CN213937861U - High-temperature high-voltage protection circuit and optical module - Google Patents

Abstract

The application discloses high temperature high pressure protection circuit and optical module, the source electrode and the input of MOS pipe in the high temperature high pressure protection circuit are connected, and the drain electrode is connected with the load. The first resistor, the second resistor and the third resistor control the switch of the first triode. The regulating circuit composed of the first resistor, the second resistor, the third resistor and the first triode regulates the base voltage of the second triode, the regulating circuit, the fourth resistor, the fifth resistor and the sixth resistor control the switch of the second triode, and the switch state of the second triode controls the switch of the MOS tube. Under the normal state, the first triode works in the amplification region, the second triode works in the saturation region, at the moment, the grid electrode of the MOS tube is at a low level, and the source electrode and the drain electrode of the MOS tube are conducted. According to the characteristics of the triodes, when the temperature rises or the voltage of the input end rises, the base voltage of the second triode is reduced, the second triode is in a cut-off state, the grid electrode of the MOS tube is in a high level, the MOS tube is disconnected, and high-temperature and high-voltage protection on the load is realized.

Description

High-temperature high-voltage protection circuit and optical module

Technical Field

The application relates to the technical field of communication, in particular to a high-temperature and high-voltage protection circuit and an optical module.

Background

Various current electronic products have requirements on the voltage of an input power supply, and once the voltage of the input power supply is too high, the chip can be damaged unrecoverably. In addition to the requirements on the voltage of the input power supply, there are also requirements on the operating temperature. Too high a temperature may also cause damage to the chip.

In the prior art, the overvoltage protection of voltage adopts a protection chip, whether protection is needed is judged by detecting the specific size of input voltage, and when the voltage exceeds a set threshold, the output is cut off, so that a back-end circuit is protected. Temperature protection generally utilizes temperature sensor to gather temperature data, transmits to the protection chip, and the chip disconnection output when the temperature is too high to protection back-end circuit.

The above protection structures all require additional devices to acquire voltage or temperature information, and the cost is relatively high.

SUMMERY OF THE UTILITY MODEL

The application provides a high-temperature high-voltage protection circuit, which realizes high-temperature high-voltage protection of electronic products.

In order to solve the technical problem, the embodiment of the application discloses the following technical scheme:

the embodiment of the application discloses high temperature high pressure protection circuit includes: the source electrode of the MOS tube is connected with the input end, and the drain electrode of the MOS tube is connected with the load;

one end of the sixth resistor is connected with the source electrode of the MOS tube, and the other end of the sixth resistor is connected with the grid electrode of the MOS tube;

a first resistor, the first end of which is connected with the input end;

a first end of the second resistor is connected with a second end of the first resistor, and the second end of the second resistor is grounded;

a first end of the third resistor is connected with the input end;

a first end of the fourth resistor is connected with a second end of the third resistor;

a first end of the fifth resistor is connected with a second end of the fourth resistor, and the second end of the fifth resistor is grounded;

a base electrode of the first triode is arranged between the first resistor and the second resistor, a collector electrode of the first triode is arranged between the third resistor and the fourth resistor, and an emitting electrode of the first triode is grounded;

and a base electrode of the second triode is arranged between the fourth resistor and the fifth resistor, a collector electrode of the second triode is connected with the grid electrode of the MOS tube, and an emitting electrode of the second triode is grounded.

Compared with the prior art, the beneficial effect of this application is:

the application discloses high temperature high voltage protection circuit includes: the circuit comprises a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a first triode, a second triode and an MOS (metal oxide semiconductor) tube. Wherein: the source electrode of the MOS tube is connected with the input end, and the drain electrode of the MOS tube is connected with the load. The first resistor, the third resistor and the sixth resistor are all connected with the input end. The first resistor and the second resistor are connected in series and then grounded, the base of the first triode is arranged between the first resistor and the second resistor, the collector is arranged between the third resistor and the fourth resistor, and the emitter is connected in a grounded mode. The first resistor, the second resistor and the third resistor control the switch of the first triode. The third resistor, the fourth resistor and the fifth resistor are sequentially connected in series and then grounded, the base of the second triode is arranged between the fourth resistor and the fifth resistor, the collector is connected with the grid of the MOS tube, and the emitter is grounded. The base voltage of the second triode is adjusted by a regulation and control circuit consisting of the first resistor, the second resistor, the third resistor and the first triode, and the switch of the MOS tube is adjusted by the state of the second triode. Under the normal state, the first triode works in the amplification region, the second triode works in the saturation region, at the moment, the grid electrode of the MOS tube is at a low level, and the source electrode and the drain electrode of the MOS tube are conducted. According to the characteristics of the triodes, when the temperature rises or the voltage of the input end rises, the base voltage of the second triode is reduced, the second triode is in a cut-off state, the grid electrode of the MOS tube is in a high level, the MOS tube is disconnected, and high-temperature and high-voltage protection on the load is realized.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.

Drawings

In order to more clearly explain the technical solution of the present application, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious to those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic diagram of a connection relationship of an optical communication terminal;

FIG. 2 is a schematic diagram of an optical network unit;

fig. 3 is a schematic structural diagram of an optical module according to an embodiment of the present disclosure;

FIG. 4 is a schematic diagram of an exploded structure of an optical module according to an embodiment of the present application;

fig. 5 is a schematic diagram of a high-temperature and high-voltage protection circuit according to an embodiment of the present disclosure;

fig. 6 is a schematic current flow diagram of the high-temperature high-voltage protection circuit provided in fig. 5.

Detailed Description

In order to make those skilled in the art better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

One of the core links of optical fiber communication is the interconversion of optical and electrical signals. The optical fiber communication uses optical signals carrying information to transmit in information transmission equipment such as optical fibers/optical waveguides, and the information transmission with low cost and low loss can be realized by using the passive transmission characteristic of light in the optical fibers/optical waveguides; meanwhile, the information processing device such as a computer uses an electric signal, and in order to establish information connection between the information transmission device such as an optical fiber or an optical waveguide and the information processing device such as a computer, it is necessary to perform interconversion between the electric signal and the optical signal.

The optical module realizes the function of interconversion of optical signals and electrical signals in the technical field of optical fiber communication, and the interconversion of the optical signals and the electrical signals is the core function of the optical module. The optical module is electrically connected with an external upper computer through a golden finger on an internal circuit board of the optical module, and the main electrical connection comprises power supply, I2C signals, data signals, grounding and the like; the electrical connection mode realized by the gold finger has become the mainstream connection mode of the optical module industry, and on the basis of the mainstream connection mode, the definition of the pin on the gold finger forms various industry protocols/specifications.

Fig. 1 is a schematic diagram of connection relationship of an optical communication terminal. As shown in fig. 1, the connection of the optical communication terminal mainly includes the interconnection among the optical network terminal 100, the optical module 200, the optical fiber 101 and the network cable 103;

one end of the optical fiber 101 is connected with a far-end server, one end of the network cable 103 is connected with local information processing equipment, and the connection between the local information processing equipment and the far-end server is completed by the connection between the optical fiber 101 and the network cable 103; and the connection between the optical fiber 101 and the network cable 103 is made by the optical network terminal 100 having the optical module 200.

An optical port of the optical module 200 is externally accessed to the optical fiber 101, and establishes bidirectional optical signal connection with the optical fiber 101; an electrical port of the optical module 200 is externally connected to the optical network terminal 100, and establishes bidirectional electrical signal connection with the optical network terminal 100; the optical module realizes the interconversion of optical signals and electric signals, thereby realizing the establishment of information connection between the optical fiber and the optical network terminal; specifically, the optical signal from the optical fiber is converted into an electrical signal by the optical module and then input to the optical network terminal 100, and the electrical signal from the optical network terminal 100 is converted into an optical signal by the optical module and input to the optical fiber.

The optical network terminal is provided with an optical module interface 102, which is used for accessing an optical module 200 and establishing bidirectional electric signal connection with the optical module 200; the optical network terminal is provided with a network cable interface 104, which is used for accessing the network cable 103 and establishing bidirectional electric signal connection with the network cable 103; the optical module 200 is connected to the network cable 103 through the optical network terminal 100, specifically, the optical network terminal transmits a signal from the optical module to the network cable and transmits the signal from the network cable to the optical module, and the optical network terminal serves as an upper computer of the optical module to monitor the operation of the optical module.

At this point, a bidirectional signal transmission channel is established between the remote server and the local information processing device through the optical fiber, the optical module, the optical network terminal and the network cable.

Common information processing apparatuses include routers, switches, electronic computers, and the like; the optical network terminal is an upper computer of the optical module, provides data signals for the optical module, and receives the data signals from the optical module, and the common upper computer of the optical module also comprises an optical line terminal and the like.

Fig. 2 is a schematic diagram of an optical network terminal structure. As shown in fig. 2, the optical network terminal 100 has a circuit board 105, and a cage 106 is disposed on a surface of the circuit board 105; an electric connector is arranged in the cage 106 and used for connecting an electric port of an optical module such as a golden finger; the cage 106 is provided with a heat sink 107, and the heat sink 107 has a projection such as a fin that increases a heat radiation area.

The optical module 200 is inserted into the optical network terminal, specifically, the electrical port of the optical module is inserted into the electrical connector inside the cage 106, and the optical port of the optical module is connected to the optical fiber 101.

The cage 106 is positioned on the circuit board, and the electrical connector on the circuit board is wrapped in the cage, so that the electrical connector is arranged in the cage; the optical module is inserted into the cage, held by the cage, and the heat generated by the optical module is conducted to the cage 106 and then diffused by the heat sink 107 on the cage.

Fig. 3 is a schematic view of an optical module according to an embodiment of the present disclosure, and fig. 4 is a schematic view of an exploded structure of an optical module according to an embodiment of the present disclosure. As shown in fig. 3 and 4, an optical module 200 provided in the embodiment of the present application includes an upper housing 201, a lower housing 202, an unlocking member 203, a circuit board 300, a light emitting device 301, and a light receiving device 400;

the upper shell 201 is covered on the lower shell 202 to form a wrapping cavity with two openings; the outer contour of the wrapping cavity is generally a square body, and specifically, the lower shell comprises a main plate and two side plates which are positioned at two sides of the main plate and are perpendicular to the main plate; the upper shell comprises a cover plate, and the cover plate covers two side plates of the upper shell to form a wrapping cavity; the upper shell can also comprise two side walls which are positioned at two sides of the cover plate and are perpendicular to the cover plate, and the two side walls are combined with the two side plates to realize that the upper shell covers the lower shell.

The two openings may be two ends (204, 205) in the same direction, or two openings in different directions; one opening is an electric port 204, and a gold finger of the circuit board extends out of the electric port 204 and is inserted into an upper computer such as an optical network terminal; the other opening is an optical port 205 for external optical fiber access to connect with the optical transceiver 400 inside the optical module; the photoelectric devices such as the circuit board 300 and the optical transceiver 400 are positioned in the packaging cavity.

The assembly mode of combining the upper shell and the lower shell is adopted, so that the circuit board 300, the optical transceiver 400 and other devices can be conveniently installed in the shells, and the upper shell and the lower shell form the outermost packaging protection shell of the optical module; the upper shell and the lower shell are made of metal materials generally, so that electromagnetic shielding and heat dissipation are facilitated; generally, the housing of the optical module is not made into an integrated component, so that when devices such as a circuit board and the like are assembled, the positioning component, the heat dissipation component and the electromagnetic shielding component cannot be installed, and the production automation is not facilitated.

The unlocking component 203 is located on the outer wall of the wrapping cavity/lower shell 202, and is used for realizing the fixed connection between the optical module and the upper computer or releasing the fixed connection between the optical module and the upper computer.

The unlocking component 203 is provided with a clamping component matched with the upper computer cage; the end of the unlocking component can be pulled to enable the unlocking component to move relatively on the surface of the outer wall; the optical module is inserted into a cage of the upper computer, and the optical module is fixed in the cage of the upper computer by a clamping component of the unlocking component; by pulling the unlocking component, the clamping component of the unlocking component moves along with the unlocking component, so that the connection relation between the clamping component and the upper computer is changed, the clamping relation between the optical module and the upper computer is released, and the optical module can be drawn out from the cage of the upper computer.

The circuit board 300 is provided with circuit traces, electronic components (such as capacitors, resistors, triodes, and MOS transistors), and chips (such as an MCU, a laser driver chip, a limiting amplifier chip, a clock data recovery CDR, a power management chip, and a data processing chip DSP).

The circuit board connects the electrical appliances in the optical module together according to the circuit design through circuit wiring to realize the functions of power supply, electrical signal transmission, grounding and the like.

The circuit board is generally a hard circuit board, and the hard circuit board can also realize a bearing effect due to the relatively hard material of the hard circuit board, for example, the hard circuit board can stably bear a chip; when the optical transceiver is positioned on the circuit board, the rigid circuit board can also provide stable bearing; the hard circuit board can also be inserted into an electric connector in the upper computer cage, and specifically, a metal pin/golden finger is formed on the surface of the tail end of one side of the hard circuit board and is used for being connected with the electric connector; these are not easily implemented with flexible circuit boards.

A flexible circuit board is also used in a part of the optical module to supplement a rigid circuit board; the flexible circuit board is generally used in combination with a rigid circuit board, for example, the rigid circuit board may be connected to the optical transceiver device through the flexible circuit board.

The circuit board is provided with a power management chip, one end of the power management chip is connected with a power supply, and the other end of the power management chip is connected with a load, so that power supply to the load is realized.

Fig. 5 is a schematic diagram of a high-temperature and high-voltage protection circuit provided in an embodiment of the present application, in order to avoid overload of a load caused by too high voltage or too high temperature inside an optical module, the embodiment of the present application provides a high-temperature and high-voltage protection circuit, which is disposed between a power management chip and the load. With reference to fig. 5, an embodiment of the present application provides a high-temperature and high-voltage protection circuit, including: VIN represents the power input end, VOUT represents the power output end, and the output end is connected with a load. A first terminal of the first resistor R1 is connected to the input terminal. And a second resistor R2 having a first end connected to the second end of the first resistor and a second end connected to ground. A first end of the third resistor R3 is connected to the input terminal. A fourth resistor R4, a first end of which is connected with a second end of the third resistor R3; a first end of the fifth resistor R5 is connected to the second end of the fourth resistor R4, and a second end is grounded. The base of the first triode Q1 is arranged between the first resistor R1 and the second resistor R2, the collector of the first triode Q1 is arranged between the third resistor R3 and the fourth resistor R4, and the emitter of the first triode Q1 is grounded. And a second triode Q2, wherein the base electrode of the second triode Q2 is arranged between the fourth resistor and the fifth resistor, the collector electrode of the second triode Q2 is connected with the grid electrode of the MOS tube Q3, and the emitter electrode of the second triode Q2 is grounded. The source of the MOS transistor Q3 is connected to the input terminal, and the drain is connected to the load. One end of the sixth resistor R6 is connected to the source of the MOS transistor Q3, and the other end of the sixth resistor R6 is connected to the gate of the MOS transistor Q3. In this embodiment, the power input terminal is a power management chip, and the load is an MCU, a laser driver chip, or an amplitude limiting amplifier chip on the circuit board.

The input end is connected with the first resistor R1 and the second resistor R2 in series and then grounded, the base of the first triode Q1 is arranged between the first resistor R1 and the second resistor R2, the collector is arranged between the third resistor R3 and the fourth resistor R4, and the emitter is grounded. The first resistor R1, the second resistor R2 and the third resistor R3 control the switching of the first transistor Q1. The input end is connected with the third resistor R3, the fourth resistor R4 and the fifth resistor R5 in series in sequence and then grounded, the base of the second triode Q2 is arranged between the fourth resistor R4 and the fifth resistor R5, the collector is connected with the grid of the MOS transistor Q3, and the emitter is connected with the ground. The regulation and control circuit composed of the first resistor R1, the second resistor R2, the third resistor R3 and the first triode Q1 can regulate the base voltage of the second triode Q2, and the state of the second triode Q2 can regulate the switch of the MOS tube Q3.

Further, the first transistor Q1 and the second transistor Q2 are NPN transistors. The MOS tube Q3 is a P-channel MOS tube.

Fig. 6 is a schematic diagram of a current flow direction of the high-temperature and high-voltage protection circuit shown in fig. 5, wherein (i) in fig. 6 and 5 represents the position 1, the position 2, and the position 3.

Under normal conditions, the site 1 voltage is above the turn-on voltage of the first transistor Q1 and the site 2 voltage is above the turn-on voltage of the second transistor Q2. The first transistor Q1 operates in the amplification region, the second transistor Q2 operates in the saturation region, the gate of the MOS transistor Q3 is at a low level, and the source and the drain of the MOS transistor Q3 are turned on. In order to ensure that the first transistor Q1 operates in the amplification region under normal conditions (no high temperature and high voltage), the resistance of the first resistor R1 is greater than the resistance of the third resistor R3.

According to the characteristics of the triodes, when the temperature rises, the amplification factor of the first triode Q1 increases (beta increases by about 0.5-1% every time the temperature rises by 1 ℃), the current value of the third resistor R3 increases, the divided voltage of the third resistor R3 increases, the divided voltage of the fourth resistor R4 and the fifth resistor R5 decreases, the base voltage of the second triode Q3 decreases until the base voltage is smaller than the on-state voltage of the second triode Q2, at this time, the second triode Q2 is cut off, the gate of the MOS transistor is at a high level, the MOS transistor Q3 is cut off, and at this time, VOUT is 0.

When the voltage at the input terminal rises, due to the voltage dividing action of the first resistor R1 and the second resistor R2, VIN increases so that the voltage applied to the first triode Q3 increases, the base current also increases, the output current increases with the increase of the input current according to the amplifying action of the triodes, Ic becomes higher, and Vce gradually decreases (compared with the temperature rise, the reason is different, but the result is the same), that is, the voltage at the position 2 gradually decreases until the voltage is smaller than the on-state voltage of Q2, Q2 is turned off, the position 3 is at a high level, Q3 is turned off, and VOUT is equal to 0 at this time. And the MOS tube is disconnected, so that high-temperature and high-voltage protection on the load is realized.

In some embodiments, in order to make the high-temperature and high-voltage protection circuit more adaptable, the first resistor R1, the second resistor R2, the third resistor R3, the fourth resistor R4, the fifth resistor R5 and the sixth resistor R6 are adjustable resistors. The resistances of the first resistor R1, the second resistor R2, the third resistor R3, the fourth resistor R4, the fifth resistor R5 and the sixth resistor R6 can be adjusted according to the requirements of the use environment such as protection voltage value and temperature value.

In some examples, the high temperature and high voltage protection circuit further comprises: one end of the first capacitor C1 is connected to the base of the first transistor Q1, and the other end is connected to the emitter of the first transistor Q1. The first capacitor C1 is used for high-frequency filtering, and the anti-interference capability of the first triode Q1 is improved. When high-frequency alternating current noise interference comes, the first capacitor C1 can short circuit the interference to the ground, so that the interference is eliminated.

In a similar way, the high-temperature and high-voltage protection circuit further comprises: and one end of the second capacitor C2 is connected with the base of the second triode Q2, and the other end is connected with the emitter of the second triode Q2. The second capacitor C2 is used for high-frequency filtering, and the anti-interference capability of the first triode Q2 is improved. When high-frequency alternating-current noise interference comes, the second capacitor C2 can short circuit the interference to the ground, so that the interference is eliminated.

Since the function of the whole circuit is based on the temperature characteristic of the triode, the resistances of the resistors R1, R2 and R3 of the circuit are basically dependent on the parameters of the triode.

The first transistor Q1 and the second transistor Q2 may be the same or different in type and specification. In some embodiments, to facilitate the adjustment of the first resistor R1, the second resistor R2, the third resistor R3, the fourth resistor R4, the fifth resistor R5, and the sixth resistor R6, the first transistor Q1 is the same as the second transistor Q2, and has a turn-on voltage of 0.3V. When the design is performed, the base voltages of the first transistor Q1 and the second transistor Q2 are greater than 0.3, and about 0.5V, then R1: R2 is 23:1, and 23K and 1K can be selected. Ensuring that Q1 operates in the amplification region. V2 ═ VIN-R3Ic1(Ib2 is small and neglected), and the resistance of the third resistor R3 can be calculated from the amplification factor of the transistor. Because the first triode and the second triode are the same in model, R4 and R5 do not need to divide voltage, the resistance value R4 of the fourth resistor can be set to 0 ohm, and the value of R5 has no special requirement and can be set to 10K.

If the first transistor Q1 and the second transistor Q2 have different specifications, the fourth resistor R4 and the fifth resistor R5 can be used to set the state of the second transistor Q2 during normal operation.

In some embodiments, the emitter-to-ground resistance of the transistor may be further configured to stabilize the operating point and improve the switching characteristics of the transistor. Because the transistor has a storage time from turning on to turning off, and the storage time is increased along with the rise of the temperature, the emitter resistance can inhibit the rate of the change, thereby accelerating the turning off of the transistor and avoiding the deep saturation of the triode.

In practical application, debugging is often required according to the actual condition of the single board, and the debugging direction can be guided according to theory. The following are specific examples of the present application:

1) r1 ═ 24.3K, R2 ═ 1.1K, R3 ═ 10K, R4 ═ 0, R5 ═ 10K, R6 ═ 10K, C1 ═ C2 ═ 100nF, Q1 ═ Q2 ═ MMBT 3904. The protective voltage is about 18-19V, and the temperature is about 70 ℃.

2) R1 ═ 24.3K, R2 ═ 1.1K, R3 ═ 1.1K, R4 ═ 0, R5 ═ 10K, R6 ═ 10K, C1 ═ C2 ═ 100nF, Q1 ═ Q2 ═ MMBT 3904. The protective voltage is about 18-19V, and the temperature is about 100 ℃.

3) R1 ═ 18K, R2 ═ 1.1K, R3 ═ 10K, R4 ═ 0, R5 ═ 10K, R6 ═ 10K, C1 ═ C2 ═ 100nF, Q1 ═ Q2 ═ MMBT 3904. The protective voltage is about 14V, and the temperature is about 60 ℃.

To sum up, the application discloses high temperature high pressure protection circuit includes: the circuit comprises a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a first triode, a second triode and an MOS (metal oxide semiconductor) tube. Wherein: the source electrode of the MOS tube is connected with the input end, and the drain electrode of the MOS tube is connected with the load. The first resistor, the third resistor and the sixth resistor are all connected with the input end. The first resistor and the second resistor are connected in series and then grounded, the base of the first triode is arranged between the first resistor and the second resistor, the collector is arranged between the third resistor and the fourth resistor, and the emitter is connected in a grounded mode. The first resistor, the second resistor and the third resistor control the switch of the first triode. The third resistor, the fourth resistor and the fifth resistor are sequentially connected in series and then grounded, the base of the second triode is arranged between the fourth resistor and the fifth resistor, the collector is connected with the grid of the MOS tube, and the emitter is grounded. The base voltage of the second triode is adjusted by a regulation and control circuit consisting of the first resistor, the second resistor, the third resistor and the first triode, and the switch of the MOS tube is adjusted by the state of the second triode. Under the normal state, the first triode works in the amplification region, the second triode works in the saturation region, at the moment, the grid electrode of the MOS tube is at a low level, and the source electrode and the drain electrode of the MOS tube are conducted. According to the characteristics of the triodes, when the temperature rises or the voltage of the input end rises, the base voltage of the second triode is reduced, the second triode is in a cut-off state, the grid electrode of the MOS tube is in a high level, the MOS tube is disconnected, and high-temperature and high-voltage protection on the load is realized. The high-temperature high-voltage circuit is arranged at the position of external power supply input, all circuits at the rear end can be protected when the high-temperature high-voltage circuit enters a protection state, the design is simple, and the cost is low.

Since the above embodiments are all described by referring to and combining with other embodiments, the same portions are provided between different embodiments, and the same and similar portions between the various embodiments in this specification may be referred to each other. And will not be described in detail herein.

It is noted that, in this specification, relational terms such as "first" and "second," and the like, are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a circuit structure, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such circuit structure, article, or apparatus. Without further limitation, the presence of an element identified by the phrase "comprising an … …" does not exclude the presence of other like elements in a circuit structure, article or device comprising the element.

Other embodiments of the present application will be apparent to those skilled in the art from consideration of the specification and practice of the present disclosure. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the application being indicated by the following claims.

The above-described embodiments of the present application do not limit the scope of the present application.

Claims (10)

1. A high temperature and high voltage protection circuit, comprising:

the source electrode of the MOS tube is connected with the input end, and the drain electrode of the MOS tube is connected with the load;

a first resistor, the first end of which is connected with the input end;

a first end of the second resistor is connected with a second end of the first resistor, and the second end of the second resistor is grounded;

a first end of the third resistor is connected with the input end;

a first end of the fourth resistor is connected with a second end of the third resistor;

a first end of the fifth resistor is connected with a second end of the fourth resistor, and the second end of the fifth resistor is grounded;

a base electrode of the first triode is arranged between the first resistor and the second resistor, a collector electrode of the first triode is arranged between the third resistor and the fourth resistor, and an emitting electrode of the first triode is grounded;

a base electrode of the second triode is arranged between the fourth resistor and the fifth resistor, a collector electrode of the second triode is connected with a grid electrode of the MOS tube, and an emitting electrode of the second triode is grounded;

and one end of the sixth resistor is connected with the source electrode of the MOS tube, and the other end of the sixth resistor is connected with the grid electrode of the MOS tube.

2. A high-temperature high-voltage protection circuit according to claim 1, further comprising: and one end of the first capacitor is connected with the base electrode of the first triode, and the other end of the first capacitor is connected with the emitting electrode of the first triode.

3. A high-temperature high-voltage protection circuit according to claim 1, further comprising: and one end of the second capacitor is connected with the base electrode of the second triode, and the other end of the second capacitor is connected with the emitting electrode of the second triode.

4. A high-temperature high-voltage protection circuit according to claim 1, wherein the resistance of the first resistor is greater than the resistance of the third resistor.

5. The high-temperature high-voltage protection circuit according to claim 1, wherein the first transistor and the second transistor are NPN transistors.

6. The high-temperature high-voltage protection circuit according to claim 1, wherein the MOS transistor is a P-channel MOS transistor.

7. The protection circuit of claim 1, wherein the first resistor, the second resistor, the third resistor, the fourth resistor, the fifth resistor, and the sixth resistor are adjustable resistors.

8. The protection circuit of claim 7, wherein the first transistor is of the same type as the second transistor.

9. A high-temperature high-voltage protection circuit according to claim 8, wherein the fourth resistor has a resistance of 0 ohm.

10. A light module, comprising: a circuit board having the high temperature and high voltage protection circuit of any one of claims 1 to 9 disposed thereon.

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