned on both ends of a P+ gate region (1) and connected with the P+ gate region (1); the current shallow groove auxiliary layer (13) is utilized to reduce the ditch modulation effect, thereby implementing small variable rate of output current within wide voltage input range; and the combined action of the voltage shallow groove auxiliary layer (14) and current shallow groove auxiliary layer (13) is utilized to reduce the curvature effect, thereby enhancing the voltage resistance of the device. The device has favorable constant-current characteristic on the basis of uncomplex manufacturing technique, has small variable rate within wide voltage input range, can satisfy the demand for lower constant-current precision, and is especially suitable for low-power LED (light-emitting diode) lamp constant-current drive. The method is especially suitable for low-power LED lamp constant-current JFET devices.

The invention relates to a high-efficiency LED constant current driving circuit. The circuit comprises an input rectification filter circuit, a switch power supply management chip, an isolation switch transformer, a primary clamping circuit of the transformer, an output rectification filter circuit, an output current sampling circuit, a reference voltage generation circuit, a comparison circuit and a photoelectrical coupling circuit, wherein the input end of the input rectification filter circuit is connected with commercial AC electricity, while the output end is connected with a primary winding of the isolation switch transformer through the switch power supply management chip; the primary clamping circuit of the transformer is connected in parallel with the primary winding of the isolation switch transformer; the input end of the output rectification filter circuit is connected with the primary winding of the isolation switch transformer, while the output end is connected with LED load; an output current sampling circuit is connected in series with the LED load; the input end of the reference voltage generation circuit is connected with the LED load; and the input end of the comparison circuit is connected with the output current sampling circuit and the reference voltage generation circuit, while the output end is connected with the switch power supply management chip through the photoelectrical coupling circuit. The circuit improves the circuit integration degree, the reliability, the constant current precision and the circuit conversion efficiency.

The invention discloses a constant-current driven LED projection lamp which comprises a bottom shell, a surface cover, an LED light source assembly and an LED driver, wherein the LED light source assembly is mounted in a light source mounting slot; the LED driver is mounted in a drive mounting slot; the LED driver and the LED light source assembly are independently mounted relative to each other, so that the LED driver is conveniently replaced and maintained; and a primary side feedback type LED constant-current drive circuit is arranged in the LED driver, and the circuit is simple and can output constant current. The LED light source assembly comprises an SMD light source and a light reflector; a plurality of light reflecting cups which are in one-to-one correspondence to LED chips are arranged on the light reflector; and each light reflecting cup independently distributes light for each LED chip. The constant-current driven LED projection lamp improves light outlet efficiency, so that light spots are more uniform.

The invention provides a DC small current constant-current source and a method for adjusting the constant-current source and aims at solving the problem of the noise of the output current caused by the noise of an amplifier in a feedback circuit of the existing DC small current source. The DC small current constant-current source comprises a voltage source, a differential amplification circuit, aV / I conversion circuit, a current output terminal and a feedback circuit; the voltage source is connected in series with the differential amplification circuit and outputs voltage to the differentialamplification circuit; the differential amplification circuit is connected in series with the V / I conversion circuit; the V / I conversion circuit generates the current and outputs the current by the current output terminal; the feedback circuit comprises a sampling circuit and a filter circuit which are connected in series; after sampling at the output current terminal of the V / I conversion circuit, the sampling circuit outputs the voltage signal which is fed back and filtrated by the filter circuit to the input terminal of the differential amplification circuit. Meanwhile, the output voltage of a feedback branch is taken as the following output voltage of the current output terminal. The invention can provide the DC small current with high precision.

The invention relates to an adjustable constant current source integrated chip and a manufacturing method. The adjustable constant current source integrated chip comprises a monocrystalline silicon N-type polished wafer which serves as an N-doped region, an N+ heavily doped region is arranged on the back of the N-doped region, a triode Q2, a current regulative diode (CRD), a triode Q1 and a resistor R are arranged on the front of the N-doped region, one end of an N+ doped region of the resistor R is connected with an N+ doped region of the triode Q2, meanwhile, the N+ doped region of the resistor R serves as the cathode of the constant current source integrated chip, the other end of the N+ doped region of the resistor R is respectively connected with an N+ doped region of the triode Q1 and a P doped region of the triode Q2, a P doped region of the triode Q1 is respectively connected with a P doped region of the CRD, the P doped region of the triode Q2 and an N doped region of the triode Q2, an N doped region of the CRD is respectively connected with the P doped region and a second N+ doped region of the CRD, and the N+ heavily doped region serves as the anode of the constant current source integrated chip.

The invention relates to an adjustable constant current source integrated chip and a manufacturing method. The adjustable constant current source integrated chip comprises a monocrystalline silicon N-type polished wafer which serves as an N-doped region, an N+ heavily doped region is arranged on the back of the N-doped region, a triode Q2, a current regulative diode (CRD), a triode Q1 and a resistor R are arranged on the front of the N-doped region, one end of an N+ doped region of the resistor R is connected with an N+ doped region of the triode Q2, meanwhile, the N+ doped region of the resistor R serves as the cathode of the constant current source integrated chip, the other end of the N+ doped region of the resistor R is respectively connected with an N+ doped region of the triode Q1 and a P doped region of the triode Q2, a P doped region of the triode Q1 is respectively connected with a P doped region of the CRD, the P doped region of the triode Q2 and an N doped region of the triode Q2, an N doped region of the CRD is respectively connected with the P doped region and a second N+ doped region of the CRD, and the N+ heavily doped region serves as the anode of the constant current source integrated chip.

The application discloses an LED driving device, a control circuit and a control method thereof. The LED drive control circuit includes: a conduction time control circuit, used to generate a first control signal according to the sawtooth wave signal and the first reference voltage; a current average value acquisition circuit, used to generate an average current reflecting the average value of the output current according to the current sampling signal signal; a proportional superposition circuit for superimposing the average current signal and the sawtooth wave signal in proportion to generate a superposition signal; a comparison circuit for comparing the superposition signal with a second reference voltage to generate a second control signal ; an OR gate, used to generate a reset signal according to the first control signal and the second control signal; a set signal generating circuit, used to generate a set signal; and an RS flip-flop, used to generate a reset signal according to the reset signal and The set signal generates a switch control signal. The LED drive control circuit can omit the compensation network of the regulation loop, realize high power factor, and does not need a discharge circuit when it is applied to the dimming of silicon controlled rectifiers.

The invention discloses a buck-boost control circuit of an LED (Light Emitting Diode) lamp, which has the outstanding advantages of wide output voltage range, good constant current characteristic, high efficiency, small size, simple circuit, low cost, high reliability and so on; the control circuit comprises a direct current power supply, an LED, a pulse width modulating circuit, a switching tube, an inductance coil with a magnetic core, an auxiliary coil and an output diode, wherein a control electrode of the switching tube is connected with the pulse width modulating circuit; an output electrode of the switching tube is connected with a current sampling resistor; an input electrode of the switching tube is connected to a direct current power supply by the inductance coil; an anode of the output diode is connected with one end of the inductance coil; a cathode of the inductance coil is connected with an anode of the LED; a cathode of the LED is connected with the other end of the inductance coil; the auxiliary coil is connected with a voltage feedback end FB of the pulse width modulating circuit; and a CS of the pulse width modulating circuit is connected with the current sampling resistor; a starting end Vin of the pulse width modulating circuit is connected with the direct current power supply by a resistor.

The invention relates to semiconductor technology, in particular to a JFET device and a manufacturing method thereof. The JFET device of the present invention is characterized in that the junction depth of the P+ gate region 1 is uneven, from one end near the N+ drain region 2 to the junction of the P+ gate region 1 near the N+ source region 3. The depth gradually increases. The beneficial effect of the present invention is that the constant current characteristic is better, and the requirement of smaller constant current precision can be met. The invention is particularly applicable to JFET devices and their fabrication.

The present invention disclosed a two -terminal constant current device, including the first exhaustive crystal tube and resistance, which is connected to the first end of the resistance to the first end of the resistance.The grille of the transistor is connected to the second end of the resistance. Among them, the first exhaustive crystal tube is the depletion of the nitride.The present invention uses the negative feedback effect of the resistor to achieve the constant flow effect of the second -term constant current device. The characteristics of the nitrogen -nitride crystal tube reaction speed, the high pressure resistance to bearing can be affected by small temperature, so that the second -terminal constant current flowsThe device has the advantages of fast response speed, high breakdown voltage, high temperature resistance, good constant current characteristics, and high temperature stability.

According to the technical scheme, the intelligent elevator safety management system is characterized in that the intelligent elevator safety management system comprises a voltage stabilizing module, the voltage stabilizing module is electrically connected with a driving module, the driving module is electrically connected with an acquisition module, and the acquisition module is electrically connected with an elevator driver; the acquisition module is electrically connected with an output open-short circuit protection module, a sampling resistor open-short circuit protection module, an under-voltage protection module and an output overvoltage protection module; the voltage stabilization module is electrically connected with an over-temperature debugging module, and the over-temperature debugging module is electrically connected with a temperature detection module. The voltage output by the system is stably adjusted through the voltage stabilizing module, the circuit of the system is detected through the acquisition module, then the stable voltage is reversely controlled and adjusted through the feedback adjusting module, the stability and the safety of the system are kept, the temperature of the system is detected through the temperature detecting module, output of the adjusting current is achieved, and the stability and the safety of the system are improved. And carrying out cooling regulation on the system.

The invention relates to semiconductor technology, particularly a JFET (junction field-effect transistor) device and a manufacturing method thereof. A shallow groove auxiliary layer 13 is introduced to one end of a gate region of the JFET device and is adjacent to the side of the source end; and thus, the shallow groove auxiliary layer 13 is utilized to reduce the ditch modulation effect, thereby implementing small variable rate within wide voltage input range. The device has favorable constant-current characteristic on the basis of uncomplex manufacturing technique, has small variable rate within wide voltage input range, can satisfy the demand for lower constant-current precision, and is especially suitable for low-power LED (light-emitting diode) lamp constant-current drive. The method is especially suitable for low-power LED lamp constant-current JFET devices.

The invention relates to electronic techniques, and provides a constant-current drive circuit of an LED switching power supply. The constant-current drive circuit comprises a rectification filter circuit, a power tube, an RS flip-flop, an oscillator and an operational amplifier. Two input ends of the RS flip-flop are respectively connected with an output end of the operational amplifier and the oscillator, and a Q end of the RS flip-flop is connected with a grid of the power tube. The constant-current drive circuit of the LED switching power supply is characterized in that the operational amplifier is connected with the input ends of the RS flip-flop through a delay doubling circuit. The constant-current drive circuit of the LED switching power supply has the advantages that the delay doubling circuit is added in a loop circuit compared with an existing BUCK structured constant-current drive circuit, and enables output current to be unrelated to LED voltage, clock periods and intensity of inductance, and therefore the constant-current drive circuit is good in constant-current characteristic.

The invention relates to an inductive energy-storage microsecond-grade high-power pulse current source comprising an inductive charging circuit, an inductive discharging circuit and a clamping circuit, wherein the inductive charging circuit is a series loop which consists of an excitation power supply V2, an inductor L and a switch tube; the inductive discharging circuit is a series loop which consists of a loader, a fly-wheel diode D1 and the inductor L; and the clamping circuit is connected with the inductive charging circuit in a spanning way. The invention can generate a current-controllable high-power pulse power supply on the negative-resistance loader, has adjustable striking voltage, not only has very well constant-current characteristics, but also can fast respond to plasma arcs and realize the ultrafast switching of striking arcs and constant currents.

The invention provides an SOI lateral constant-current diode and a manufacturing method thereof, and belongs to the technical field of semiconductor power devices. The lateral constant current diode is formed by connecting a plurality of cell interdigitals with the same structure; the cell comprises a substrate, a buried oxide layer, first conductive type lightly doped silicon, a second conductivetype diffusion well region, a first conductive type channel injection region, a second conductive type heavily doped region, a first heavily doped region, a second heavily doped region, an oxidationmedium layer, a metal anode and a metal cathode, wherein the first heavily doped region and the second heavily doped region are of the first conductivity type. The constant-current diode adopts the SOI technology, and adverse effects caused by substrate leakage current in an integrated system can be effectively prevented.

The invention relates to electronic techniques, and provides a constant-current drive circuit of an LED switching power supply. The constant-current drive circuit comprises a rectification filter circuit, a power tube, an RS flip-flop, an oscillator and an operational amplifier. Two input ends of the RS flip-flop are respectively connected with an output end of the operational amplifier and the oscillator, and a Q end of the RS flip-flop is connected with a grid of the power tube. The constant-current drive circuit of the LED switching power supply is characterized in that the operational amplifier is connected with the input ends of the RS flip-flop through a delay doubling circuit. The constant-current drive circuit of the LED switching power supply has the advantages that the delay doubling circuit is added in a loop circuit compared with an existing BUCK structured constant-current drive circuit, and enables output current to be unrelated to LED voltage, clock periods and intensity of inductance, and therefore the constant-current drive circuit is good in constant-current characteristic.

The invention discloses a collector for vibration monitoring of a shield tunneling machine, which comprises a communication module, wherein the communication module comprises an RS455 communication circuit, the RS455 communication circuit comprises a bidirectional voltage stabilizing diode DZ1, a bidirectional voltage stabilizing diode DZ2, a bidirectional voltage stabilizing diode DZ3, a resistor R48, a resistor R49, a resistor R52, a resistor R54, a resistor R56, a resistor R59, a resistor R58, a resistor R55, a capacitor C79 and a chip U19, the model of the chip U19 is ADM2486, a second pin of the chip U19, an eighth pin of the chip U19 and the other end of the resistor R55 are all grounded GND; and one end of the capacitor C79, one end of the resistor R49 and the sixteenth pin of the chip U19 are connected with a power supply VCC-S5V2. The collector has the advantages that interference in the collection process is avoided, and the final analysis result is accurate.

The invention discloses a control circuit and method for a switching power converter. The switching power converter comprises a power conversion circuit, a sampling resistor and a switching power controller. Output currents are provided for the switching power converter through the power conversion circuit. The switching power controller comprises a power switch, an error amplifier, a comparator circuit and a logic and drive circuit. The power switch is used for controlling power supply of the power conversion circuit, and the sampling resistor is coupled to the power switch and provides sampling voltage signals. The error amplifier is used for receiving the output current equivalent value and the preset threshold value of the switching power converter so as to generate error voltages, wherein the output current equivalent value indicates the amplitude of the output currents of the switching power converter. The comparator circuit is used for comparing the sampling voltage signals and the error voltages and generating comparison output signals. The logic and drive circuit is used for generating drive signals, wherein when the comparison output signals generated by the comparator circuit indicate that the sampling voltage signals excess the error voltages, the drive signals switch off the power switch.