CN219372020U

CN219372020U - Surge suppression circuit

Info

Publication number: CN219372020U
Application number: CN202320192489.1U
Authority: CN
Inventors: 彭丽娟
Original assignee: Guangdong Yingke Electronic Co ltd
Current assignee: Guangdong Yingke Electronic Co ltd
Priority date: 2023-02-09
Filing date: 2023-02-09
Publication date: 2023-07-18
Anticipated expiration: 2033-02-09

Abstract

The utility model relates to the technical field of circuits, in particular to a surge suppression circuit, which comprises a power input end, an NTC thermistor, a first diode, a direct-current voltage conversion chip and a power output end which are sequentially connected, wherein the anode of the first diode is connected with the NTC thermistor, and the cathode of the first diode is connected with a power input pin of the direct-current voltage conversion chip; the NTC thermistor is used for absorbing surge voltage generated by the power input end and transmitting direct current input voltage accessed by the power input end to the direct current voltage conversion chip; the direct-current voltage conversion chip is used for converting the input voltage into a power supply voltage matched with a load and then transmitting the power supply voltage to the power supply output end; according to the utility model, the NTC thermistor is added at the input end of the power supply circuit, so that surge voltage can be restrained, and the rear-end device can be protected.

Description

Surge suppression circuit

Technical Field

The utility model relates to the technical field of circuits, in particular to a surge suppression circuit.

Background

In the hot plug process of electrical equipment such as a water purifier and the like through an input interface of a power circuit, surge voltage can be generated, and under the impact of the surge voltage, if the power circuit cannot completely suppress the surge, high voltage is continuously transmitted to the rear end of the power circuit, and the rear end device can be burnt out.

Disclosure of Invention

In order to solve the problems, the utility model provides a surge suppression circuit for suppressing surge voltage and protecting a back-end device.

In order to achieve the above object, the present utility model provides the following technical solutions:

the surge suppression circuit comprises a power input end, an NTC thermistor, a first diode, a direct-current voltage conversion chip and a power output end which are sequentially connected, wherein the anode of the first diode is connected with the NTC thermistor, and the cathode of the first diode is connected with a power input pin of the direct-current voltage conversion chip;

the NTC thermistor is used for absorbing surge voltage generated by the power input end and transmitting direct current input voltage accessed by the power input end to the direct current voltage conversion chip;

the direct-current voltage conversion chip is used for converting the input voltage into a power supply voltage matched with a load and transmitting the power supply voltage to the power supply output end.

Further, the power input end adopts a socket with two ports, one connecting terminal of the socket is connected with the NTC thermistor, the other connecting terminal is connected with a fuse, and the fuse is connected with the AC port of the direct-current voltage conversion chip.

Further, the first diode is a schottky diode.

Further, the surge suppression circuit further comprises a transient diode, wherein the cathode of the transient diode is connected with the cathode and the anode of the first diode and the output end of the fuse to be commonly grounded.

Further, the surge suppression circuit further comprises a first filter circuit, and the first filter circuit is used for filtering the power supply output by the first diode and outputting the filtered power supply to the direct-current voltage conversion chip.

Further, the surge suppression circuit further comprises an I-shaped inductor arranged between a power output pin of the direct-current voltage conversion chip and the power output end.

Further, the surge suppression circuit further comprises a discharge circuit connected with the power supply output end.

Further, the surge suppression circuit further comprises a second filter circuit, and the second filter circuit is used for filtering the power supply output by the direct-current voltage conversion chip and outputting the filtered power supply to the power supply output end.

Further, the surge suppression circuit further comprises a second switch circuit, one end of the second switch circuit is connected with a power output pin of the direct-current voltage conversion chip, and the other end of the second switch circuit is grounded.

Further, a feedback pin of the voltage conversion chip is connected with the power supply output end.

The beneficial effects of the utility model are as follows: the utility model provides a surge suppression circuit, which can suppress surge voltage and protect a back-end device by adding an NTC thermistor at the input end of a power supply circuit.

Drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions of the prior art, the drawings that are needed in the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present utility model, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic circuit diagram of a surge suppression circuit in an embodiment of the present utility model.

Detailed Description

Reference will now be made in detail to the present embodiments of the present utility model, examples of which are illustrated in the accompanying drawings, wherein the accompanying drawings are used to supplement the description of the written description so that one can intuitively and intuitively understand each technical feature and overall technical scheme of the present utility model, but not to limit the scope of the present utility model.

In the description of the present utility model, it should be understood that references to orientation descriptions such as upper, lower, front, rear, left, right, etc. are based on the orientation or positional relationship shown in the drawings, are merely for convenience of description of the present utility model and to simplify the description, and do not indicate or imply that the apparatus or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present utility model.

In the description of the present utility model, if there is a word description such as "a plurality" or the like, the meaning of a plurality is one or more, and the meaning of a plurality is two or more, and greater than, less than, exceeding, etc. are understood to not include the present number, and above, below, within, etc. are understood to include the present number.

In the description of the present utility model, unless explicitly defined otherwise, terms such as arrangement, installation, connection, etc. should be construed broadly and the specific meaning of the terms in the present utility model can be reasonably determined by a person skilled in the art in combination with the specific contents of the technical scheme.

In the surge suppressing circuit in the related art, surge voltage may damage the circuit and its components, and the degree of damage is closely related to the compressive strength of components in the circuit and to energy that can be converted in the circuit. Under the impact of surge voltage, the direct-current voltage conversion chip U1 (such as a DC-DC chip) cannot completely suppress the surge, when the generated surge voltage is continuously higher than the withstand voltage of the DC chip, the DC chip is easy to burn out, high voltage is continuously transmitted to the rear end of the circuit through the DC chip, the voltage output by the DC chip is continuously lifted, and the output voltage is abnormal, so that a rear-end device is burned out.

Based on the above, the utility model provides a surge suppression circuit, which suppresses surge voltage and protects a back-end device by adding an NTC thermistor NTC at the input end of a power supply circuit. The NTC thermistor NTC is a negative temperature coefficient resistor, and has the double characteristics of not only inhibiting overcurrent, but also surge characteristics, and can absorb and generate surge voltage, so that the rear-end device is protected from being damaged.

Referring to fig. 1, an embodiment of the present utility model provides a surge suppression circuit, including a power input terminal, an NTC thermistor NTC, a first diode D1, a dc voltage conversion chip U1, and a power output terminal Vout, which are sequentially connected; the anode of the first diode D1 is connected with the NTC thermistor NTC, and the cathode of the first diode D1 is connected with the power input pin of the direct-current voltage conversion chip U1;

the NTC thermistor NTC is used for absorbing surge voltage generated by the power input end and transmitting direct current input voltage accessed by the power input end to the direct current voltage conversion chip U1;

the direct-current voltage conversion chip U1 is used for converting the input voltage into a power supply voltage adapted to a load and transmitting the power supply voltage to the power supply output end Vout.

It should be noted that, in the process of hot plug of the power input end, surge voltage is generated, if the surge voltage is too high, the voltage input to the dc voltage conversion chip U1 exceeds the withstand voltage thereof, so as to burn out the dc voltage conversion chip U1; in the embodiment provided by the application, the NTC thermistor NTC can absorb surge voltage to protect devices such as a rear-end direct-current voltage conversion chip U1; in some embodiments, the input voltage connected to the power input terminal is dc 36V, the power supply voltage adapted to the load is dc 5V, and the dc voltage conversion chip U1 is configured to convert the input voltage 36V into 5V.

NTC (Negative Temperature Coefficient) thermistor, also known as negative temperature coefficient thermistor, is a type of sensor resistor whose resistance decreases with increasing temperature. The NTC thermistor NTC not only has the double characteristics of suppressing overcurrent and surge characteristics, but also can absorb and generate surge voltage, thereby protecting the rear-end device from being damaged. According to the NTC thermistor, the NTC thermistor is added at the input end, a complex circuit is not needed, the cost is too high, and the problem of too high surge voltage is solved ingeniously.

As a preferable mode of the foregoing embodiment, the power input end adopts a two-port socket CON, one of the connection terminals of the socket CON is connected to the NTC thermistor NTC, the other connection terminal is connected to a FUSE, and the FUSE is connected to the AC port of the dc voltage conversion chip U1.

It should be noted that, in the embodiment provided by the application, the power input end adopts the two-port socket CON, direct current is accessed through the socket CON, and the FUSE is connected to one connecting terminal of the socket CON, so that the overlarge current of devices such as the direct current voltage conversion chip U1 and the like provided at the rear end can be prevented, and a protection effect is achieved.

As a preferred embodiment of the foregoing disclosure, the first diode D1 is a schottky diode, one end of the NTC thermistor NTC is connected to one of the connection terminals of the socket CON, the anode of the first diode D1 is connected to the other end of the NTC thermistor NTC, and the cathode of the first diode D1 is connected to the power input pin of the dc voltage conversion chip U1.

As a preference of the above embodiment, the surge suppression circuit further includes a transient diode D2, where a cathode of the transient diode D2 is connected to the cathode and anode of the first diode D1 and an output terminal of the FUSE is commonly grounded.

It should be noted that in the embodiment provided in the present application, the transient diode D2 (Transient Voltage Suppressor, TVS) is a high-performance protection device in the form of a diode. The transient diode D2 is a high-performance protection device in the form of a diode. When the two poles of the transient diode D2 are impacted by reverse transient high energy, the high resistance between the two poles can be changed into low resistance at the speed of the order of magnitude of minus 12 seconds of 10, and the surge power of thousands of watts is absorbed, so that the voltage clamp between the two poles is positioned at a preset value, and the precise components in an electronic circuit are effectively protected from being damaged by various surge pulses.

As a preferable mode of the above embodiment, the surge suppression circuit further includes a first filter circuit, and the first filter circuit is configured to filter the power supply output by the first diode D1 and output the filtered power supply to the dc voltage conversion chip U1.

It should be noted that, in the embodiment provided by the present application, the first filter circuit includes a first electrolytic capacitor EC1 and a first capacitor C1, the positive electrode of the first electrolytic capacitor EC1, one end of the first capacitor C1 and the cathode of the transient diode D2 are commonly connected to the power input pin of the dc voltage conversion chip U1, one end of the FUSE is connected to another connection terminal of the socket CON, and the other end of the FUSE, the negative electrode of the first electrolytic capacitor EC1, the other end of the first capacitor C1, the anode of the transient diode D2 and the AC port of the dc voltage conversion chip U1 are commonly grounded. The first capacitor C1 adopts the patch capacitor, the first electrolytic capacitor EC1 filters low-frequency noise to realize voltage stabilization, the first capacitor C1 filters high-frequency noise, the first electrolytic capacitor EC1 and the first capacitor C1 are used in a combined and matched mode, noise in each frequency band in input voltage can be filtered, and the stability of the input voltage is improved.

As a preferred embodiment of the above-described embodiment, the surge suppression circuit further comprises an I-shaped inductor L1 arranged between a power output pin of the direct-current voltage conversion chip U1 and the power output end Vout.

It should be noted that, in the embodiment provided in this application, one end of the i-shaped inductor L1 is connected to the power output pin of the dc voltage conversion chip U1, and the other end of the i-shaped inductor L1 is connected to the power output terminal Vout.

The coil of the I-shaped inductor L1 is generally composed of a magnetic core or an iron core, a framework, a winding group, a shielding case, a packaging material and the like; the skeleton of the I-shaped inductor L1 is a winding bracket of a copper core coil. The i-inductor L1 is one of the properties of an electronic circuit or device, and refers to: when the current is changed, some fixed inductors or adjustable inductors (such as oscillating coils, choke coils and the like) with larger volumes are generated by the electromotive force resisting the current change due to electromagnetic induction, the commonly used I-shaped inductor L1 is regarded as a vertical version of the axial inductor, the application is convenient and similar to the axial inductor, but the commonly used I-shaped inductor L1 can have an inductance type with larger volume, and the current can be naturally improved to a certain extent; most of the materials are that enameled wires (or yarn covered wires) are directly wound on a framework, and then a magnetic core or a copper core, a magnetic core and the like are arranged in an inner cavity of the framework so as to improve the inductance. The framework is usually made of plastics, bakelite and ceramics, and can be made into different shapes according to actual needs. A small inductor (e.g., i-inductor L1) typically does not use a former, but rather directly winds an enameled wire around a core. The stability of the i-inductor L1 is very high, which is not provided by a common inductor, and the current passing through the circuit is relatively smooth, and the efficiency quotient is improved greatly. The main functions of the I-shaped inductor L1 in the embodiment of the application are screening new numbers, filtering noise, stabilizing current and controlling electromagnetic interference, and the I-shaped inductor L1 is an excellent choice for dealing with EMI, and meanwhile, has an energy storage function.

As a preference of the above embodiment, the surge suppressing circuit further includes a discharging circuit connected to the power supply output terminal Vout.

It should be noted that, in the embodiment provided in this application, the discharge circuit adopts the discharge resistor R1, one end of the discharge resistor R1 is connected to the power output terminal Vout, and the other end of the discharge resistor R1 is grounded, so as to play a role of discharging through the discharge resistor R1.

As a preferable mode of the foregoing embodiment, the surge suppression circuit further includes a second filter circuit, where the second filter circuit is configured to filter the power supply output by the dc voltage conversion chip U1 and output the filtered power supply to the power supply output terminal Vout.

It should be noted that, in the embodiment provided by the application, the second filter circuit includes second electrolytic capacitor EC2 and second electric capacity C2, the positive pole of second electrolytic capacitor EC2 with the one end of second electric capacity C2 is connected jointly power output Vout, and second electric capacity C2 adopts the paster electric capacity, and second electrolytic capacitor EC2 filters low frequency noise and realizes the steady voltage, and second electric capacity C2 filters high frequency noise, and the combination is supporting to use second electrolytic capacitor EC2 and second electric capacity C2, can filter each frequency channel noise in the output voltage, provides stable power supply voltage for the load.

As a preferable mode of the foregoing embodiment, the surge suppression circuit further includes a second switching circuit, one end of which is connected to the power output pin of the dc voltage conversion chip U1, and the other end of which is grounded.

It should be noted that, in the embodiment provided by the application, the second switch circuit is a second diode D3, the second diode is a schottky diode, the anode of the second diode D3 is grounded, and the cathode of the second diode D3 is connected to the power output pin of the dc voltage conversion chip U1. The schottky diode has the advantages of high switching frequency, reduced forward voltage, and the like.

As a preferable aspect of the foregoing embodiment, the feedback pin of the dc voltage conversion chip U1 is connected to the power output terminal Vout.

The embodiments described in the embodiments of the present utility model are for more clearly describing the technical solutions of the embodiments of the present utility model, and do not constitute a limitation on the technical solutions provided by the embodiments of the present utility model, and those skilled in the art can know that, with the evolution of technology and the appearance of new application scenarios, the technical solutions provided by the embodiments of the present utility model are equally applicable to similar technical problems.

It will be appreciated by persons skilled in the art that the embodiments of the utility model are not limited by the illustrations, and that more or fewer steps than those shown may be included, or certain steps may be combined, or different steps may be included.

The apparatus embodiments described above are merely illustrative, in that the circuitry illustrated as separate components may or may not be physically separate, i.e., may be located in one place, or may be distributed over multiple network circuits. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

Those of ordinary skill in the art will appreciate that all or some of the steps of the methods, systems, functional modules/circuits in the devices disclosed above may be implemented as software, firmware, hardware, and suitable combinations thereof.

The terms "first," "second," "third," "fourth," and the like in the description of the utility model and in the above figures, if any, are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments of the utility model described herein may be implemented in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or circuits is not necessarily limited to those steps or circuits that are expressly listed or inherent to such process, method, article, or apparatus.

It should be understood that in the present utility model, "at least one (item)" means one or more, and "a plurality" means two or more. "and/or" for describing the association relationship of the association object, the representation may have three relationships, for example, "a and/or B" may represent: only a, only B and both a and B are present, wherein a, B may be singular or plural. The character "/" generally indicates that the context-dependent object is an "or" relationship. "at least one of" or the like means any combination of these items, including any combination of single item(s) or plural items(s). For example, at least one (one) of a, b or c may represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", wherein a, b, c may be single or plural.

In the several embodiments provided by the present utility model, it should be understood that the disclosed apparatus and method may be implemented in other manners. For example, the above-described apparatus embodiments are merely illustrative, and for example, the above-described circuit division is merely a logical function division, and there may be other division manners in which a plurality of circuits or components may be combined or integrated into another system, or some features may be omitted, or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or circuits, which may be in electrical, mechanical or other form.

The circuits described above as separate components may or may not be physically separate, and components shown as circuits may or may not be physical circuits, i.e., may be located in one place, or may be distributed over multiple network circuits. Some or all of the circuits may be selected according to actual needs to achieve the purpose of the embodiment.

In addition, each functional circuit in each embodiment of the present utility model may be integrated in one processing circuit, or each circuit may exist alone physically, or two or more circuits may be integrated in one circuit. The integrated circuit may be implemented in hardware or in software functional circuits.

The preferred embodiments of the present utility model have been described above with reference to the accompanying drawings, and are not thereby limiting the scope of the claims of the embodiments of the present utility model. Any modifications, equivalent substitutions and improvements made by those skilled in the art without departing from the scope and spirit of the embodiments of the present utility model shall fall within the scope of the claims of the embodiments of the present utility model. While the present disclosure has been described in considerable detail and with particularity with respect to the several illustrated embodiments, it is not intended to be limited to any such detail or embodiments or any particular embodiment, but rather should be construed as providing broad interpretation of such claims by reference to the appended claims, taking into account the prior art to thereby effectively encompass the intended scope of the present disclosure. Furthermore, the foregoing description of the utility model has been presented in terms of embodiments foreseen by the inventor for the purpose of providing a enabling description for enabling the enabling description to be available, notwithstanding that insubstantial changes in the utility model, not presently foreseen, may nonetheless represent equivalents thereto.

Claims

1. The surge suppression circuit is characterized by comprising a power input end, an NTC thermistor, a first diode, a direct-current voltage conversion chip and a power output end which are sequentially connected, wherein the anode of the first diode is connected with the NTC thermistor, and the cathode of the first diode is connected with a power input pin of the direct-current voltage conversion chip;

2. The surge suppression circuit of claim 1, wherein the power input employs a two-port socket, one of the terminals of the socket being connected to the NTC thermistor and the other terminal being connected to a fuse, the fuse being connected to the AC port of the dc voltage conversion chip.

3. A surge suppression circuit according to claim 2, wherein the first diode is a schottky diode.

4. A surge suppression circuit according to claim 3, further comprising a transient diode having a cathode connected to the cathode and anode of the first diode and the output of the fuse being commonly grounded.

5. The surge suppression circuit of claim 4, further comprising a first filter circuit configured to filter the power output from the first diode and output the filtered power to the dc voltage conversion chip.

6. The surge suppression circuit of claim 2, further comprising an i-inductor disposed between a power output pin of the dc voltage conversion chip and the power output.

7. The surge suppression circuit of claim 6, further comprising a discharge circuit connected to the power supply output.

8. The surge suppression circuit according to claim 7, further comprising a second filter circuit, wherein the second filter circuit is configured to filter a power supply output by the dc voltage conversion chip and output the filtered power supply to the power supply output terminal.

9. The surge suppression circuit according to claim 8, further comprising a second switching circuit having one end connected to a power output pin of the dc voltage conversion chip and the other end grounded.

10. The surge suppression circuit of claim 9, wherein a feedback pin of the voltage conversion chip is connected to the power supply output.