29 results about "Bleeder resistor" patented technology

The invention discloses a high-voltage discharge circuit suitable for a storage battery power supply and an electric flame stove. The high-voltage discharge circuit comprises an inversion driving module, a boosting transformer T1, at least three groups of active bridge rectifier modules and discharge modules corresponding to the active bridge rectifier modules. Through combination of driving of the active bridge rectifier module, voltage / current double-closed-loop feedback and real-time PWM signal output control of the control chip U1, current difference of each discharge branch is eliminated, the problem of uneven branch current is solved, and ring current and reactive power loss between branches are eliminated; a diode in a voltage doubling rectifying circuit and a bleeder resistor of a resonance circuit in the prior art are abandoned, an active bridge type rectifying module is adopted for driving, a PWM signal is dynamically adjusted through the low ESR characteristic of a capacitor C1 and closed-loop control, extra power loss is avoided, the working temperature of the circuit is controlled to be below 85 DEG C, and the service life of the circuit is prolonged. And the continuous service life of components in the circuit is prolonged.

The invention discloses an electric energy discharge control device. The energy storage circuit is used for storing potential storage electric energy; the bleeder circuit is used for releasing the potential storage electric energy through a bleeder resistor and a bleeder transistor which are connected in series; the reference voltage setting circuit is used for outputting a reference voltage signal; the bleeder sampling feedback circuit is used for outputting a bleeder sampling feedback electric signal according to the bleeder sampling current of the bleeder resistor; the post-stage voltage feedback circuit is used for outputting a post-stage voltage feedback electric signal according to the potential storage voltage; and the conduction degree of the discharge transistor is controlled according to the post-stage voltage feedback electric signal, the reference voltage signal and the discharge current collection feedback electric signal. The conduction degree of the bleeder transistor is dynamically controlled according to the bleeder current collection feedback electric signal and the post-stage voltage feedback electric signal, so that the change of potential storage electric energy of the energy storage device is dynamically adapted, the bleeder power and the current of the bleeder circuit are stable and controllable, and a higher bleeder rate can be realized under the condition that the bleeder power and the current are kept unchanged.

The invention discloses a PFC (Power Factor Correction) circuit suitable for electrode high-voltage discharge. The PFC circuit comprises an EMI (Electro-Magnetic Interference) filtering module, a starting protection module, a PFC power conversion module and a PWM (Pulse-Width Modulation) switch type auxiliary power supply module which are connected in sequence. The EMI filtering module realizes bidirectional suppression of interference, and when the circuit is powered off, the bleeder resistor enables the common mode inductor and the differential mode capacitor to rapidly discharge, so that secondary interference is prevented; according to the PWM switch type auxiliary power supply module, a high-voltage area and a low-voltage area are isolated, and it is guaranteed that the power supply input pin of the control chip U2 / U3 can be within the normal working voltage; according to the invention, the control chip U2 limits the PWM duty ratio of the control chip U3 through the control logic, so that overcurrent protection is realized; when the MOS tube Q1 / Q2 is conducted, the resistor R22 consumes energy generated by discharging of the capacitor C21, meanwhile, resonance between the capacitor C21 and the energy storage inductor L2 is restrained, high-frequency electromagnetic interference is prevented, and electromagnetic compatibility of the whole system is achieved.

The invention relates to the technical field of power electronics, and discloses an alkaline electrolytic cell shutdown discharge circuit which comprises a voltage sampling module, a logic control module, a solid-state switch driving module, a bleeder resistor module and a protection module. The voltage sampling module monitors direct-current high voltage of the electrolytic cell in real time and generates low-voltage signals. The logic control module receives the low-voltage signal, compares preset upper and lower threshold voltages, and generates a control signal or a stop signal. And the solid-state switch driving module amplifies the control signal and drives the power switch device to be switched on. The bleeder resistor module converts electric energy into heat energy for dissipation through a power switch device and a bleeder resistor. The protection module absorbs turn-off surges through a fast recovery diode or an RC circuit to protect the power switch device. The system adopts an all-solid-state device to replace a mechanical relay, avoids arc generation, realizes rapid and controllable discharge through closed-loop control, prolongs the service life of equipment, and is suitable for shutdown discharge requirements of the alkaline electrolytic cell in an industrial environment.

The invention discloses a back electromotive force discharge method and system for a direct-current brushless fan of a breathing machine. The method comprises the following steps: receiving a rotating speed adjusting instruction of the direct current brushless fan of the breathing machine, and calling a preset feedforward MAP to obtain an initial discharge duty ratio; according to the obtained initial discharge duty ratio, a discharge circuit is controlled to discharge, and whether rotating speed switching is completed or not is judged; if the judgment is completed, returning the discharge duty ratio to zero, and ending the control; and if the judgment is not completed, acquiring the voltage change rate of the direct current bus in real time by using a bus voltage change rate detection circuit, and dynamically adjusting the discharge duty ratio based on the voltage change rate until the rotation speed switching is completed. The direct-current brushless fan can solve the problems of serious heating, inaccurate discharge and the like of the bleeder resistor, and ensures that the direct-current brushless fan stably and reliably operates under different rotating speed working conditions on the basis of a simple circuit and low cost.

This utility model discloses a capacitive release test device, including an AC voltage source U s The system comprises a high-precision capacitor module M1, a basic capacitor module M2, a bleeder resistor R, a single-pole miniature circuit breaker QF3, and a single-pole miniature circuit breaker QF4. The high-precision capacitor module M1 includes a single-pole miniature circuit breaker QF1 and a pF-level capacitor C. P Single-pole miniature circuit breaker QF2 and μF-level capacitor C s The basic capacitor module M2 includes a circuit board B, on which several ceramic plate slots Vu are arranged. Each ceramic plate slot Vu is connected to the positive lead p+ of the positive copper claw T+ and the negative lead p- of the negative copper claw T-. This utility model discloses a capacitive release test device that achieves a large capacitance value of over 86nF through the parallel design of 17 ceramic capacitor cells with different capacitance values. The capacitor cells are arranged in a plug-and-play manner to form the basic capacitor module M2, meeting the 27 capacitance values ​​required for capacitive release tests of electrical appliances from 12V to 600V.

The utility model provides a high-voltage non-stroboscopic lamp strip compatible with dimming of various silicon controlled rectifiers. Comprising a rectifier bridge DB1, a linear constant current driving chip U1, a dimming discharge chip U2, a discharge resistor R7, a discharge resistor R8, a U2 sampling resistor R6, a first lamp string, a second lamp string, an electrolytic capacitor E1, an electrolytic capacitor E2, an electrolytic capacitor discharge resistor R4, an electrolytic capacitor discharge resistor R5, a U1 sampling resistor R1, a U1 sampling resistor R2, a U1 sampling resistor R3, a fly-wheel diode D1, a fly-wheel diode D2 and a fly-wheel diode D3, one end of the bleeder resistor R7 is connected with a pin 2 of the rectifier bridge DB1, and the other end of the bleeder resistor R7 is connected with one end of the bleeder resistor R8. The beneficial effects of the utility model are that the circuit can be compatible with silicon controlled dimmers of different specifications, and solves a problem that a lamp strip is liable to flicker under the condition of low power in a dimming process.

The invention provides a negative-voltage-surge-resistant reverse-connection-preventing direct-current filtering assembly, and relates to the technical field of electronics, the negative-voltage-surge-resistant reverse-connection-preventing direct-current filtering assembly comprises a reverse-connection-preventing circuit, a leakage circuit, an acquisition control circuit and an input common-mode filtering circuit, the reverse-connection-preventing circuit comprises a first NMOS tube, the drain electrode of the first NMOS tube is connected with a negative electrode bus, the source electrode of the first NMOS tube is electrically connected with a first system ground end, and the drain electrode of the first NMOS tube is electrically connected with a second system ground end; the grid is electrically connected with the positive bus through the target resistor; the acquisition control circuit is used for acquiring a bus voltage and controlling the first NMOS tube to be turned off within a first preset duration when the bus voltage is smaller than or equal to a first preset voltage threshold value; and when input power failure occurs, discharging is performed on the group of capacitors through the first bleeder resistor when the bus voltage drops to a second preset voltage threshold value, and discharging is performed on the group of capacitors through the second bleeder resistor when the bus voltage drops to a preset safety voltage value from the second preset voltage threshold value. According to the technical scheme, the effect of improving the reliability of the direct current filtering assembly is achieved.

The utility model discloses a high-integration-level steering wheel system, which relates to the technical field of mobile robots and comprises a hub motor, a wheel carrier, a driver, a bleeder resistor, a side cover, a rotating shaft, a limiting disc, a right-angle speed reducer and a steering motor. The hub motor comprises a rubber wheel, a steel ring, a driving motor front cover, a driving motor rear cover, a front bearing, a rear bearing, a split type encoder, a motor shaft, a corrugated gasket, a motor stator, a motor rotor and a framework oil seal. The utility model has the characteristics of good sealing performance, strong anti-vibration capability, high integration level and low cost, and is suitable for outdoor occasions with strict spatial dimension requirements. The system can adapt to various outdoor environments, and the product integration degree is further improved.

A transmitting module and a method for transmitting differential signals in a serial bus system. The transmitting module has a first to a fourth transmission stage connected in a full bridge, in which the first and fourth transmission stage are connected in series and the third and second transmission stages are connected in series, and a current limiting circuit for measuring and evaluating currents through a first and a second bleeder resistor which are connected to the full bridge. The first to fourth transmission stages generate differential bus signals for a bus in response to the two different values of a digital transmit signal such that the transmitting module generates, in its first operating mode, a first or second bus state on the bus and generates, in its second operating mode, a third or fourth bus state.

The invention belongs to the technical field of motor control, and particularly relates to a steering engine braking energy discharge control circuit and method based on an FPGA. The circuit comprises a voltage acquisition circuit, a PWM generation module, a temperature acquisition circuit and a bleeder power circuit, the bleeder power circuit comprises a bleeder tube, a bleeder resistor, a first temperature sensitive resistor and a second temperature sensitive resistor, the drain electrode of the bleeder tube is connected with one end of the bleeder resistor, and the grid electrode of the bleeder tube is connected with the output end of the PWM generation module; the source electrode of the bleeder tube and the other end of the bleeder resistor are connected with the input end of the voltage acquisition circuit; one end of the first temperature-sensitive resistor is connected with a first forward input end of the temperature acquisition circuit, and the other end of the first temperature-sensitive resistor is connected with a first reverse input end of the temperature acquisition circuit; and one end of the second temperature-sensitive resistor is connected with a second positive input end of the temperature acquisition circuit, and one end of the second temperature-sensitive resistor is connected with a second negative input end of the temperature acquisition circuit.

An electrostatic coating machine according to the present embodiments can reduce the risk of sparking even when setting a higher line speed than before when performing coating according to a proximity painting method. In the coating machine that performs electrostatic coating by use of a high voltage generated by a cascade, when a time constant τ is defined as the product of a total capacitance Co of the electrostatic coating machine and a bleeder resistor R1, the product of the total capacitance Co and the bleeder resistor R1 is set so that the time constant τ is 0.005 to 0.050.

The present application relates to a kind of gallium nitride motor controllers and resonance elimination method, belong to power electronics field, solve when using traditional RC absorption circuit, resistance is easy to overheat damage under high-frequency switching condition, leading to the problem of protection function failure.Control device includes: power supply, with motor series connection, control motor's on-off electricity, including the gallium nitride switch tube with parasitic capacitance;Resonance elimination circuit, connected to power supply control device, freewheeling diode and the absorption capacitor and bleeder resistor connected in parallel are connected in series, when gallium nitride switch tube is in the off stage, current is through freewheeling diode forward conduction, absorption capacitor is charged so that absorption capacitor voltage gradually rises;When gallium nitride switch tube is in energy bleeder stage and capacitor rises to predetermined voltage, discharge is carried out through resistor, and electric energy is converted into heat energy and is smoothly dissipated.Effective inhibition of high-frequency resonance and reliable protection of switch tube are realized.

The invention discloses a closed-loop double-feedback collaborative robot regeneration control method and device and a storage medium, and belongs to the technical field of servo bus voltage regeneration control, and the method comprises the following steps: continuously obtaining a bus voltage and a bleeder resistor temperature of a collaborative robot; comparing the real-time bleeder resistor temperature with a preset bleeder resistor temperature threshold interval set, and judging a bleeder resistor temperature threshold interval specifically corresponding to the bleeder resistor temperature; according to different temperature threshold intervals of the bleeder resistor, different weight analysis algorithms are adopted to calculate weight gains, and the weight gains are obtained; a PI algorithm is adopted to calculate the real-time bus voltage and a preset bus voltage target value to obtain a PI calculation result, and the PI calculation result and the weight gain are summed to obtain an IGBT turn-on duty ratio value; and controlling the switching action of the IGBT according to the IGBT turn-on duty ratio value. When the servo joint of the robot is braked quickly, the bleeder resistor can work within the limit load for a long time, and the temperature abnormity alarm probability of the bleeder resistor is reduced.

A High Electron Mobility Transistor, HEMT, structure (1) having a gate (G), a source (S) and a drain (D), said HEMT structure comprising a depletion-mode transistor (3) having a breakdown voltage, current limiting means (9) arranged for ensuring that a drain source current of said HEMT structure, in an off-state of said HEMT structure, is at most 20 nA / mm, being a current per unit gate length of the depletion-mode transistor, wherein the HEMT structure may comprise a cascode configuration of said depletion-mode transistor with an enhancement mode transistor (6). The current limiting means may be embodied by a bleed resistor 9 that may additionally prevent the enhancement-mode transistor to enter avalanche. The bleed resistor may be connected between the gate terminal of the enhancement-mode transistor and the source terminal of the enhancement-mode transistor.

The invention discloses a fast rear-end auxiliary tube control low-end ideal diode based on an NMOS (N-channel Metal Oxide Semiconductor) tube, which relates to the technical field of power diodes and comprises a power supply VCC, an NMOS main tube V1, a comparator circuit, a bias power supply and a driving circuit, the comparator circuit comprises two independent auxiliary tubes or pair tubes and a resistor; the comparator circuit is used for comparing voltages at two ends of a source electrode and a drain electrode of the NMOS main tube V1, and a comparison signal of the comparator circuit transmits an amplification signal to a grid electrode of the NMOS main tube V1 through the driving circuit to control the conduction and cut-off of the NMOS main tube V1; and a current bleeder resistor R3 is also connected between the grid electrode and the source electrode of the NMOS main tube V1. Compared with the prior art, the fast type rear-end auxiliary tube control low-end ideal diode based on the NMOS tube has the advantages that backward flowing can be prevented, and a pre-stage circuit can be protected.

The utility model relates to the technical field of filters, in particular to a small-size high-voltage filter. Aiming at an application scene with strict space limitation, the filter adopts the design of a 6061 aviation aluminum integrated milling shell, a polyether-ether-ketone (PEEK) insulating plate, an output interface formed by combining a gold-plated copper platform with a flexible lead and the like, so that light weight and miniaturization are realized. Main devices comprise a common-mode inductor, a differential-mode capacitor, a common-mode capacitor and a bleeder resistor to form a first-order low-pass filter circuit, EMI interference of 10 kHz to 10 MHz is effectively restrained, and the electromagnetic compatibility requirement (GJB151ACE102) under the working condition of direct current 540V / 50A is met. The size of the product is only 40cm < 3 >, the weight is 128g, and the product has high insulativity, low contact resistance and excellent vibration resistance, and is suitable for the fields with strict requirements on size and reliability, such as aerospace and the like.

The invention discloses a high-voltage servo driver discharge device based on high-resistance isolation sampling, and the discharge device employs a high-resistance isolation bus sampling design, a bus high voltage is scaled down into a sampling voltage, and the sampling voltage is compared with a discharge threshold voltage through a comparator after conditioning. And the output of the comparator controls the grid voltage of the SiC MOS tube through the isolation driving circuit, so that the on-off of the bleeder resistor connected between the bus voltage and the ground is controlled, and the purpose of discharging when the bus voltage exceeds a threshold value is achieved. The device can protect the high-voltage servo driver from instantaneous high-voltage impact of bus fluctuation, back electromotive force and the like, and normal work of the servo driver is maintained.

The invention provides a full-wave rectification absorption circuit and a full-bridge conversion circuit, and relates to the technical field of power electronics, and the full-wave rectification absorption circuit comprises a full-wave rectification module composed of switching devices, and a peak absorption module composed of a bleeder resistor, at least one absorption capacitor and at least one absorption diode. The absorption capacitor is connected in parallel with the absorption diode, the absorption capacitor is also connected in series with the bleeder resistor, and the switching device is connected in series between the absorption capacitor and the absorption diode; or the absorption capacitor is connected in parallel with the bleeder resistor, and the absorption capacitor is also connected in series with the switching device and the absorption diode. By adjusting the connection mode of a bleeder resistor, an absorption capacitor and an absorption diode in the peak absorption module, energy stored in the absorption capacitor discharged by the bleeder resistor can be reduced, and energy transmitted from the absorption capacitor to an output capacitor of the full-bridge conversion circuit can be increased. Therefore, the energy utilization rate of the full-wave rectification absorption circuit can be improved.

The application provides a BME MLCC with a bleeder resistor and a preparation method thereof, and belongs to the technical field of patch components. A conductive paste is first coated on the surface of two opposite edge regions of one side of a substrate, first sintering is performed, and a conductive film layer is obtained; a resistor paste is second coated on the surface of the substrate, second sintering is performed, a resistor layer is formed, and a resistor is obtained; the resistor and the BME MLCC are bonded in a non-terminal electrode region by using an adhesive, the conductive film layer of the resistor is arranged opposite to the terminal electrode of the BME MLCC during the bonding, the terminal electrode and the conductive film layer are welded, and the BME MLCC with the bleeder resistor is obtained. The resistor and the capacitor are respectively manufactured, so that the product production qualified rate is improved, the resistor and the capacitor are bonded and welded after being manufactured, and thus the product performance requirements can be met, and the product manufacturing cost can be effectively reduced.

The invention discloses a rapid and safe super capacitor charging and discharging control circuit and a method thereof, and relates to the technical field of circuit protection. Comprising a power taking device, a Boost plate, a pre-charging plate, a first pre-charging relay K1, a second pre-charging relay K2, a bypass relay K3, a bleeder relay K4, a first pre-charging resistor R1, a second pre-charging resistor R2, a bleeder resistor R3, a first diode D1, a second diode D2, a third diode D3, a super capacitor and an electric device. According to the invention, the temperature of the first pre-charging resistor R1 and the second pre-charging resistor R2, the temperature and the current of the power taking equipment and the voltage rising speed of the super capacitor can be monitored in real time, and the most reasonable closing point of the second-stage relay can be found, so that the quick charging of the super capacitor is realized; if the power supply system is suddenly powered off, the pre-charging operation can still be continued according to the current voltage on the super capacitor after the power supply system is powered on again.

The invention discloses an electro-hydrostatic driving device matched with an intelligent load and a control method of the electro-hydrostatic driving device. The electro-hydrostatic driving device comprises a controller, a variable speed motor, a fixed displacement pump, an oil supply module, an actuator module, hydraulic control one-way valves, electric control throttle valves and pressure sensors, wherein the hydraulic control one-way valves, the electric control throttle valves and the pressure sensors are symmetrically arranged on two load oil ways. The core lies in that the controller judges whether the actuator cylinder is in a load-loading or reverse-loading working condition in real time according to the difference value of pressure signals detected by the two pressure sensors, and independently controls the opening degree of the two electric control throttle valves according to the load-loading or reverse-loading working condition. Under the working condition of loading, mechanical energy of the load is converted into heat energy of hydraulic oil to be discharged by adjusting the opening degree of a throttle valve on the non-driving side. According to the electro-hydrostatic driving device controller, the problems of huge size and difficulty in heat dissipation caused by a built-in bleeder resistor of the controller are effectively solved, the size and size of the electro-hydrostatic driving device controller are reduced, and miniaturization and intelligentization of the device are realized.

A pulse-supported capacitor with a bleed resistor and its manufacturing method are disclosed. The pulse-supported capacitor includes a capacitor body and two supports disposed opposite to each other on both sides of the capacitor body. The capacitor body includes a capacitor chip, two end electrodes disposed opposite to each other at both ends of the capacitor chip, and a bleed resistor disposed on the top surface of the capacitor chip and connected between the two end electrodes. The two supports are respectively connected to the two end electrodes. Each support includes a connecting frame connected to the end electrodes, a support foot disposed below the connecting frame and connected to a circuit board, and a connecting lead disposed between the frame and the support foot. This application defines the structure of the pulse-supported capacitor and provides a bleed resistor on its surface, so that the pulse-supported capacitor can form a path with the bleed resistor after the circuit is interrupted, releasing the residual energy of the capacitor through the resistor, thereby improving the safety of the circuit.

The utility model discloses a three-phase four-wire system AC voltage acquisition circuit, which comprises a differential amplification circuit, a high-value resistance network and a voltage reference circuit, and is characterized in that the differential amplification circuit comprises three differential amplifiers, namely a first differential amplifier, a second differential amplifier and a third differential amplifier; the voltage reference circuit is used for lifting a null line; the high-value resistance network comprises a residual voltage bleeder resistor used for open-phase input residual voltage discharge and a resistance attenuation network used for attenuating a high-voltage signal. A residual voltage bleeder resistor is connected between each live wire and the null line; a resistance attenuation network is connected between each live wire and the inverted input end of the corresponding differential amplifier, and after the in-phase input ends of the three differential amplifiers are connected together, a resistance attenuation network is also connected between the joint and the zero line. The alternating-current voltage acquisition circuit not only can realize alternating-current voltage acquisition, but also is low in cost, small in size, small in occupied space, convenient to install and high in safety.

The utility model discloses a crosstalk suppression circuit, an MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor) driving circuit and a bridge type functional circuit, and relates to the field of power electronic device control. The output end of a driving chip is respectively connected with the grid electrode of an MOSFET corresponding to the MOSFET driving circuit and the first end of a controllable switch module through a driving resistor; the source electrode of the MOSFET is connected with the other end of the bleeder resistor, one end of the clamping matching resistor and the cathode of the first voltage stabilizing diode, the other end of the clamping matching resistor is connected with the power supply end of the driving chip, and the grounding end of the driving chip, the anode of the first voltage stabilizing diode and the control end of the controllable switch module are connected and then grounded. The first capacitor is connected in parallel with the driving resistor, and the first capacitor can discharge to realize suppression when forward crosstalk occurs; when negative crosstalk occurs, the controllable switch module is switched on to realize negative crosstalk suppression; according to the scheme, a path of control signal cost does not need to be additionally introduced, and reliable operation of the MOSFET under high switching frequency is ensured.

The utility model discloses a high-voltage power supply personal protection circuit which comprises a depletion type MOS tube and a first bleeder resistor, a drain electrode of the depletion type MOS tube is connected with an output positive electrode of a high-voltage power supply, a source electrode of the depletion type MOS tube is connected with one end of the first bleeder resistor, the other end of the first bleeder resistor is connected with an output negative electrode of the high-voltage power supply, and the other end of the first bleeder resistor is connected with an output positive electrode of the high-voltage power supply. The grid electrode of the depletion type MOS tube is connected with the output negative electrode of the high-voltage power supply, and when the high-voltage power supply outputs voltage, the depletion type MOS tube works until the output voltage of the high-voltage power supply is 0V. According to the utility model, the characteristic of the depletion type MOS tube is used as a constant current source, the structure is simple, the performance is stable, the space volume of a machine can be saved, and the problem that the existing constant current source does not work due to internal power failure of the machine is solved.

A method for fabricating a BME MLCC with a bleed resistor at high temperature is disclosed. The BME MLCC includes a ceramic core, two end electrodes disposed opposite each other on both sides of the ceramic core, a resistive layer disposed on the surface of the ceramic core between the two end electrodes, and two overlapping electrodes respectively connected between the end of the resistive layer and the opposite end electrodes. This application, by defining the structure of the BME ceramic capacitor and using a step-by-step sintering process, sets overlapping electrodes between the copper end electrodes and the resistive layer. While achieving a conductive connection between the copper end electrodes and the resistive layer, it avoids the risk of a sintering reaction between the copper end electrodes and the ruthenium oxide-based resistive layer at high temperature, so that the fabricated BME MLCC meets the required design requirements.

A non-isolated light emitting diode (LED) driver for driving an LED load, the driver comprising: a power stage comprising a switching element, an inductor and a diode, the power stage being arranged to receive a bus voltage; and an integrated circuit (IC) for controlling the switching element, where the IC includes: a start-up input, where the IC can be enabled based on a voltage provided to the start-up input; and a capacitor connected to the start-up input of the IC for providing the voltage to the start-up input; and a bleeder resistor connected between the bus voltage and the start-up input; and a discharge circuit arranged to discharge the capacitor based on a standby signal.

The invention discloses a fast front-end auxiliary tube control low-end ideal diode based on an NMOS (N-channel Metal Oxide Semiconductor) tube, which relates to the technical field of power diodes and comprises a power supply VCC, an NMOS main tube V1, a comparator circuit, a bias power supply and a driving circuit, the comparator circuit comprises two independent auxiliary tubes or geminate transistors which have the same parameters and are packaged together, and a resistor, a source electrode and a drain electrode of the NMOS main tube V1 are respectively connected to a load low-end potential VD and a power supply negative electrode GND, and a current bleeder resistor R3 is connected between a grid electrode and the source electrode; the comparator circuit is connected with a bias power supply and used for comparing the magnitude of a load low-end potential VD and the magnitude of a power supply negative electrode GND, and the driving circuit is connected to a front-end transistor of the comparator circuit to obtain an input signal. Compared with the prior art, the fast front-end auxiliary tube control low-end ideal diode based on the NMOS tube has the advantages that conduction and cut-off of the low-end ideal diode are controlled in an accelerated mode.