153 results about "Voltage spike" patented technology

The invention discloses a power module. The power module comprises a direct current busbar, a radiator, an IGBT module I and an IGBT module II, the IGBT module I and the IGBT module II are respectively arranged on a mounting surface I and a mounting surface II of the radiator; the direct-current busbar comprises a direct-current busbar I, a direct-current busbar II, a direct-current busbar III and a direct-current busbar IV; the two ends of a fourth direct-current busbar are connected with the first IGBT module and the second IGBT module respectively, and the middle of the fourth direct-current busbar is connected with the middle of a third direct-current busbar. The two ends of the direct current busbar III are respectively connected with the direct current busbar I and the direct current busbar II; the direct current busbar I and the mounting surface I as well as the direct current busbar II and the mounting surface II are oppositely arranged and parallel to each other; the first direct current capacitor assembly is connected with the first direct current busbar, and the second direct current capacitor assembly is connected with the second direct current busbar. The influence of stray inductance is reduced by optimizing a current path, and the voltage spike at the switching moment is reduced due to the reduction of the stray inductance, so that the switching loss is reduced.

The invention discloses a SiC MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor) device structure for optimizing switching characteristics and a preparation method thereof, and provides a silicon carbide MOSFET device for reducing reverse output capacitance Crss, increasing input capacitance Ciss and increasing output capacitance Coss to improve Crosstalk voltage spike and a preparation method thereof. By introducing the composite gate oxide structure, the high-K material passivation layer and the P + structure at the bottom of the P-WELL into the planar silicon carbide MOSFET device, the reverse output capacitance Crss can be effectively reduced, the input capacitance Ciss can be increased, the output capacitance Coss can be increased, and finally, the Vgs voltage peak in the Crosstalk turn-off process can be effectively improved, and the performance of the device is improved. The breakdown and burnout of the device caused by overhigh voltage in the on-off process of the device are prevented, and the service life of the device is prolonged. Besides, the device structure and the preparation method are simple, and the effect is remarkable, so that high-performance and batch preparation and production can be realized, and the device has huge market potential and wide application prospects.

The invention belongs to the technical field of motor driving control, and discloses a space vector modulation strategy method for a permanent magnet synchronous motor, which comprises the following steps of: searching a region division and vector arrangement table by using regions in which Vlp and V are positioned to obtain an optimal vector sequence, and arranging vectors based on a principle of eliminating a peak of a CMV and minimizing switching operation times; and finally, calculating the duty ratio of a plurality of effective voltage vectors used for synthesizing the next period according to the amplitude-second balance principle. Compared with a control strategy that only one effective vector or two adjacent effective vectors are used in each control period, the virtual vector synthesized by the method is the same as the reference vector, and common-mode voltage spikes can be eliminated by the method; compared with NSPWM and AZPWM, the method has the advantages that area division and vector sorting are reasonably arranged, so that the switching action times are minimized, the switching loss is reduced, and the inverter efficiency is improved.

The utility model discloses a DC power supply input protection circuit. The transient absorption circuit is used for absorbing transient voltage spike pulse generated by input voltage of the power supply; the voltage stabilizing circuit is used for generating stable voltage when the power supply is input in a wide voltage range; the second voltage division circuit and the power supply output control switch circuit are connected in parallel and are arranged between the power supply input end and the power supply output end of the direct-current power supply, and the first voltage division circuit can divide the stable voltage generated by the voltage stabilizing circuit; the first voltage division circuit is connected with the in-phase end of the comparator to provide reference voltage for the comparator, the second voltage division circuit is connected with the anti-phase end of the comparator to provide input voltage for the comparator, and the comparator can compare the reference voltage with an input voltage signal. When the input voltage is higher than the reference voltage, the output end of the comparator outputs a signal for controlling the switching circuit to close to the power supply. The overvoltage protection circuit is sufficient and accurate in overvoltage protection, can be applied to a relatively wide voltage range, and is low in cost.

The disclosure concerns a resonant LLC converter, comprising a transformer comprising a primary side and a secondary side; a primary side circuit comprising primary side switches connected to the primary side of the transformer; a secondary side circuit comprising secondary side switches connected to the secondary side of the transformer; and a control unit configured to control the primary side switches and the secondary side switches; wherein the control unit is configured to perform a steady-state operation where switching frequencies of the primary side switches and of the secondary side switches are controlled to regulate an output voltage of the converter; and the control unit is configured to perform an overshoot control operation where an output voltage spike during a load transient is reduced by setting a control signal for the secondary side switches to low or OFF. The invention also concerns a control method for driving the above-mentioned converter.

The utility model discloses a clamping plate type titanium-based composite anode structure which comprises a composite conductive beam, a conductive connecting plate, a titanium mesh, a titanium structure frame and a titanium bolt, the composite conductive beam is connected with the conductive connecting plate, and the conductive connecting plate is connected with the titanium mesh; the number of the titanium structure frames is two, and a plurality of bolt holes are formed in the titanium structure frames. The titanium bolts penetrate through the bolt holes to clamp and fix the titanium mesh between the two titanium structure frames; and the top end of the titanium structure frame is connected with the composite conductive beam and the conductive connecting plate. According to the clamping plate type titanium-based composite anode structure provided by the utility model, the titanium mesh is clamped and fixed by the two titanium structure frames through the clamping plate type structure, so that the bending deformation of the titanium mesh can be reduced; the condition of voltage increase or short circuit caused by titanium mesh deformation in the electrolysis process is avoided; and the disassembly cost of reutilization of the structural member is reduced.

The invention discloses a compact single-stage matrix AC-DC power conversion device and a control method thereof. The power conversion device comprises a power module, a switch matrix, a resonant cavity, a rectifying circuit, a first follow current branch and a second follow current branch, the power module is connected with the switch matrix, the resonant cavity is connected with the power module, the switch matrix comprises a first bridge arm and a second bridge arm, the midpoint of the first bridge arm is connected with one end of a primary winding of the resonant cavity, and the midpoint of the second bridge arm is connected with the other end of a secondary winding of the resonant cavity. The midpoint of the second bridge arm is connected with the other end of the primary winding of the resonant cavity, the first freewheeling branch is connected with the first bridge arm in parallel, the second freewheeling branch is connected with the second bridge arm in parallel, and the first freewheeling branch, the second freewheeling branch, at least part of the first bridge arm, at least part of the second bridge arm, the power module and the resonant cavity form a freewheeling channel. Two ends of the rectification circuit are connected with the secondary winding of the resonant cavity. The compact single-stage matrix type AC-DC power conversion device can effectively eliminate voltage spikes and reduce loss.

A method for plasma processing a substrate includes: sustaining a plasma in a plasma processing chamber, the plasma processing chamber including a first electrode and a second electrode, where sustaining the plasma includes: coupling a source signal to the first electrode; and applying a bias signal to the second electrode, the bias signal having a spike waveform including a plurality of bias pulses, each of the bias pulses including a DC base voltage for a base duration and a triangular voltage spike having a rise time from the base voltage to a peak voltage and a fall time from the peak voltage to the base voltage, a sum of the rise time, the fall time, and the base duration including a pulse period, the applying including: independently adjusting the rise time and fall time to obtain a narrow energy spread of a mode at a high modal energy in an ion energy distribution function (IEDF) of an ion flux incident on the substrate, the narrow energy spread including a first width of the high energy mode of the IEDF that is smaller than a second width of the high energy mode of the IEDF obtainable using a rectangular pulse waveform.

A voltage controller (204) detects (604) a voltage spike (244) in an electrical signal received from an electrical power source (208). The voltage controller (204) is implemented using a single-loop control system in a stationary reference frame. The electrical signal includes voltage harmonics caused by a non-linear or unbalanced load (256). The voltage controller (204) includes a phase-compensated harmonic regulator (220) that regulates the voltage harmonics present in the electrical signal and receives a feedback voltage (240) of the single-loop control system. The feedback voltage (240) is a delayed version of an instantaneous voltage (236) of the electrical signal. The instantaneous voltage (236) is sub-transiently stabilized into a steady-state voltage (232) based on the feedback voltage (240). Sub-transiently stabilizing the instantaneous voltage (236) is performed within a single cycle after the voltage spike (244) is detected (604). The steady-state voltage (232) has a total harmonic distortion less than a threshold total harmonic distortion and the steady-state voltage has a balanced sinusoidal waveform.

The invention provides a power module, an electric drive assembly and a vehicle, and the power module comprises a plurality of sub-power modules, and each sub-power module corresponds to one phase; the number of the lining plates is multiple, each lining plate is provided with a reference surface, at least one sub-power module in the multiple sub-power modules is provided with one lining plate, and the sub-power modules are located in the reference surfaces; a plurality of direct current power terminals, the plurality of direct current power terminals and the plurality of lining plates are arranged in a one-to-one correspondence manner, the direct current power terminals are located in the reference surface, and the direct current power terminals are arranged at one ends of the lining plates; the number of the alternating current power terminals is multiple, and the multiple alternating current power terminals and the multiple lining plates are arranged in a one-to-one correspondence mode; and the plurality of capacitors are arranged in one-to-one correspondence with the plurality of lining plates, and the capacitors are located between the sub-power modules and the direct-current power terminals. According to the invention, the problem of how to effectively suppress the voltage spike in the switching process by the power module in the prior art is solved.

This invention relates to the field of gallium nitride (GaN) technology and discloses a GaN and MOS power module for a robot digital control unit, comprising a substrate, a front GaN structure, and a back GaN structure. The front GaN structure and the back GaN structure are located on opposite sides of the substrate, with an intermediate dielectric deposited between them. The front GaN structure includes a front buffer layer, a front GaN layer, a front aluminum gallium nitride layer, a front source electrode, a front gate electrode, a front P-type GaN layer, and a front drain electrode. This invention achieves normally-off operation through the front enhancement-mode GaN structure to improve system safety, and utilizes the back depletion-mode structure to provide high current drive capability. Simultaneously, the integrated capacitor structure formed by the front electrode, intermediate dielectric, and back electrode effectively absorbs voltage spikes and suppresses electromagnetic interference, thus enabling this power module to combine high-speed switching, low loss, and high reliability in a robot digital control unit.

The invention relates to the technical field of health management of silicon carbide MOSFET devices, in particular to a silicon carbide MOSFET gate oxide health state real-time monitoring circuit and method. The silicon carbide MOSFET gate-oxide health state real-time monitoring circuit comprises a differentiating circuit, a signal processing unit and a monitoring output unit, and synchronously outputs a first specific monitoring signal when a first voltage spike signal in a silicon carbide MOSFET turn-on stage is continuous; when the second voltage spike signal in the turn-off stage of the silicon carbide MOSFET is continuous, a second specific monitoring signal is synchronously output, and the duration time of the first specific monitoring signal and the duration time of the second specific monitoring signal are used for reflecting the gate-oxide health state of the silicon carbide MOSFET. According to the gate-oxide health state monitoring circuit, the resolution ratio can be effectively improved, only the gate signals are collected, the original working states of devices such as a driving resistor do not need to be changed, real-time online signal collection and low invasion of the monitoring circuit are kept, and the gate-oxide health state monitoring circuit and a driving circuit are easily integrated.

Apparatus and associated methods relate to a gate drive timing controller (GDTC). In an illustrative example, the GDTC may generate a power stage activation signal (PSAS) to control an output current of a MOSFET(s) of the power stage. Three pullup transistors, for example, may be electrically connected to the control output in parallel, configured to generate the PSAS as a function of a switch node voltage (Vsw) and a source inductance voltage (VLS) of the MOSFET. For example, a first pullup transistor may be activated when a PWM signal for the power stage is received, and deactivated based on the VLS. For example, a second pullup transistor may be synchronized with the PWM signal. For example, a third pullup transistor may be activated when the Vsw is detected. Various embodiments may advantageously generate the PSAS adaptively to reduce turn-on loss of the MOSFET while keeping a low transient voltage spike.

The invention discloses a gate oxide layer protection circuit, a chip and electronic equipment, and belongs to the technical field of electronic circuits. Two trigger signals are sent out in response to the voltage of a power rail through a series RC (Resistance-Capacitance) circuit; the series RC circuit responds to the condition that the voltage of the power rail is larger than a preset value, sends a connection trigger signal from a first node to connect the switching circuit, responds to the condition that the voltage of the power rail is smaller than the preset value and peak voltage appears, and sends a disconnection trigger signal from the first node based on the coupling effect of the first capacitor to cause the switching circuit to be disconnected. The first node is a common contact of the first resistor and the first capacitor; the functional circuit is connected with the first power rail, comprises a field effect transistor and is used for executing corresponding functions; the switching circuit responds to the connection trigger signal to connect the grid electrode of the field effect transistor and the second power rail, and responds to the disconnection trigger signal to disconnect the connection between the grid electrode of the field effect transistor and the second power rail; therefore, the reliability of the chip is improved.

This invention belongs to the field of power electronics technology, specifically relating to a single-phase high-frequency chain inverter and its modulation method, comprising: a primary-side full-bridge inverter circuit, including primary-side switching transistors K1, K3, K2, and K4; a secondary-side full-bridge frequency converter, including secondary-side switching transistors S1a, S2a, S3b, S4b, S1b, S2b, S3a, and S4a; a high-frequency transformer for connecting the primary-side full-bridge inverter circuit and the secondary-side full-bridge frequency converter; a voltage spike suppression circuit, including D1, D3, D2, and D4; the input terminal of the full-bridge circuit is connected in parallel with the secondary winding of the high-frequency transformer, and the output terminal of the full-bridge circuit is connected to a DC power supply.

This invention discloses an anti-interference economic relay and its operating method, including a relay coil, armature, iron core, contacts, and an anti-interference module. The anti-interference module is a resistor-capacitor (RC) absorption circuit, which consists of a resistor and a capacitor connected in series. The anti-interference module is connected in parallel with the relay coil, with one end connected to the first terminal of the relay coil and the other end connected to the second terminal. When the current in the relay coil is cut off, the RC absorption circuit provides a release path for the reverse induced electromotive force generated by the relay coil, absorbing and dissipating its energy and suppressing voltage spikes. By effectively suppressing the induced voltage across the relay coil, this invention can eliminate malfunctions caused by the induced voltage at the source, thereby ensuring the reliable operation of the relay and improving the stability of the entire control system.

The invention provides a multi-stage capacitor and power supply management power failure protection method and related equipment. The method comprises the steps of performing parameter extraction and confidence evaluation on a target load system to construct a system electrical parameter set, performing energy demand analysis on the system electrical parameter set to obtain critical energy demand data, and performing graded capacity planning according to multi-stage standby energy network data and the critical energy demand data to generate a standby power supply configuration strategy, when power failure protection is triggered, soft start switching and voltage spike suppression are carried out according to a system electrical parameter set and a standby power supply configuration strategy to generate a power failure switching control strategy set, and data preservation task planning is carried out on the power failure switching control strategy set according to hardware real-time task hierarchical data to generate a hardware task scheduling strategy. According to the invention, the hierarchical planning of the multi-stage standby energy, the smooth switching of soft start and peak suppression and the security planning of the hardware task hierarchical data realize reliable power-down maintenance and integrity guarantee of the key load and the key data.

This invention relates to the field of power electronics technology and discloses a simulation-optimized thyristor RC snubber method and circuit. The method includes: building a precise physical model containing stray parameters in a simulation environment; first, simulating and obtaining turn-off voltage spikes and dv / dt data without the snubber circuit connected; then, connecting an RC network and performing simulation comparisons with multiple sets of parameters for the resistor and capacitor; selecting the optimal RC parameters based on voltage suppression effect, dv / dt limitation, and resistor power consumption, and finally determining the device model. This invention overcomes the coarseness of traditional empirical formulas and the inefficiency of trial and error methods, offering advantages such as high design accuracy, intuitive process, and outstanding efficiency. It effectively avoids problems of conservative parameters or insufficient protection, achieving the best balance between cost, size, and performance while ensuring the safe operation of the thyristor. It is applicable to thyristor protection design in various power electronic systems; it quickly selects the optimal parameter combination that meets the requirements of voltage suppression and dv / dt limitation, shortening the product development cycle.

This invention proposes a voltage spike protection circuit, protection method, and application for wireless power transfer inverters, belonging to the field of wireless power transfer technology. It addresses the problems of existing wireless power transfer systems easily generating voltage spikes under special operating conditions, leading to increased device stress, and the lack of voltage spike protection functionality in inverters. The protection circuit includes: a high-frequency differential sampling module, a high-speed comparison module, a physical reset button, an optocoupler isolation module, a high-speed digital controller, and a single-ended drive module. The proposed protection circuit can effectively detect voltage spikes and combines hardware and software triggering to achieve timely protection, ensuring equipment safety. The protection circuit has an implementation path composed of purely analog circuits, with a short overall response time and reliable triggering, filling a functional gap in inverters.

The application discloses a kind of adaptive soft turn-off circuits of power switch device, it is related to electronic circuit technical field, including turn-off control module, detection module, energy storage delay module and soft turn-off execution module, detection module and energy storage delay module are connected between the drain and source of power switch device after series connection, detection module, energy storage delay module and power switch device form drain-source loop, when the comparison result of drain-source voltage in the turn-off process of power switch device and preset safety threshold controls energy storage delay module to store energy or discharge, according to the resistance value of soft turn-off resistance in the gate of power switch device that the resistance value of soft turn-off resistance in the gate of power switch device is adjusted dynamically according to energy storage or discharge, adjust the turn-off speed of power switch device. By energy storage, the resistance value of soft turn-off resistance in the gate of power switch device is dynamically adjusted by control signal, slow down the turn-off speed of power switch device, to suppress voltage spike.

A spiking neural network (SNN) system is disclosed having spiking neurons associated with clause values associated with a satisfiability (SAT) problem. Each spiking neuron generates a voltage spike when on input voltage applied to each spiking neuron is increased above a spiking voltage threshold. The input voltage that is increased above the spiking voltage threshold is indicative that the corresponding clause value is satisfied. A controller applies the clause grid that includes clause values to a literal grid that includes literal values. The controller generates the input voltage that is applied to each spiking neuron based on each corresponding clause value associated with each spiking neuron that is applied to the literal values. The controller determines that each clause value is satisfied when the corresponding spiking neuron generates the voltage spike and that each clause value is unsatisfied when the corresponding spiking neuron fails to generate the voltage spike.

Electrification device for an electric dust collector (1000) comprising an electrification module (1100, 3100) for generating ions in flowing air, wherein the electrification module (1100, 3100) comprises: a high-voltage peak (1130, 3130) having at least one discharge peak (1131) configured to emit the ions in a direction opposite to a flow direction of the air; a conductive plate (1120, 3120) arranged around the discharge tip (1131) and configured to generate an electrical potential difference to the discharge tip (1131) of the high voltage peak (1130, 3130); a lower frame (1140, 3140) that mounts the conductive plate (1120, 3120) and the high-voltage peak (1130, 3130); and an upper frame (1100, 3110) coupled to the lower frame (1140, 3140), wherein the upper frame (1100, 3110) covers the conductive plate (1120, 3120) and the high voltage peak (1130, 3130) so that the discharge peak (1131) is exposed to the outside; characterized by the fact that the upper frame (1100, 3110) has an upper outer frame (1111) which provides a lower frame coupling part for coupling with the lower frame (1140, 3140), and an upper inner frame (1112) which is arranged inside the upper outer frame (1111), wherein the lower frame (1140, 3140) provides a coupling hook (1141a) which corresponds to the lower frame coupling part.

The invention discloses a bidirectional DC-DC converter topological structure which comprises a coupling inductor unit, three power switch tubes, a low-voltage side filter capacitor, a high-voltage side filter capacitor and an auxiliary resonance branch. The coupling inductance unit comprises a primary winding and a secondary winding, and mutual inductance exists between the primary winding and the secondary winding; the low-voltage side filter capacitor is connected in parallel to two ends of the low-voltage port; the high-voltage side filter capacitor is connected in parallel with two ends of the high-voltage port; the auxiliary resonance branch comprises a resonance damping resistor and a resonance capacitor. The improved topological structure provided by the invention can restrain oscillating circulating current, eliminate voltage spikes and improve working stability and reliability.

The application provides a power grid voltage spike test system based on dynamic triggering, which realizes reliable capture and cause analysis of spikes through dynamic triggering threshold and device action time synchronization technology. The test system comprises a signal conditioning module, an analog-digital conversion module, a multi-source synchronous acquisition module, a cause analysis engine and a dynamic triggering module. Dynamic triggering conditions are set in the dynamic triggering module, the main characteristics of the power grid voltage spikes meeting the dynamic triggering conditions are matched with the main characteristics of the power grid voltage spikes preexisting in the rule base in the cause analysis engine, and the power grid voltage spike signals caused by device action are identified by checking the device action information and the power grid voltage spike timestamp.

The invention provides a battery unit voltage difference detection circuit and method for a battery monitoring chip, which can be applied to the technical field of batteries. The detection circuit comprises a multiplexer which is used for outputting a voltage signal of a first battery unit in a battery unit module in a first half period of a first control clock signal and outputting a voltage signal of a second battery unit in the battery unit module in a second half period of the first control clock signal so as to output a voltage square wave signal; the level shifter is used for separating a differential mode voltage and a common mode voltage in the voltage square wave signal to suppress interference of the common mode voltage and outputting a differential mode voltage square wave signal; the voltage peak blocking unit is used for suppressing voltage peak interference and outputting effective square wave signals in the differential mode voltage square wave signals; and the square wave demodulation amplifier module is used for carrying out fully differential chopping demodulation processing on the effective square wave signal to obtain a detection signal for representing the voltage difference of the battery unit.

The invention belongs to the technical field of DC-DC boost, and relates to a high-efficiency boost converter, a control method thereof and application of the high-efficiency boost converter in a photovoltaic or fuel cell power generation system. The converter is composed of two inductors, three switching tubes, six capacitors, six diodes and a current-limiting resistor, automatic current sharing of the input inductors can be achieved, input current ripples are small, the voltage gain reaches 6 / (1-D), the voltage stress of the switching tubes is Uo / 6, the voltage stress of the diodes is Uo / 3, current spikes and voltage spikes do not exist, and therefore the converter can be applied to large-scale production. And soft start and switch tube common-ground driving can be realized.

The application provides a battery cell voltage difference detection circuit and method for a battery monitoring chip, which can be applied to the technical field of batteries. The detection circuit comprises a multiplexer, which is used for outputting a voltage signal of a first battery cell in a battery cell module in a first half cycle of a first control clock signal and outputting a voltage signal of a second battery cell in the battery cell module in a second half cycle of the first control clock signal, so as to output a voltage square wave signal; a level shifter, which is used for separating a differential mode voltage and a common mode voltage in the voltage square wave signal, so as to suppress common mode voltage interference and output a differential mode voltage square wave signal; a voltage spike blocking unit, which is used for suppressing voltage spike interference and outputting an effective square wave signal in the differential mode voltage square wave signal; and a square wave demodulation amplifier module, which is used for performing full differential chopping demodulation processing on the effective square wave signal, so as to obtain a detection signal for representing a battery cell voltage difference.

A multi-phase switched capacitor converter is disclosed for converting a first voltage into a second voltage, or vice versa. The converter includes two sub-converters connected in parallel between an input voltage and an output voltage. Each sub-converter comprises a flying capacitor and a plurality of switches. Power conversion is performed by periodically switching the electrical connection between the flying capacitor and the voltage sources, between a first switching phase and a second switching phase. The two sub-converters alternately switch between a first system state and a second system state in a periodic manner. During the transition between the first and second system states, an overlapping system state is inserted, wherein both sub-converters are simultaneously in the first switching phase, thereby ensuring continuous current flow and reducing voltage spikes.

A method for detecting the presence or absence of a magnetic measurement probe at a measurement initiation location within an electromagnetic coil of an ophthalmic instrument includes: applying a transient current pulse to the electromagnetic coil; detecting a back electromotive force voltage spike induced in the electromagnetic coil by the current pulse; evaluating the decay behavior of the back electromotive force voltage spike; and correlating the decay behavior of the back electromotive force voltage spike with the presence or absence of the measurement probe at the measurement initiation location.

The invention relates to a power supply module applied to a TFT (Thin Film Transistor) liquid crystal screen. The power module applied to the TFT liquid crystal screen comprises an input module, a voltage reduction module and an output module, the input module comprises a TVS tube D8, a resistor R45, a capacitor C63 and a capacitor C59, the first end of the TVS tube D8 is electrically connected with the first end of the resistor R45, the second end of the TVS tube D8 is electrically connected with the second end of the resistor R45, the first end of the capacitor C63 is electrically connected with the second end of the resistor R45, the second end of the capacitor C63 is grounded, and the voltage reduction module is connected with the output module. The first end of the capacitor C59 is electrically connected with the first end of the capacitor C63, and the second end of the capacitor C59 is electrically connected with the first end of the capacitor C63; the voltage reduction module is electrically connected with the first end of the capacitor C59; the output module is electrically connected with the voltage reduction module. According to the scheme provided by the invention, surge protection can be carried out on the input part of the DC-DC circuit, so that a DC-DC chip is prevented from being punctured by voltage spikes generated by fluctuations such as lightning stroke and sudden power failure.