38 results about "Resettable fuse" patented technology

The utility model provides a short-circuit protection circuit for a Type-C interface, and belongs to the technical field of short-circuit protection circuits. Comprising an interface module, an overvoltage and electromagnetic protection circuit and a switching circuit, the interface module, the overvoltage and electromagnetic protection circuit and the switching circuit are connected in series on the same power line and grounding line, and a common circuit and a standby circuit are arranged in the switching circuit and are both connected with the power line. According to the utility model, through the cooperation of the resettable fuse, the double-pole double-throw relay and other elements, the circuit can be rapidly switched so as to ensure that the interface can continue to work normally without maintenance when a short-circuit fault occurs, and through the synergistic effect of the gas discharge tube, the first transient suppression diode, the second transient suppression diode, the electrolytic capacitor and other elements, the short-circuit fault of the interface can be effectively prevented. The problems of overvoltage and electromagnetic interference during short circuit can be effectively relieved.

The utility model discloses a self-protection circuit suitable for an energy storage pre-charging loop. The cathode of an energy storage power supply is connected with a cathode relay K1, and the anode of the energy storage power supply is sequentially connected with a main loop fuse F1 and an anode relay K2; the pre-charging resettable fuse F2 is sequentially connected with a pre-charging relay K3, a pre-charging resistor R1 and an anti-reverse diode D2 in series, and a series circuit is connected to the two ends of the K2 in parallel; two ends of a control coil of the K3 are respectively connected with positive and negative electrodes of a diode D1; one end of the resistor R2 is connected with a control signal P1, and the other end of the resistor R2 is connected with the resistor R3 and the base electrode of the triode Q1; the collector electrode of the triode Q1 is connected with one end of a control coil of the pre-charging relay K3 and the positive electrode of the diode D1, and the emitter electrode is grounded; the negative electrode of the diode D1 and the other end of the control coil of the relay K3 are connected with a power supply VCC through S1. According to the utility model, the self-protection of the pre-charging circuit can be realized when the pre-charging circuit performs the pre-charging action and the external load is short-circuited.

The invention relates to the technical field of electrical control and circuit protection, and discloses an anti-overcurrent building controller which comprises a protection mechanism, a sealing mechanism is arranged on the front face of the protection mechanism, a control mechanism is arranged at the bottom of the protection mechanism, and the outer side of the control mechanism is fixedly connected with the interior of the protection mechanism. And the outer side of the sealing mechanism is inserted into the protection mechanism. According to the building controller with the anti-overcurrent design, the reliability and redundancy of overcurrent protection are improved, when a certain resettable fuse breaks down, other resettable fuses can still work normally, accurate protection of a circuit is achieved, damage to the service life of the circuit is reduced, early warning information is sent to a monitoring center and wireless communication equipment through the controller, and the safety of the monitoring center and the wireless communication equipment is improved. And the safety of the equipment is remotely processed, so that a worker can conveniently manage a plurality of building controllers in a centralized manner, know the operation state of the equipment in real time and perform unified scheduling and management, and maintenance personnel do not need to run around to check the situation.

The utility model relates to the technical field of industrial automation, in particular to a digital measurement and control instrument of a mechanical switch closing resistor. Comprising a power supply adjusting circuit module which is provided with a 24VDC power supply input end, and the 24VDC power supply input end is connected with a resettable fuse F1 through an anti-reverse diode D2 and then is connected with the input end of a switching power supply voltage adjusting chip U1. According to the utility model, the dynamic constant current source controlled by the high-precision DAC and the built-in 24b-it analog-to-digital converter of the NSA2860 chip are integrated, so that a multi-mode excitation current regulation and control mechanism is constructed. Based on real-time voltage drop signal analysis of an MCU, the system automatically triggers a relay to switch an excitation loop to a precise sampling resistor for online calibration, obtains a precise current value under current DAC output and stores calibration parameters, and cooperative control of nanoampere-level current resolution and milliohm-level resistance measurement is achieved.

1. Name of the designed product: solid state relay (resettable fuse). 2. Use of the designed product: used in control circuit. 3. Design points of the designed product: in shape. 4. Picture or photo that best shows the design points: front view.

The invention discloses an electromagnetic valve open and short circuit detection system for energy storage, and the system comprises an input voltage detection module which is used for detecting the power supply voltage of an electromagnetic valve; the current detection module is used for detecting the current when the electromagnetic valve works; the voltage detection module is responsible for detecting post-stage voltage of the resettable fuse; the differential voltage detection module is used for detecting a voltage difference value when the electromagnetic valve is used; the output control module can control the on-off of the electromagnetic valve; and the single-chip microcomputer micro-control module can collect detection values of the input voltage detection module, the current detection module, the voltage detection module and the differential voltage detection module and regulate and control the output control module according to the detection values. According to the system, the open circuit state and the short circuit state of the electromagnetic valve can be detected at the same time, the whole scene where 24V voltage is not provided and 24V driving voltage is provided is covered, the problem that a traditional detection circuit is single in function is solved, and comprehensive monitoring of the working state of the electromagnetic valve is achieved by accurately collecting voltage signals of all modules.

The utility model relates to the technical field of electronic parts, in particular to an intelligent protection circuit for an automobile windscreen wiper based on a PPTC (Polymeric Positive Temperature Coefficient) resettable fuse. Comprising a wiper motor control circuit, a wiper motor, a gear switch and a protection circuit, the wiper motor control circuit controls the wiper motor through the gear switch, and the protection circuit is connected with the wiper motor control circuit, the wiper motor and the gear switch. The protection circuit comprises a PPTC resettable fuse overcurrent protection circuit, an RV voltage dependent resistor overvoltage protection circuit, isolation filter inductors L1 and L2, a capacitor C1 and a capacitor C2. According to the utility model, the number of components is small, the occupied volume is small, the cost is lower, the reliability is higher, related potential safety hazards or problems can be well solved, the repair and maintenance become simpler, and the market competitive advantage can be obviously improved.

The utility model relates to the technical field of electronics, in particular to an intelligent magnetic pulse therapeutic apparatus circuit based on a PPTC resettable fuse. A second resettable fuse PPTC and a first resettable fuse PPTC are respectively connected in series between a switching voltage-stabilized power supply of a pulse therapeutic instrument main control computer and a mains supply and between a power conversion controller and the mains supply, a resettable fuse PPTC is connected in series between an MOS tube and an overvoltage protection device, and a magnetic pulse coil is controlled through a pulse output gear regulator. According to the utility model, not only can a series of problems of more components, large occupied space, high failure rate and the like in the traditional scheme be solved, especially current-limiting protection of short circuit be realized, but also artificial and non-artificial short circuit protection can be completed on a circuit system, so that the conditions of circuit burnout and serious fire caused by short circuit can be avoided.

The present invention discloses a charging pile power supply circuit for a TBOX power supply. The circuit includes an anti-reverse polarity diode D85, an anti-reverse polarity diode D86, a resettable fuse F5, a transient suppressor diode D87, an anti-reverse polarity diode D88, and an output capacitor C12. The positive and negative interfaces of the charging input of the charging pile are respectively connected to one input end of the resettable fuse F5 after passing through D85 and D86. The other end of the resettable fuse F5 is connected to the positive electrode of D88, the negative electrode of D88 is connected to one end of the capacitor C12, and the other end of the capacitor C12 is grounded. Power supply output terminals are respectively drawn from both ends of the capacitor C12, and the power supply output terminals are used to connect to the TBOX. A terminal is drawn between the resettable fuse F5 and D88 to connect to the negative electrode of the transient suppressor diode D87, and the positive electrode of the transient suppressor diode D87 is grounded. The circuit structure of the present invention is simple, and it can achieve normal power supply when the charging pile has abnormal high voltage fluctuations. After the circuit is damaged, it can detect faults immediately, give an alarm reminder, and promptly discover hardware faults in the circuit.

The invention relates to a charging circuit of a shared communication bus, and aims to solve the problem that a traditional charging mode needs to occupy extra cable space and is limited in charging power. A charging function is realized by multiplexing a communication bus, and the device comprises a solid-state relay isolation module, a circuit voltage division module and a power supply access module. Wherein the solid-state relay isolation module detects bus voltage in real time, and when the voltage exceeds a threshold value (greater than or equal to 20V), the solid-state relay isolation module is automatically switched to a charging mode and isolates the communication chip; the circuit voltage division module accurately detects voltage through voltage division resistors R3, R4 and R5, and the resistance value of the circuit voltage division module meets the relational expressions # imgabs0 # and # imgabs1 # to ensure reliable switching between a communication mode and a charging mode; the power supply access module adopts back-to-back NMOS switches (VT1-VT4) and a photoelectric coupling driver, and bus high voltage is safely led into a power supply network. The communication chip is protected from transient high-voltage impact through the clamping diode and the resettable fuse, meanwhile, a special charging cable is omitted, the proportion of a charging circuit is remarkably reduced, and the charging power is improved.

The utility model provides a DC power supply input protection circuit, which is characterized in that the circuit comprises a self-recovery fuse F1 and a second diode D2, the first end of the self-recovery fuse F1 is electrically connected with a power supply input end, and the second end of the self-recovery fuse F1 is electrically connected with a power supply output end; the anode of the second diode D2 is grounded, and the cathode of the second diode D2 is electrically connected with the second end of the resettable fuse F1. When the positive electrode and the negative electrode of the input power supply are reversely connected, the second diode D2 is conducted and forms a loop with the resettable fuse F1 and the power supply input end, the resettable fuse automatically disconnects the circuit due to large current, and the effect of protecting a post-stage circuit due to reverse connection of the positive electrode and the negative electrode is achieved. Therefore, the utility model provides a hardware architecture, and safety protection can be carried out on reverse insertion of the positive electrode and the negative electrode of the direct-current power supply of the charging circuit through circuit integrated design.

The invention discloses a battery management circuit module and mobile power supply equipment. The battery management circuit module comprises an external connection port, a battery connection port, a bidirectional power conversion unit, a charging and discharging switch unit, a non-resettable fusing unit and an intelligent management unit. Wherein the bidirectional power conversion unit is used for performing bidirectional voltage conversion between an external connection port and a power bus node; the charging and discharging switch unit and the non-resettable fusing unit are connected in series between the power bus node and the positive electrode interface of the battery connection port to form a high-side protection framework; the intelligent management unit is used for calculating the electric quantity state based on an impedance tracking algorithm and outputting a driving signal to the non-resettable fusing unit when a fault is detected. According to the invention, a high-side protection architecture is adopted to ensure stable communication, and a fault loop is physically cut off in combination with an active fusing mechanism, so that the safety and reliability of high-power fast charging are improved.

An intrinsically safe battery assembly includes a battery pack including at least one battery and a protection circuit connected in series with the battery pack. The protection circuit includes the following elements connected in series: at least one diode configured to prevent the battery pack from being reversely charged, at least one current limiting resistor configured to provide short circuit protection and a resettable fuse configured to provide over current protection.

The utility model discloses an electric energy meter communication module, comprising a control side circuit having a power supply end and a reference ground end; the isolation side circuit is provided with a power supply end and a reference ground end and is used for connecting a bus; a first optocoupler; a second optocoupler; a third optocoupler; a transceiver; a first transistor; the second transistor is arranged on the isolation side circuit, the base electrode of the second transistor is connected with the output end of the second optocoupler, and the collector electrode of the second transistor is connected with the sending input end of the transceiver; the bidirectional transient voltage suppressor is connected to the differential signal input / output end of the transceiver; and the self-recovery fuse is connected in series between the differential signal input / output end of the transceiver and the bus. The electric energy meter communication module has the following beneficial effects that the electric energy meter communication module has the characteristics of high anti-interference capability, high reliability, high safety and convenience in maintenance.

The utility model discloses an overvoltage protection and sensing circuit and an analog input detection device. Relates to the technical field of analog quantity detection. According to the scheme, on the basis of a traditional analog quantity input detection technology, the structure is improved; the self-recovery fuse F1 and the transient suppression diode TVS1 are utilized to generate voltage difference at two ends of the self-recovery fuse during overvoltage, and the PMOS tube Q1 is switched on when negative voltage is generated at two ends of the G pole and the S pole by utilizing the conduction characteristic of the PMOS tube Q1. The two are ingeniously combined, that is, the voltage difference generated at the two ends of the resettable fuse is applied to the G pole and the S pole of the PMOS tube Q1 to sense overvoltage; therefore, the purposes of simplifying devices and saving material cost are achieved, the current consumption of analog signals is reduced, the sensing circuit almost has no leakage current in a normal state, and the influence on the signals is reduced.

The utility model relates to the technical field of electronic circuits, in particular to an intelligent card swiping scanning and reading equipment protection circuit based on a PPTC resettable fuse. A voltage input end of the power conversion circuit is connected with a PPTC1 and a TVS1 which are connected in series during DC power supply, a voltage input end of the power conversion circuit is connected with a PPTC2 and a TVS2 which are connected in series during lithium battery power supply, a PPTC3 is connected between the MOS tube Q1 and the intelligent card induction and identification circuit, and a PPTC4 and a PPTC5 are connected between the power conversion circuit and the data read-write storage and transmission circuit. The card swiping device is small in size, low in cost and high in reliability, and can be applied to all card swiping related product equipment in various fields of buses, hospitals, shopping malls, supermarkets and the like.

The utility model discloses a low-voltage power supply input protection circuit, which comprises a power supply input end, a voltage stabilizing diode, a resettable fuse, a filter capacitor and a Schottky diode, the voltage stabilizing diode is connected between the power supply input ends and is used for overvoltage protection; the resettable fuse is connected in series with the positive electrode of a power supply and is used for overcurrent protection; the filter capacitor is connected in parallel with a power supply input end and is used for filtering high-frequency noise and stabilizing power supply input voltage; and the Schottky diode is connected in series with the power supply input end and is used for polarity protection. The low-voltage power supply input protection circuit can effectively improve the reliability and stability of power supply input, protect circuit elements from being influenced by overvoltage, overcurrent and reverse connection, and ensure the stable operation of a system.

The utility model relates to the technical field of resettable fuses, and discloses a combined resettable fuse which comprises a fuse body, the outer wall of the fuse body is fixedly connected with pins, the outer wall of the fuse body is provided with a connecting shell, the outer wall of the connecting shell is connected with an extension shell in a sliding mode, the inner wall of the extension shell is provided with a connecting assembly, and the connecting assembly is fixedly connected with the pins. A through hole is formed in the connecting shell in a penetrating mode, a limiting groove is formed in the connecting shell, and a fixing assembly is installed on the outer wall of the connecting shell. The connecting assembly comprises a limiting protruding block. According to the utility model, the fuse body is placed in the connecting shell and is fixed through the elasticity of the connecting shell; the other connecting shell is placed on the side of the extension shell, the extension shell slides to enable the limiting blocks to slide in the sliding grooves, and then the clamping blocks are clamped into the positioning grooves, so that a plurality of fuse bodies are quickly combined for use, the operation is simple and convenient, and the practicability and adaptability of the fuse in different scenes are improved.

The invention discloses a high-power intelligent seedling raising machine master control circuit based on ESP32-S3 chip design, which comprises a master control circuit based on ESP32-S3-WROOM as a core design, a voice interaction circuit composed of a power amplifier circuit based on MAX98357 as a core design and a microphone circuit based on EV-INMP441 as a core design, and an expansion circuit based on MCP23017 as a core. The high-power power supply circuit consists of a high-power power supply adjusting circuit taking JWH6344 as a core and a voltage stabilizing circuit taking AMS117 as a core, and the direct external equipment circuit consists of a key downloading circuit, a sensor serial port downloading interface circuit, a WS2812 light bar interface circuit and a steering engine interface circuit. The high-power power supply interface circuit is composed of an XT60 interface circuit and a 15A resettable fuse circuit, the motor control circuit, the fan control circuit, the heating rod control circuit and the semiconductor refrigeration control circuit are designed based on an optocoupler control circuit, and the humidifier control circuit, the water pump control circuit and the reserved interface circuit are designed based on an mos tube control circuit.

This invention discloses a voltage and current limiting circuit for transformer output and a power supply device for explosion-proof floodlights, comprising: multiple voltage and current limiting modules connected in sequence, each module including a diode, a resettable fuse, a thyristor, and a resistor; this voltage and current limiting circuit can effectively limit the voltage and current jumps of the high-frequency pulse current output by the transformer, ensuring the stability and safety of the subsequent circuits, and its design is simple and low-cost, fully meeting the requirements of explosion-proof standards. Furthermore, due to the use of resettable fuses and thyristors, the voltage and current limiting circuit can maintain stable performance even under long-term high-load operation, without performance degradation or damage due to temperature rise, thereby greatly improving the overall safety and stability of the explosion-proof floodlight power supply device.

The utility model discloses a resettable fuse device, and particularly relates to the technical field of resettable fuses, which comprises a bottom protective sleeve, a top protective sleeve is arranged on the outer side of the upper end of the bottom protective sleeve, a limiting support block is arranged on the end face of the lower side of the bottom protective sleeve, and a concave mounting groove is formed in one side of the upper end of the bottom protective sleeve. A convex limiting protruding block is arranged on the outer end face of the concave mounting groove, a limiting clamping plate is arranged on one side of the lower end of the top protection sleeve, and a concave limiting clamping groove is formed in the inner side end face of the limiting clamping plate. When the self-recovery fuse is actually used, the self-recovery fuse main body can be conveniently installed under the corresponding arrangement state of the concave groove, the strip-shaped limiting groove, the self-recovery fuse main body, the fuse pins and the beeswax sealing block, and meanwhile the self-recovery fuse main body can be conveniently installed under the adaptive state of the concave limiting clamping groove and the convex limiting convex block. And the closing stability of the bottom protection sleeve and the top protection sleeve can be effectively improved, so that the resettable fuse main body can be conveniently protected.

The utility model provides a weather-resistant PPTC resettable fuse. The weather-resistant PPTC resettable fuse comprises a packaging frame body and a chip main body, the packaging frame body is configured into a regular rectangular structure; the chip main body is made of a positive temperature coefficient composite material; the positive temperature coefficient composite material at least comprises polyvinylidene fluoride and conductive particles; the chip main body comprises a first chip layer and a second chip layer; the first chip layer is located on the upper layer and the right side of the first chip layer is hollowed to form a first abdicating area used for avoiding the right electrode. The second chip layer is located on the lower layer and the left side of the second chip layer is hollowed to form a second abdicating area used for avoiding the left electrode. A hollow through space is formed in the middle area of the packaging frame body, and the first chip layer and the second chip layer are adaptively embedded in the through space in a press fit manner; compared with the prior art, a simpler packaging frame body is adopted, production and installation are facilitated, the overall mechanical strength and stability can be effectively improved, and the rectangular packaging frame body is beneficial to ensuring reasonable layout of the PPTC chip and facilitating electrical connection and heat dissipation design.

The utility model discloses a circuit device with over-current protection and alarm functions, which relates to the technical field of circuits and comprises a live wire L, a null line N and the following branches connected between the live wire L and the null line N. The main branch is sequentially connected with a diode, a first resettable fuse and an electric appliance in series. And one end of the first branch is connected to a node between the first resettable fuse and the diode in the main branch. According to the utility model, by arranging the first resettable fuse and the second resettable fuse, overcurrent protection of a circuit is realized, and an electric appliance is prevented from being damaged by overcurrent; the diode controls the current flow direction, and the circuit safety is improved; a divider resistor and a dropping resistor ensure that the voltage of each branch meets the working requirement of the element; the alarm timely feeds back the abnormal state of the circuit; the capacitor stabilizes voltage and reduces interference; the whole circuit is reasonable in structural design and complete in function, and reliability, safety and stability of a circuit system are improved.

An intrinsically safe battery assembly (1) comprising a battery pack (U) consisting of at least one battery (U1, U2, U3, U4) and a protection circuit (C) connected in series with the battery pack (U). The protection circuit (C) includes a diode (D) to prevent reverse charging of the battery pack (U), a current-limiting resistor (R) to provide short-circuit protection, and a resettable fuse (F) to provide overcurrent protection. Additionally, a single-point lubrication device (100) is provided, comprising a reservoir (20) for storing a lubricant and a power compartment (10) for housing power components. The reservoir (20) and the power compartment (10) are suitable for being detachably assembled as a single unit.The power components include an electric motor (M) and the intrinsically safe battery assembly (1) described above for supplying energy to the electric motor. The electric motor (M) is used to drive a pump mechanism (P) to force the lubricant in the reservoir (20) out of an oil outlet (21).

The utility model relates to the technical field of display screen control, and discloses a circuit of a display screen control circuit board, which is characterized in that all layers of DC 12V input seats (a wire holder J1 and a wire holder J27) of a power supply input circuit are prohibited from being coated with ground copper during copper coating of a PCB (Printed Circuit Board), the distance is more than 1mm, a main power supply is separated from other circuits, large-area burning of a mainboard is avoided, and the service life of the mainboard is prolonged. The negative electrode of the DC base is grounded to the main ground only through two packaged R1210 / 0R resistors, the effects of EMI radiation and ESD protection are achieved, the positive electrode of the DC base passes through a packaged R1210 / 0R resistor and then a resettable fuse, the effects of overvoltage and overcurrent protection, EMI radiation and ESD protection are achieved, and then the risk that a display screen is burnt out in the testing or running process is reduced; through the design of the plum-blossom-shaped packaging seat, after solder paste is applied, the packaging seat protrudes by 0.2 mm, the packaging seat can be fully grounded, heat dissipation, ESD protection and EMI radiation protection are facilitated, screw slipping is prevented, and a PCB copper sheet is prevented from falling off during screw driving.

The utility model relates to the technical field of electronics, in particular to a wide time delay power supply protection circuit based on PPTC resettable fuses, which comprises a wide time delay power supply and a load circuit, and corresponding resettable fuses and MOS (Metal Oxide Semiconductor) tubes are connected in series between a driving control circuit and each motor. A first resettable fuse and a second resettable fuse are welded on a circuit board of the wide delay power supply, and the drive control circuit comprises a power supply module, a sampling circuit module, a threshold analysis module and an execution protection module. According to the utility model, the on-off control under different currents is realized by adjusting the overcurrent protection circuit, the application is flexible and convenient, and a good overcurrent protection function is provided for electronic equipment needing overcurrent protection.

The invention discloses a battery box which comprises a box body, a battery mounting groove is formed in the box body and used for mounting a plurality of batteries, and conductive elastic pieces are arranged on the two sides of the battery mounting groove so that the batteries can be connected in series to supply power. A control switch, a control circuit board and a power connection socket are arranged in the box body, the control circuit board comprises a single chip microcomputer, an AD sampling module is arranged in the single chip microcomputer and used for collecting the voltage of the battery pack in real time, and a turn-off signal is output when the voltage is lower than 3.6 V; 3.6 V accurate threshold detection is realized through the single chip microcomputer, power supply is automatically cut off, over discharge and liquid leakage of the battery are effectively avoided, and the service life of the battery is prolonged; rechargeable management: the battery is supported to be independently taken out for charging, and power supply is automatically recovered after charging, so that the use cost is reduced, and the portability and the economical efficiency are improved; and multiple safety protection: integrating overcurrent protection (resettable fuse), low-voltage protection (triode electronic switch) and anti-reverse protection (diode), thereby comprehensively improving the safety and stability of the circuit.

The utility model discloses a regulator W terminal design circuit adapted to a 4V constant electric instrument panel, which comprises an HS-P terminal, an HS-W terminal and an HS-L terminal, the HS-P terminal is connected with one end of a resistor R34, one end of a resistor R35 and one end of a resettable fuse L2, the resistor R34, the resistor R35 and the resettable fuse L2 are connected in parallel, and the other end of the resettable fuse L2 is connected with the HS-W terminal. The other end of the resistor R34, the other end of the resistor R35 and the other end of the resettable fuse L2 are connected with a resistor R31 and a capacitor C27 and are connected to an HS-W terminal, discrete electronic materials are used for designing circuits, different instrument panel circuits can be matched, portability is high, and application is flexible. The circuit design is ingenious, the situation that a P-end phase signal is pulled down all the time when an automobile is started and stopped is avoided, and the problems that an instrument panel is mistakenly recognized and a pointer swings disorderly due to sudden speed change of a generator in the driving process of the automobile are solved. The development period is shortened, the development cost is reduced, and the market competitiveness is improved.

The utility model is suitable for the technical field of display, and provides a circuit board structure, an LED display unit and an LED display screen, the circuit board structure comprises a circuit board body and a temperature detection circuit, the temperature detection circuit comprises a plurality of resettable fuses which are connected in series, and when the temperature of any resettable fuse in the area where the resettable fuse is located is abnormal, the resettable fuse is switched on. The temperature detection circuit outputs a first signal; and the temperature abnormity processing module is electrically connected with the temperature detection circuit, the temperature abnormity processing circuit is used for outputting a first control signal when receiving the first signal, and the first control signal is used for controlling the power supply of the circuit board body to be switched off. According to the invention, the plurality of resettable fuses are arranged on the circuit board body, and the resettable fuses are connected in series to form the temperature detection circuit, so that the temperature detection circuit outputs the first signal to the temperature abnormality processing circuit to turn off the power supply when the temperature of any resettable fuse in the region where the resettable fuse is located is abnormal. Therefore, the circuit board cannot reach the firing temperature, and combustion is avoided.

The utility model relates to the technical field of fuses, and discloses a high-voltage surface-mounted PPTC resettable fuse which comprises a fuse body, the outer wall of the fuse body is fixedly connected with a first protective sleeve, the outer wall of the fuse body is fixedly connected with a second protective sleeve, the outer wall of the fuse body is provided with a heat dissipation assembly, and the heat dissipation assembly is fixedly connected with the protective sleeve. The heat dissipation assembly is used for dissipating heat of the fuse body; the heat dissipation assembly comprises a heat dissipation plate, one side of the heat dissipation plate is fixedly connected to the outer wall of the fuse body, the other side of the heat dissipation plate is fixedly connected with a plurality of heat dissipation fins, and the heat dissipation fins are evenly distributed on the other side of the heat dissipation plate in a linear array mode. According to the utility model, when the fuse body generates heat, the heat is conducted to the heat dissipation plate and then is transmitted to the heat dissipation fins, and the heat dissipation fins accelerate heat dissipation to the surrounding environment by increasing the contact area with air, so that the effect of effective heat dissipation of the fuse body is realized, and the stability of the fuse is improved.