CN204928079U - Current foldback circuit , power factor correction circuit and transducer air conditioning - Google Patents
Current foldback circuit , power factor correction circuit and transducer air conditioning Download PDFInfo
- Publication number
- CN204928079U CN204928079U CN201520657529.0U CN201520657529U CN204928079U CN 204928079 U CN204928079 U CN 204928079U CN 201520657529 U CN201520657529 U CN 201520657529U CN 204928079 U CN204928079 U CN 204928079U
- Authority
- CN
- China
- Prior art keywords
- circuit
- analog
- insulates
- digital conversion
- enlarging device
- 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
Abstract
The utility model discloses a current foldback circuit, power factor correction circuit and transducer air conditioning, wherein, current foldback circuit is including being arranged in concatenating sampling resistor, light buffer, analog to digital conversion circuit and the controller at the current loop by detection circuitry, light buffer just, the negative input end connects the both ends of sampling resistor respectively to receive the input of the voltage on the sampling resistor, analog to digital conversion circuit's input is connected to light buffer's output, and light buffer exports analog to digital conversion circuit to received voltage conversion to for corresponding analog voltage, the analog voltage that analog to digital conversion circuit's output connection director, analog to digital conversion circuit will be bare buffer output converts data signal into and exports the controller to, the controller is switched on or breaks off by detection circuitry's current loop according to received digital signal control. The utility model discloses technical scheme has avoided the current foldback circuit erroneous judgement, has promoted current foldback circuit's reliability.
Description
Technical field
The utility model relates to electronic technology field, particularly a kind of current foldback circuit, circuit of power factor correction and transducer air conditioning.
Background technology
At present, the current sample check processing of the circuit of power factor correction of transducer air conditioning and the overcurrent protection of Intelligent Power Module is the mode of comparator.
As shown in Figure 1; for the circuit diagram of existing current foldback circuit; this current foldback circuit is formed primarily of sampling resistor Rs, comparator A, MCU and resistance R10, R11, R12, R13, R14 and R15; the positive and negative input of comparator A receives and receives respectively through each resistance the voltage after the voltage at sampling resistor Rs two ends; then compare to export corresponding level signal and to export being turned on or off of the current circuit of the circuit that corresponding signal controlling is detected to MCU, MCU according to this level signal.Due in this current foldback circuit; the resistance of each resistance can change too long afterwards due to variation of ambient temperature or use; the voltage of comparator A input is caused to become large or reduce; thus when causing detected circuit normally to work; erroneous judgement produces overcurrent protection; or when detected circuit overcurrent, be mistaken for normal work and do not produce protection, current foldback circuit operation irregularity.In addition, the MCU of this current foldback circuit is connected by comparator with between sampling resistor Rs, does not carry out electric isolution, easily interference mutually, and causes current foldback circuit.
Utility model content
Main purpose of the present utility model is to provide a kind of current foldback circuit, is intended to avoid current foldback circuit to judge by accident, thus realizes reliable overcurrent protection accurately.
For achieving the above object, the current foldback circuit that the utility model proposes, comprise sampling resistor, light insulates enlarging device, analog to digital conversion circuit and the controller for being serially connected in the current circuit of detected circuit, the positive and negative input of described light insulates enlarging device connects the two ends of described sampling resistor respectively, to receive the input of the voltage on described sampling resistor; The output of described light insulates enlarging device connects the input of analog-digital conversion circuit as described, and described light insulates enlarging device is that corresponding analog voltage exports analog-digital conversion circuit as described to the voltage transitions received; The output of analog-digital conversion circuit as described connects described controller, and the analog voltage that described light insulates enlarging device exports is converted to digital signal and exports described controller to by analog-digital conversion circuit as described; Described controller connects described detected circuit, and the current circuit of described controller detected circuit according to the described Digital Signals received is turned on or off.
Preferably, analog-digital conversion circuit as described comprises comparator, the positive input terminal of described comparator connects the positive output end of described light insulates enlarging device, the negative input end of described comparator connects the negative output terminal of described light insulates enlarging device, and the output of described comparator is the output of analog-digital conversion circuit as described.
Preferably, analog-digital conversion circuit as described comprises comparator, the positive input terminal of described comparator connects the positive output end of described light insulates enlarging device, the negative input end of described comparator connects reference power supply, the output of described comparator is the output of analog-digital conversion circuit as described, the negative output terminal ground connection of described light insulates enlarging device.
Preferably, analog-digital conversion circuit as described comprises NPN type triode and the first resistance, the base stage of described NPN type triode connects the positive output end of described light insulates enlarging device, the collector electrode of described NPN type triode connects power supply, the emitter of described NPN type triode is through the first grounding through resistance, and the emitter of described NPN type triode is as the output of analog-digital conversion circuit as described; The negative output terminal ground connection of described light insulates enlarging device.
Preferably, analog-digital conversion circuit as described also comprises the second resistance, and the emitter of described NPN type triode connects power supply through described second resistance.
Preferably, the positive input terminal of described light insulates enlarging device connects its negative input end through an electric capacity.
Preferably, the positive and negative input of described light insulates enlarging device and the connection line of described sampling resistor are arranged side by side.
Preferably, the positive and negative input of described light insulates enlarging device and the connection line of described sampling resistor isometric.
The utility model also proposes a kind of circuit of power factor correction, comprise current foldback circuit, described current foldback circuit comprises sampling resistor, light insulates enlarging device, analog to digital conversion circuit and controller for being serially connected in the current circuit of detected circuit, the positive and negative input of described light insulates enlarging device connects the two ends of described sampling resistor respectively, to receive the input of the voltage on described sampling resistor; The output of described light insulates enlarging device connects the input of analog-digital conversion circuit as described, and described light insulates enlarging device is that corresponding analog voltage exports analog-digital conversion circuit as described to the voltage transitions received; The output of analog-digital conversion circuit as described connects described controller, and the analog voltage that described light insulates enlarging device exports is converted to digital signal and exports described controller to by analog-digital conversion circuit as described; Described controller connects described detected circuit, and the current circuit of described controller detected circuit according to the described Digital Signals received is turned on or off.
The utility model also proposes a kind of transducer air conditioning, comprise master control borad, described master control borad comprises current foldback circuit, described current foldback circuit comprises sampling resistor, light insulates enlarging device, analog to digital conversion circuit and controller for being serially connected in the current circuit of detected circuit, the positive and negative input of described light insulates enlarging device connects the two ends of described sampling resistor respectively, to receive the input of the voltage on described sampling resistor; The output of described light insulates enlarging device connects the input of analog-digital conversion circuit as described, and described light insulates enlarging device is that corresponding analog voltage exports analog-digital conversion circuit as described to the voltage transitions received; The output of analog-digital conversion circuit as described connects described controller, and the analog voltage that described light insulates enlarging device exports is converted to digital signal and exports described controller to by analog-digital conversion circuit as described; Described controller connects described detected circuit, and the current circuit of described controller detected circuit according to the described Digital Signals received is turned on or off.
Technical solutions of the utility model are by adopting light insulates enlarging device, the forceful electric power inputted from its input is converted to light current and exports from its output by the electrical-optical-electric transition form of light insulates enlarging device, and its input and output is completely isolated on electrically, then the circuit being connected to its output is isolated with the circuit being connected to its input, controller and analog to digital conversion circuit can not disturb the artificial circuit part (detected circuit and sampling resistor) be easily disturbed, and make the sampling of sampling resistor more accurate; And exporting after the conversion by light insulates enlarging device as light current, without the need to carrying out step-down by electric resistance partial pressure again, avoiding the situation causing current foldback circuit to judge by accident due to resistance conversion, more reliably.
Accompanying drawing explanation
Fig. 1 is the circuit diagram of existing current foldback circuit;
Fig. 2 is the circuit structure diagram of the utility model current foldback circuit first embodiment;
Fig. 3 is the circuit structure diagram of the utility model current foldback circuit second embodiment;
Fig. 4 is the circuit structure diagram of the utility model current foldback circuit the 3rd embodiment;
Fig. 5 is the circuit structure diagram of the utility model current foldback circuit the 4th embodiment.
Embodiment drawing reference numeral illustrates:
| Label | Title | Label | Title |
| 10 | Light insulates enlarging device | 20 | Analog to digital conversion circuit |
| 30 | Controller | Rp | Sampling resistor |
| C1 | Electric capacity | U | Comparator |
| Q | NPN type triode | R1 | First resistance |
| R2 | Second resistance | R3 | First current-limiting resistance |
| R4 | Second current-limiting resistance | R5 | 3rd current-limiting resistance |
| R6 | 4th current-limiting resistance | R7 | 5th current-limiting resistance |
| 1 | The positive input terminal of light insulates enlarging device | 2 | The negative input end of light insulates enlarging device |
| 3 | The positive output end of light insulates enlarging device | 4 | The negative output terminal of light insulates enlarging device |
| VCC | Power supply |
The realization of the utility model object, functional characteristics and advantage will in conjunction with the embodiments, are described further with reference to accompanying drawing.
Embodiment
Be described further with regard to the technical solution of the utility model below in conjunction with drawings and the specific embodiments.Should be appreciated that specific embodiment described herein only in order to explain the utility model, and be not used in restriction the utility model.
The utility model proposes a kind of current foldback circuit.
With reference to the circuit structure diagram that Fig. 2, Fig. 2 are the utility model current foldback circuit first embodiment; In the present embodiment, this current foldback circuit, comprise for being serially connected in detected circuit (such as, circuit of power factor correction) current circuit in sampling resistor Rp, light insulates enlarging device 10, analog to digital conversion circuit 20 and controller 30, the positive and negative input (being respectively label 1 and 2) of light insulates enlarging device 10 is connected the two ends of sampling resistor Rp respectively, to receive the input of the voltage on sampling resistor Rp; The output of light insulates enlarging device 10 connects the input of analog to digital conversion circuit 20, and light insulates enlarging device 10 is that corresponding analog voltage exports analog to digital conversion circuit 20 to the voltage transitions received; The output connection control device 30 of analog to digital conversion circuit 20, the analog voltage that light insulates enlarging device 10 exports is converted to digital signal and exports controller 30 to by analog to digital conversion circuit 20; Controller 30 connects detected circuit, and controller 30 is turned on or off according to the current circuit of the Digital Signals detected circuit received.
The current foldback circuit of the present embodiment is when the work of use, sample circuit is serially connected in the loop of detected circuit, thus the two ends of sampling resistor Rp form the voltage be directly proportional to the electric current in its place current circuit, light insulates enlarging device 10 just, negative input end is connected to the two ends of sampling resistor Rp, thus light insulates enlarging device 10 just, voltage difference between negative input end is the voltage at sampling resistor Rp two ends, light insulates enlarging device 10 by it just, it (is namely after being converted to light by electricity that the voltage of negative input end input carries out electrical-optical-electricity, be converted to electricity by light again) conversion after, export analog voltage signal, analog voltage signal is input in analog to digital conversion circuit 20, this analog voltage signal is converted to corresponding digital signal and exports to controller 30 by analog to digital conversion circuit 20, controller 30 determines whether overcurrent according to this digital signal size, thus control the normal work of detected circuit continuation or turn-off current loop.
The present embodiment technical scheme is by adopting light insulates enlarging device 10, the forceful electric power inputted from its input is converted to light current and exports from its output by the electrical-optical-electric transition form of light insulates enlarging device 10, and its input and output is completely isolated on electrically, then the circuit being connected to its output is isolated with the circuit being connected to its input, controller 30 and analog to digital conversion circuit 20 can not disturb the artificial circuit part (detected circuit and sampling resistor Rp) be easily disturbed, and make the sampling of sampling resistor Rp more accurate; And adopt light insulates enlarging device 10 to carry out forceful electric power in the present embodiment and turn light current, do not adopt the form of electric resistance partial pressure, avoid the situation causing current foldback circuit to judge by accident due to resistance conversion, more reliably.
The light insulates enlarging device 10 of the present embodiment preferably adopts the light insulates enlarging device of HCPL-7840 model, and HCPL-7840 type light insulates enlarging device 10, has the isolating power of 3750V, also have volume little, good linearity, low temperature coefficient, the low advantage of cost.Certainly, light insulates enlarging device 10 can also be other model.
With reference to the circuit structure diagram that Fig. 3, Fig. 3 are the utility model current foldback circuit second embodiment; Analog to digital conversion circuit 20 comprises comparator U, the positive input terminal of comparator U connects the positive output end 3 of light insulates enlarging device 10, the negative input end of comparator U connects the negative output terminal 4 of light insulates enlarging device 10, and the output of comparator U is the output of analog to digital conversion circuit 20.The voltage of light insulates enlarging device 10 positive-negative output end 4 compares to export corresponding level signal by comparator U, the height of the level signal that controller 30 exports according to comparator U, to export the control signal of current circuit shutoff and the conducting controlling detected circuit respectively.
The present embodiment also proposes another embodiment of current foldback circuit, and this embodiment scheme is only with the difference of the scheme of the second embodiment: the negative input end of comparator U is connected reference power supply, negative output terminal 4 ground connection of light insulates enlarging device 10.The present embodiment is by connecting reference power supply by the negative input end of comparator U, thus by regulating the voltage swing of reference power supply, thus when regulating comparator U to export high level, the required voltage minimum of comparator U positive input terminal, namely have adjusted the maximum current size that can flow through in the current circuit in detected circuit, thus be applicable to the circuit different to overcurrent requirement and detect, versatility is better.
With reference to the circuit structure diagram that Fig. 4, Fig. 4 are the utility model current foldback circuit the 3rd embodiment; Analog to digital conversion circuit 20 comprises NPN type triode Q and the first resistance R1, the base stage of NPN type triode Q connects the positive output end 3 of light insulates enlarging device 10, the collector electrode of NPN type triode Q connects power supply, the emitter of NPN type triode Q is through the first resistance R1 ground connection, and the emitter of NPN type triode Q is as the output of analog to digital conversion circuit 20; Negative output terminal 4 ground connection of light insulates enlarging device 10.The analog to digital conversion circuit 20 of the present embodiment is the height being controlled the level signal exporting to controller 30 by NPN type triode Q state, and then makes controller 30 control the current circuit state of detected circuit.Concrete, during detected circuit overcurrent, the voltage of light insulates enlarging device 10 positive output end 3 is greater than the conducting voltage of NPN type triode Q, NPN type triode Q conducting, thus power supply VCC is through the loop conducting of NPN type triode Q and the first resistance R1 to ground, the transmitting very high level of NPN type triode Q, namely the output of analog to digital conversion circuit 20 is high level, and the loop that controller 30 controls detected circuit disconnects; When detected circuit normally works (non-overcurrent), the voltage of the positive output end 3 of light insulates enlarging device 10 is less than the conducting voltage of NPN type triode Q, NPN type triode Q ends, thus the transmitting of NPN type triode Q very low level, controller 30 controls the current circuit not disconnecting detected circuit, and detected circuit continues normal work.
With reference to the circuit structure diagram that Fig. 5, Fig. 5 are the utility model current foldback circuit the 4th embodiment; The present embodiment is based on the technical scheme of the 3rd embodiment.The analog to digital conversion circuit 20 of the present embodiment also comprises the second resistance R2, and the emitter of NPN type triode Q connects power supply through the second resistance R2; The present embodiment meets power supply VCC by increasing by a road second resistance R2 at the emitter of NPN type triode Q, thus by regulating the resistance of the second resistance R2 to regulate the stopping potential of the emitter of NPN type triode Q, base voltage (i.e. the positive output end 3 of the light insulates enlarging device 10) needs of the NPN type triode Q made are larger just can make NPN type triode Q conducting, thus be applicable to the circuit different to overcurrent requirement and detect, versatility is better.
It should be noted that, preferably adopt NPN type triode Q to be example in the present embodiment, certain NPN type triode Q can also replace with the pipe that opens the light of other identity function.
For promoting the stability of circuit; in the current foldback circuit of above-described embodiment; also be provided with multiple current-limiting resistance; be respectively the first current-limiting resistance R3, the second current-limiting resistance R4, the 3rd current-limiting resistance R5, the 4th current-limiting resistance R6 and the 5th current-limiting resistance R7; its link position as shown in the figure, no longer describes in detail.
Further, with reference to Fig. 3 to Fig. 5, for reducing the interference of light insulates enlarging device 10 input further, the present embodiment increases by an electric capacity C1 and carries out filtering to the input of light insulates enlarging device 10, and the positive input terminal 1 of light insulates enlarging device 10 connects its negative input end 2 through an electric capacity C1.
Preferably, for increasing the antijamming capability between the positive and negative input of light insulates enlarging device 10 further, and reduce loss, the present embodiment preferably adopts the positive and negative input of light insulates enlarging device 10 and the connection line of sampling resistor Rp to be arranged side by side.And the isometric setting of connection line of the positive and negative input of preferred light isolated amplifier 10 and sampling resistor Rp.
The utility model also proposes a kind of circuit of power factor correction; this circuit of power factor correction comprises current foldback circuit; the particular circuit configurations of this current foldback circuit is with reference to above-described embodiment; because this circuit of power factor correction have employed whole technical schemes of above-mentioned all embodiments; therefore all beneficial effects that the technical scheme having above-described embodiment is equally brought, this is no longer going to repeat them.
The utility model also proposes a kind of transducer air conditioning; comprise master control borad; described master control borad comprises current foldback circuit; the particular circuit configurations of this current foldback circuit is with reference to above-described embodiment; because this transducer air conditioning have employed whole technical schemes of above-mentioned all embodiments; therefore all beneficial effects that the technical scheme having above-described embodiment is equally brought, this is no longer going to repeat them.
Should be noted that; the technical scheme of each embodiment of the present utility model can be combined with each other; but must be can be embodied as basis with those skilled in the art; when technical scheme combination occur conflicting maybe cannot realize time will be understood that the combination of this technical scheme does not exist, also not the utility model require protection range within.
The foregoing is only preferred embodiment of the present utility model; not thereby the scope of the claims of the present utility model is limited; every equivalent structure transformation utilizing the utility model specification and accompanying drawing content to do; or be directly or indirectly used in other relevant technical fields, be all in like manner included in scope of patent protection of the present utility model.
Claims (10)
1. a current foldback circuit, it is characterized in that, comprise sampling resistor, light insulates enlarging device, analog to digital conversion circuit and the controller for being serially connected in the current circuit of detected circuit, the positive and negative input of described light insulates enlarging device connects the two ends of described sampling resistor respectively, to receive the input of the voltage on described sampling resistor; The output of described light insulates enlarging device connects the input of analog-digital conversion circuit as described, and described light insulates enlarging device is that corresponding analog voltage exports analog-digital conversion circuit as described to the voltage transitions received; The output of analog-digital conversion circuit as described connects described controller, and the analog voltage that described light insulates enlarging device exports is converted to digital signal and exports described controller to by analog-digital conversion circuit as described; Described controller connects described detected circuit, and the current circuit of described controller detected circuit according to the described Digital Signals received is turned on or off.
2. current foldback circuit as claimed in claim 1; it is characterized in that; analog-digital conversion circuit as described comprises comparator; the positive input terminal of described comparator connects the positive output end of described light insulates enlarging device; the negative input end of described comparator connects the negative output terminal of described light insulates enlarging device, and the output of described comparator is the output of analog-digital conversion circuit as described.
3. current foldback circuit as claimed in claim 1; it is characterized in that; analog-digital conversion circuit as described comprises comparator; the positive input terminal of described comparator connects the positive output end of described light insulates enlarging device; the negative input end of described comparator connects reference power supply; the output of described comparator is the output of analog-digital conversion circuit as described, the negative output terminal ground connection of described light insulates enlarging device.
4. current foldback circuit as claimed in claim 1, it is characterized in that, analog-digital conversion circuit as described comprises NPN type triode and the first resistance, the base stage of described NPN type triode connects the positive output end of described light insulates enlarging device, the collector electrode of described NPN type triode connects power supply, the emitter of described NPN type triode is through the first grounding through resistance, and the emitter of described NPN type triode is as the output of analog-digital conversion circuit as described; The negative output terminal ground connection of described light insulates enlarging device.
5. current foldback circuit as claimed in claim 4, it is characterized in that, analog-digital conversion circuit as described also comprises the second resistance, and the emitter of described NPN type triode connects power supply through described second resistance.
6. as the current foldback circuit in claim 1 to 5 as described in any one, it is characterized in that, the positive input terminal of described light insulates enlarging device connects its negative input end through an electric capacity.
7. as the current foldback circuit in claim 1 to 5 as described in any one, it is characterized in that, the positive and negative input of described light insulates enlarging device and the connection line of described sampling resistor are arranged side by side.
8. current foldback circuit as claimed in claim 7, is characterized in that, the positive and negative input of described light insulates enlarging device and the connection line of described sampling resistor isometric.
9. a circuit of power factor correction, is characterized in that, comprises current foldback circuit as claimed in any of claims 1 to 8 in one of claims.
10. a transducer air conditioning, comprises master control borad, it is characterized in that, described master control borad comprises the current foldback circuit as described in any one in 1 to 8.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201520657529.0U CN204928079U (en) | 2015-08-27 | 2015-08-27 | Current foldback circuit , power factor correction circuit and transducer air conditioning |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201520657529.0U CN204928079U (en) | 2015-08-27 | 2015-08-27 | Current foldback circuit , power factor correction circuit and transducer air conditioning |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN204928079U true CN204928079U (en) | 2015-12-30 |
Family
ID=54977177
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201520657529.0U Active CN204928079U (en) | 2015-08-27 | 2015-08-27 | Current foldback circuit , power factor correction circuit and transducer air conditioning |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN204928079U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108092235A (en) * | 2017-12-08 | 2018-05-29 | 九牧智能厨卫（安徽）有限公司 | The pure hardware protection device of a kind of over current of motor or stall, method and its application |
| CN108845178A (en) * | 2018-06-15 | 2018-11-20 | 珠海格力电器股份有限公司 | A kind of over-current detection circuit and real-time detection and control method of three phase alternating current motor |
| CN111391611A (en) * | 2020-03-25 | 2020-07-10 | 广州华凌制冷设备有限公司 | Operation detection method, operation detection device, vehicle-mounted air conditioner and storage medium |
-
2015
- 2015-08-27 CN CN201520657529.0U patent/CN204928079U/en active Active
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108092235A (en) * | 2017-12-08 | 2018-05-29 | 九牧智能厨卫（安徽）有限公司 | The pure hardware protection device of a kind of over current of motor or stall, method and its application |
| CN108092235B (en) * | 2017-12-08 | 2024-04-26 | 南安九牧智能晾晒科技有限公司 | Pure hardware protection device and method for motor overcurrent or stalling and application thereof |
| CN108845178A (en) * | 2018-06-15 | 2018-11-20 | 珠海格力电器股份有限公司 | A kind of over-current detection circuit and real-time detection and control method of three phase alternating current motor |
| CN111391611A (en) * | 2020-03-25 | 2020-07-10 | 广州华凌制冷设备有限公司 | Operation detection method, operation detection device, vehicle-mounted air conditioner and storage medium |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN203026904U (en) | Over-current protection circuit and PFC (power factor correction) control circuit with same | |
| CN204928079U (en) | Current foldback circuit , power factor correction circuit and transducer air conditioning | |
| CN204515009U (en) | A kind of super low-power consumption battery voltage detection circuit | |
| CN101202470A (en) | Electric voltage equalization circuit for connecting in series super battery of capacitors | |
| CN204287446U (en) | A kind of power-fail detection circuit | |
| US20130241500A1 (en) | Charge control circuit | |
| CN103605396B (en) | Output current of converter treatment circuit and method | |
| CN102778849B (en) | Switching on and shutting down control circuit, electronic equipment and on-off control method | |
| CN204903740U (en) | Power detecting circuit | |
| CN207965722U (en) | The control circuit of PFC busbar voltages | |
| CN104634398B (en) | A kind of excitation circuit adds high pressure system and method | |
| CN207053394U (en) | A kind of overvoltage regulating circuit and pfc circuit | |
| CN207650383U (en) | A kind of transformer disconnection detection circuit of breaker | |
| CN110098811A (en) | A kind of operational amplifier and display device | |
| CN104748881A (en) | Pt1000 temperature transmitter with wide power supply range | |
| CN211426729U (en) | Fire detection alarm electric quantity detection circuit and fire detection alarm | |
| CN206756912U (en) | Voltage detecting circuit and circuit board | |
| CN109149973A (en) | Constant current output control circuit and its design method | |
| CN110867825B (en) | Overvoltage protection circuit of constant power output power supply | |
| CN209117756U (en) | Fan monitor | |
| CN208707546U (en) | Constant current output control circuit | |
| CN204405218U (en) | Wide region is powered Pt1000 temperature transmitter | |
| CN103033669B (en) | Limit peak point current-sensing circuit of switching power supply | |
| CN113189468A (en) | Health state on-line monitoring circuit and system of power device | |
| CN103097903B (en) | Method for detecting binary signal |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |