CN210350783U - Overcurrent protection circuit, analog quantity data acquisition board card and nuclear power station instrument control device - Google Patents
Overcurrent protection circuit, analog quantity data acquisition board card and nuclear power station instrument control device Download PDFInfo
- Publication number
- CN210350783U CN210350783U CN201920969201.0U CN201920969201U CN210350783U CN 210350783 U CN210350783 U CN 210350783U CN 201920969201 U CN201920969201 U CN 201920969201U CN 210350783 U CN210350783 U CN 210350783U
- Authority
- CN
- China
- Prior art keywords
- current
- impedance element
- impedance
- input current
- circuit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Emergency Protection Circuit Devices (AREA)
Abstract
The utility model belongs to the technical field of nuclear power station control system, lack the technical problem that can effectively protect to the electric current with simple and easy circuit in order to solve prior art, the utility model provides an overcurrent protection circuit, analog quantity data acquisition integrated circuit board, nuclear power station instrument control device, overcurrent protection circuit includes: a power tube for receiving input current, a switching element; and a first impedance element and a second impedance element connected in parallel with the power tube and the switching element, respectively; when the input current is in the range from Ia to Ib, the first impedance element provides a bias voltage for conducting the power tube, and when the input current is greater than Ib, the large impedance of the first impedance element prevents the loop current from increasing; the second impedance element is configured to: when the input current is less than Ia, the divided voltage of the second impedance element is small, the switching element is in an off state, and when the input current is in Ib, the second impedance element reaches a saturated on state of the switching element, so that a constant current is formed. Therefore, overcurrent protection can be performed, and the cost can be reduced.
Description
Technical Field
The utility model relates to a nuclear power station control system's technical field especially relates to an overcurrent protection circuit, analog quantity data acquisition integrated circuit board, nuclear power station instrument control device.
Background
The current protection elements are arranged in the common power supply circuit or the common signal transmission circuit in the working process, so that the working safety of the circuit is ensured, and the current protection elements are required to be arranged in various circuits of a nuclear power station control system with high safety requirement.
The current protection is mainly realized by heating and fusing a device, for example, a fuse and a PTC thermistor are common overcurrent protection devices; however, the minimum starting current of the device is high from the application point of view, and the minimum starting current of the device also needs to reach about 100 mA.
The inventor discovers that: the magnitude range of the current signal input in the nuclear power station control system is usually in the middle, so the realization scheme of fusing through device heating in the prior art does not achieve the purpose of protecting 4-20 mA current. Another conceivable solution is to build the acquisition circuit by means of a comparator, but this implementation is complicated.
Therefore, it is desirable to provide a circuit capable of protecting 4 to 20mA of input current without burden.
It should be noted that the above technical solutions are only for making the technical solution of the present invention easier for those skilled in the art to understand, and are not the above technical solutions all belonging to the prior art.
SUMMERY OF THE UTILITY MODEL
In order to solve the technical problem that can effectively protect the electric current with simple and easy circuit among the prior art, the utility model provides an overcurrent protection circuit, analog quantity data acquisition integrated circuit board, nuclear power station appearance accuse device can carry out overcurrent protection, and realize with low costs.
In order to achieve the above object, the present invention provides a technical solution comprising:
an aspect of the utility model provides an overcurrent protection circuit, overcurrent protection circuit is used for protecting the electric current between Ia ~ Ib, overcurrent protection circuit establishes ties between input current and sampling resistor, a serial communication port, include:
the power tube receives the input current, and the switching element is connected with the power tube; and
a first impedance element and a second impedance element connected in parallel to the power transistor and the switching element, respectively; the first impedance element is configured to: when the input current is in a range from Ia to Ib, the first impedance element provides a bias voltage for conducting the power tube, and when the input current is larger than Ib, the large impedance of the first impedance element prevents the loop current from increasing; the second impedance element is configured to: when the input current is smaller than Ia, the divided voltage of the second impedance element is small, the switch element is in an off state, and when the input current is in Ib, the second impedance element reaches a saturated on state of the switch element, so that a constant current is formed.
In a preferred embodiment of the present invention, the power transistor is a first transistor, and the switching element is a second transistor; a collector of the first triode is connected with an input current signal, and an emitter of the first triode is connected with a base of the second triode; two ends of the first impedance element are respectively connected with a collector and a base of the first triode in parallel; and two ends of the second impedance element are respectively connected with the base electrode and the emitting electrode of the second triode in parallel.
In a preferred embodiment of the present invention, Ia is 4mA, Ib is 20 mA; the impedance range of the first impedance element is 1k omega-100 k omega, and the impedance range of the second impedance element is not more than 23 omega.
In a further preferred embodiment of the present invention, when the input current is smaller than Ia, since the switching tube is not turned on, the current IR1 passing through the first impedance element is small, the current in the overcurrent protection circuit passes through the second impedance element, the current of the second impedance element is IR2, and when the current of the second impedance element reaches a predetermined value, the switching element is turned on in saturation, so that the current IR2 passing through the second impedance element connected in parallel with the switching element approaches a constant current state and becomes small; after that, the increased current passes through the first impedance element loop, and when the current IR1 of the first impedance element becomes larger due to the impedance of the first impedance element, the voltage required across the first impedance element needs to be higher according to ohm's law, and the voltage required for increasing the current IR1 cannot be provided due to the limited driving voltage of the previous stage circuit, so that the larger current IR1 is limited from being input to the sampling resistor.
The utility model discloses the second aspect still provides an analog data acquisition integrated circuit board, a serial communication port, include:
the input current interface is used for receiving current between Ia and Ib;
a sampling resistor configured to output an analog voltage signal based on the sampling resistor; and
an overcurrent protection circuit disposed between the input current interface and the sampling resistor, wherein the overcurrent protection circuit is any one of the overcurrent protection circuits provided in the first aspect.
The utility model discloses in preferred embodiment, analog quantity data acquisition integrated circuit board is still including setting up input current interface with prevent the reverse-connection circuit between the sampling resistor other end, and prevent reverse-connection circuit including the diode, the positive pole orientation of diode sampling resistor, the negative pole orientation of diode input current interface.
The utility model discloses in the preferred embodiment, analog quantity data acquisition integrated circuit board still include in proper order with filter circuit, conditioning circuit, analog-to-digital conversion circuit, digital isolation circuit and the treater that sampling resistance connects.
The utility model discloses in the preferred embodiment, the sampling resistance is high-accuracy resistance, just high-accuracy resistance is in the foremost of sampling passageway.
In a preferred embodiment of the present invention, the sampling resistor has a range of 25 Ω to 200 Ω.
The utility model discloses the third aspect still provides a nuclear power station instrument control device, a serial communication port, include:
the analog quantity data acquisition board card provided by the second aspect, and the cabinet for installing the analog quantity data acquisition board card.
By adopting the technical scheme provided by the application, at least one of the following beneficial effects can be obtained:
1. the power tube (such as a triode) and the switching element (such as a triode) are combined, the power tube bears the energy during overcurrent, and the aim of limiting the loop current is achieved through the varistor characteristic; and when the signal is in the effective range, the equivalent impedance is small, the influence on the preceding stage driving is small, and the effective signal is not shunted, so that the precision loss is not caused.
2. The starting current can be set, and effective protection can be performed on a sampling resistor simulating 4-20 mA; the protection effect is good, and the protection blank of a common overcurrent device in the range is made up; therefore, an effective overcurrent protection solution can be provided for circuits in the instrument control system of the nuclear power station.
3. The circuit complexity is low, the circuit precision is not influenced, and the cost is low; and the components and parts realized by the circuit do not need special customization, and the engineering progress in the specific realization process can not be influenced.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure and/or process particularly pointed out in the written description and claims hereof as well as the appended drawings.
Drawings
Fig. 1 is a block diagram of an embodiment of the present invention, which illustrates an over-current protection circuit.
Fig. 2 is a circuit diagram of an overcurrent protection circuit according to another embodiment of the present invention.
Fig. 3 is a first simulation effect diagram of the current variation flowing through the transistor Q1 and the transistor Q2 in the overcurrent protection circuit of fig. 2.
Fig. 4 is a diagram of a simulation effect of a current change flowing through the transistor Q1 and the transistor Q2 in the overcurrent protection circuit of fig. 2.
Fig. 5 is a circuit diagram corresponding to the analog data acquisition board card provided by the embodiment of the present invention.
Detailed Description
The following detailed description will be made with reference to the accompanying drawings and examples, so as to solve the technical problems by applying technical means to the present invention, and to fully understand and implement the technical effects of the present invention. It should be noted that the specific description is only for the purpose of making the present invention easier and clearer for those skilled in the art to understand, and is not a limiting explanation of the present invention; and as long as no conflict is formed, the embodiments and the features in the embodiments of the present invention can be combined with each other, and the technical solutions formed are all within the scope of the present invention.
The technical solution of the present invention is described in detail below with reference to the accompanying drawings and specific embodiments:
examples
As shown in fig. 1, the present embodiment provides an overcurrent protection circuit, where the overcurrent protection circuit is used to protect currents Ia to Ib, the overcurrent protection circuit is disposed between an input current and a sampling resistor, and the overcurrent protection circuit includes:
a power transistor 110 (e.g., a high power transistor) receiving an input current, and a switching element 120 (e.g., a transistor) connected to the power transistor; and
a first impedance element 130 and a second impedance element 140 connected in parallel to the power transistor 110 and the switching element 120, respectively; in the implementation process of this embodiment, the power tube 110, the switching element 120, the first impedance element 130 and the second impedance element 140 that are required may use different devices of different manufacturers to achieve the same purpose, and therefore, the specific structure thereof is not limited.
Wherein the first impedance element 130 is arranged to: when the input current is at Ia～IbWhen the input current is greater than I, the first impedance element 130 provides a bias voltage for turning on the power transistor 110, and the power transistor 110 is turned onbAt this time, the large impedance of the first impedance element 130 hinders the increase of the loop current; the second impedance element 140 is arranged to: when the input current is less than IaWhen the input current is in Ib, the second impedance element 140 reaches the saturation conduction state of the switching element, and thus a constant current is formed.
Therefore, the corresponding overcurrent protection circuit between the input end and the output end can only allow the input current to be in Ia-IbAnd for a value less than IaIs insufficient to drive the conduction of the switching element 120 for currents greater than IbThe power tube 110 can be turned off by dividing the voltage through the first impedance element, so that the current cannot flow out to the output terminal. Therefore, the above technical solution provided by this embodiment can implement:
1. the power tube (such as a triode) and the switching element (such as a triode) are combined, the power tube bears the energy during overcurrent, and the aim of limiting the loop current is achieved through the varistor characteristic; and when the signal is in the effective range, the equivalent impedance is small, the influence on the preceding stage driving is small, and the effective signal is not shunted, so that the precision loss is not caused.
2. The circuit complexity is low, the circuit precision is not influenced, and the cost is low; and the components and parts realized by the circuit do not need special customization, and the engineering progress in the specific realization process can not be influenced.
3. The protection circuit is connected in series in the circuit, so that no branch exists, no current loss is caused, and no precision is lost.
As shown in fig. 2, in a preferred embodiment of this embodiment, the power transistor is a first transistor Q1, and the switching element is a second transistor Q2; the collector of the first triode Q1 is connected with the input current signal I1, and the emitter of the first triode Q1 is connected with the base of the second triode Q2; two ends of the first impedance element R1 are respectively connected with the collector and the base of the first triode Q1 in parallel; two ends of the second impedance element R2 are respectively connected with the base electrode and the emitting electrode of the second triode Q2 in parallel; of course, the first impedance element R1 and the second impedance element R2 in this embodiment are not limited to one resistance element, and a plurality of resistances may be connected in parallel or in series, or other impedance elements may be added.
In a further preferred embodiment of this embodiment, Ia is 4mA and Ib is 20 mA; the impedance range of the first impedance element is 1k omega-100 k omega (the resistance mainly prevents the current from increasing when the current is over-current, the larger the value is, the steeper the prevention curve is), and the impedance range of the second impedance element is not more than 23 omega (mainly considering the relation between the tube voltage drop 0.7V and 20mA, generally, in order to ensure fault tolerance, the protection current is generally set at 20mA which is 2 times).
In a further preferred embodiment of this embodiment, when the input current is less than Ia, since the switching tube is not yet turned on, the current IR1 passing through the first impedance element is small, the current in the overcurrent protection circuit passes through the second impedance element, and the current of the second impedance element is IR2, when the current of the second impedance element reaches a predetermined value, the switching element is in saturated conduction, so that the current IR2 passing through the second impedance element connected in parallel with the switching element approaches a constant current state and becomes small; when the current IR1 of the first impedance element becomes large due to the impedance of the first impedance element after the increased current passes through the first impedance element loop, the voltage required across the first impedance element becomes high according to the ohm's law, and the voltage required for increasing the current IR1 cannot be supplied because the driving voltage of the preceding stage circuit is limited, thereby limiting the input of the large current IR1 to the sampling resistor. Specifically, the method comprises the following steps: when the input current is small, the primary function of the first impedance element is to provide a turn-on voltage for Q1, and the path current is substantially entirely through the path of Q1 and the second impedance element. When the current on the second impedance element reaches a certain value, the voltage of the second impedance element is clamped by the be end PN junction of the Q2, and then the voltage does not increase continuously, so that the path enters a substantially constant current state; after that, the total current is increased only through the first impedance element and the Q2 path, but the first impedance element has high impedance, so that the current is slightly increased by high voltage and power support, and the power and voltage of the actual driving circuit are limited, so that the continuous increase of the current cannot be supported, thereby forming protection. Most of the power drops to Q1, so Q1 needs a large power tube, otherwise it is easy to burn out.
The starting current can be set to effectively protect a sampling resistor simulating 4-20 mA; the protection effect is good, and the protection blank of a common overcurrent device in the range is made up; therefore, an effective overcurrent protection solution can be provided for circuits in the instrument control system of the nuclear power station.
As shown in fig. 3 and 4, a schematic diagram of a change of a current flowing through a transistor Q1 and a transistor Q2 in the overcurrent protection circuit is obtained by inputting analog simulation; wherein:
ie (Q1), Ie (Q2) represent the currents IR1 and IR2 flowing through the two branches of the transistors Q1 and Q2, respectively, in the protection circuit, while I represents the current of the main loop (IR1+ IR 2); u is the voltage drop across the protection circuit, using the voltage coordinate on the left side.
As can be seen from the simulation results of fig. 3 and 4:
1) the driving capability of the main current source is enough, the total current of the loop shows linear change and is equal to the sum of the currents of the two loops of the protection circuit, and therefore the protection circuit does not lose precision.
2) The two loops of the protection circuit start to change when the current is higher than 40mA, and the voltage at two ends of the protection circuit starts to increase. Indicating that the voltage across the protection circuit must reach the voltage value required for simulation to maintain a stable current output.
Because the simulation adopts an ideal current source, the power of a driving device in real application is limited, and the current is limited by using the principle. In addition, in the circuit, the Q1 is a more important device, and all energy generated by overcurrent is concentrated on the device, so that the device needs to select a power tube; the main role of Q2 is switching; when the current is small, the IR1 is small, most of the current passes through the IR2, when the current on the R2 reaches a certain value, Q2 is conducted, after that, the change of the IR2 is small, the change of the IR1 is large, but because the resistance value of the R1 is large, the voltage and the power required by the current increase need to be increased sharply, and the general-purpose device basically does not have the driving capability, so that the current limiting purpose is achieved.
As shown in fig. 5, this embodiment further provides an analog data acquisition board card, where the analog data acquisition board card includes:
an input current interface for receiving Ia～IbThe current in between;
a sampling resistor 200 arranged to output an analog voltage signal based on the sampling resistor; and
and the overcurrent protection circuit 100 is arranged between the input current interface and the sampling resistor, and is any one of the overcurrent protection circuits provided as the above.
The specific implementation of the overcurrent protection circuit in the analog quantity data acquisition board card is the same as that in fig. 1-4 and the above text explanation, and the same technical effect can be achieved; and will not be described in detail herein.
As shown in fig. 5, in a preferred embodiment of this embodiment, the analog data acquisition board further includes an anti-reverse connection circuit 300 disposed between the input current interface and the other end of the sampling resistor, and the anti-reverse connection circuit includes a diode, an anode of the diode faces the sampling resistor 300, and a cathode of the diode faces the input current interface. The protection circuit can not only inhibit overcurrent, but also inhibit long-time misconnection of 60V DC voltage signals. The reverse voltage signal can be restrained by the reverse connection preventing circuit, and the forward misconnection can be shared by the overcurrent protection circuit, so that the sampling resistor can not be damaged.
As shown in fig. 5, in a preferred embodiment of this embodiment, the analog data acquisition board further includes a filter circuit 400, a conditioning circuit 500, an analog-to-digital conversion circuit 600, a digital isolation circuit 700, and a processor 800, which are sequentially connected to the sampling resistor. The specific structures of the filter circuit, the conditioning circuit, the analog-to-digital conversion circuit, the digital isolation circuit and the processor can adopt the same circuit structures in the existing analog data acquisition board card, such as the filter circuit, the conditioning circuit, the analog-to-digital conversion circuit, the digital isolation circuit and the processor mentioned in the current acquisition board card in the Speedy Hold 2000 platform.
In a preferred embodiment of this embodiment, the sampling resistor is a high-precision resistor, and the high-precision resistor is located at the foremost end of the sampling channel.
In the preferred embodiment of the present invention, the sampling resistor has a range of 25 Ω to 200 Ω. Since the channel interface can cause the resistance damage due to misconnection of signals, and thus the whole analog channel fails, protection is necessary, and since the power of the high-precision sampling resistor provided by the embodiment does not exceed 1W, a protection circuit must be added.
This embodiment still provides a nuclear power station instrument control device, and this nuclear power station instrument control device includes:
the analog quantity data acquisition board card comprises any one of the analog quantity data acquisition board card and a cabinet for mounting the analog quantity data acquisition board card.
Therefore, by adopting the technical scheme provided by the embodiment, at least one of the following beneficial effects can be obtained:
1. the power tube (such as a triode) and the switching element (such as a triode) are combined, the power tube bears the energy during overcurrent, and the aim of limiting the loop current is achieved through the varistor characteristic; and when the signal is in the effective range, the equivalent impedance is small, the influence on the preceding stage driving is small, and the effective signal is not shunted, so that the precision loss is not caused.
2. The starting current can be set, and effective protection can be performed on a sampling resistor simulating 4-20 mA; the protection effect is good, and the protection blank of a common overcurrent device in the range is made up; therefore, an effective overcurrent protection solution can be provided for circuits in the instrument control system of the nuclear power station.
3. The circuit complexity is low, the circuit precision is not influenced, and the cost is low; and the components and parts realized by the circuit do not need special customization, and the engineering progress in the specific realization process can not be influenced.
Finally, it should be understood that the above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention in any way. The above disclosed embodiments and technical content can be utilized by any person skilled in the art to make many possible variations, simple substitutions and the like without departing from the scope of the present invention, which is within the protection scope of the present invention.
Claims (10)
1. An overcurrent protection circuit for protecting Ia～IbThe overcurrent protection circuit is connected in series between the input current and the sampling resistor, and the overcurrent protection circuit is characterized by comprising:
the power tube receives the input current, and the switching element is connected with the power tube; and
a first impedance element and a second impedance element connected in parallel to the power transistor and the switching element, respectively; the first impedance element is configured to: when the input current is at Ia～IbWhen the input current is larger than I, the first impedance element provides a bias voltage for conducting the power tube, and when the input current is larger than IbWhen the current is low, the large impedance of the first impedance element hinders the increase of the loop current; the second impedance element is configured to: when the input current is less than IaOf said second impedance elementThe voltage division is small, the switch element is in an off state, and when the input current is in IbWhen the second impedance element reaches the saturation conduction state of the switching element, a constant current is formed.
2. The overcurrent protection circuit of claim 1, wherein the power transistor is a first transistor, and the switching element is a second transistor; a collector of the first triode is connected with an input current signal, and an emitter of the first triode is connected with a base of the second triode; two ends of the first impedance element are respectively connected with a collector and a base of the first triode in parallel; and two ends of the second impedance element are respectively connected with the base electrode and the emitting electrode of the second triode in parallel.
3. The overcurrent protection circuit of claim 1 or claim 2, wherein I isaIs 4mA, said IbIs 20 mA; the impedance range of the first impedance element is 1k omega-100 k omega, and the impedance range of the second impedance element is not more than 23 omega.
4. The over-current protection circuit of claim 3, wherein when the input current is less than IaWhen the switch tube is not conducted, the current I passing through the first impedance elementR1When the current on the second impedance element reaches a preset value, the switching element is in saturated conduction, so that the current I flowing through the second impedance element connected with the switching element in parallel is enabled to flowR2Approaching a constant current state and thus becoming smaller; thereafter an increased current is looped through the first impedance element, the current I of the first impedance element being due to the impedance of the first impedance elementR1When the voltage across the first impedance element is increased, the voltage required across the first impedance element is increased according to ohm's law, and the current I cannot be supplied because the driving voltage of the preceding stage circuit is limitedR1Increasing the voltage required, thereby limiting the largerCurrent IR1Input to a sampling resistor.
5. The utility model provides an analog quantity data acquisition integrated circuit board which characterized in that includes:
an input current interface for receiving Ia～IbThe current in between;
a sampling resistor configured to output an analog voltage signal based on the sampling resistor; and
an overcurrent protection circuit arranged between the input current interface and the sampling resistor, wherein the overcurrent protection circuit is the overcurrent protection circuit as set forth in any one of claims 1 to 4.
6. The analog data acquisition board card according to claim 5, further comprising an anti-reverse connection circuit disposed between the input current interface and the other end of the sampling resistor, wherein the anti-reverse connection circuit comprises a diode, an anode of the diode faces the sampling resistor, and a cathode of the diode faces the input current interface.
7. The analog data acquisition board card of claim 5, further comprising a filter circuit, a conditioning circuit, an analog-to-digital conversion circuit, a digital isolation circuit, and a processor connected to the sampling resistor in sequence.
8. The analog data acquisition board card of claim 5, wherein the sampling resistor is a high precision resistor, and the high precision resistor is at the foremost end of the sampling channel.
9. The analog data acquisition board card of claim 5, wherein the sampling resistor is in a range of 25 Ω -200 Ω.
10. A nuclear power plant instrument control device, comprising:
an analog data acquisition board as claimed in any one of claims 5 to 9, and a cabinet for mounting the analog data acquisition board.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920969201.0U CN210350783U (en) | 2019-06-26 | 2019-06-26 | Overcurrent protection circuit, analog quantity data acquisition board card and nuclear power station instrument control device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920969201.0U CN210350783U (en) | 2019-06-26 | 2019-06-26 | Overcurrent protection circuit, analog quantity data acquisition board card and nuclear power station instrument control device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN210350783U true CN210350783U (en) | 2020-04-17 |
Family
ID=70190831
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201920969201.0U Active CN210350783U (en) | 2019-06-26 | 2019-06-26 | Overcurrent protection circuit, analog quantity data acquisition board card and nuclear power station instrument control device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN210350783U (en) |
-
2019
- 2019-06-26 CN CN201920969201.0U patent/CN210350783U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN104868884A (en) | General switching value input signal acquisition circuit | |
| CN103955250A (en) | Bandgap reference circuit with high power supply rejection ratio | |
| CN210350783U (en) | Overcurrent protection circuit, analog quantity data acquisition board card and nuclear power station instrument control device | |
| CN106033883A (en) | Discharging circuit | |
| CN104822198A (en) | Control circuit and control method for multiple paths of LED lamp strings | |
| CN207992860U (en) | Digital output circuit and industrial control equipment | |
| CN206481043U (en) | One kind carries multiple-channel output single channel short circuit over-current protection circuit | |
| CN104535887A (en) | Switch output circuit breaking diagnostic system and switch output module | |
| CN204669330U (en) | The Acquisition Circuit of universal On-off signal signal | |
| CN108768355A (en) | Fast conducting Pmos tube drive circuits and implementation method | |
| CN105425091A (en) | Large-power circuit connection resistance fault dynamic simulation system and method, and application | |
| CN205141638U (en) | Switching power supply output short circuit disconnection protection circuit | |
| CN107769759A (en) | One-way conduction device | |
| CN110323728A (en) | Current foldback circuit, analog data acquisition module card, nuclear power plant instrument control device | |
| CN103200726B (en) | The power supply circuits of the control circuit of LED illumination device and LED illumination device | |
| CN105811357B (en) | Current foldback circuit and the AI modules that the current foldback circuit is set | |
| CN102856880A (en) | Power supply overvoltage protecting circuit | |
| CN202977969U (en) | Efficient protection circuit of laser coupling power source | |
| CN204836660U (en) | Multichannel differential pressure sampling circuit | |
| CN103096569B (en) | Current-sharing circuit applicable to multi-channel loading | |
| CN209517094U (en) | A kind of dual-channel analog selection circuit | |
| CN206923057U (en) | A kind of detection control apparatus of heat shrinkable tube heater | |
| CN219086999U (en) | Redundant circuit of vehicle power supply | |
| CN206060723U (en) | Communicating circuit between AGV circuit boards | |
| CN116826657A (en) | Current-limiting protection circuit and equipment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |