CN212572515U - Intelligent M-BUS host circuit with photoelectric isolation function - Google Patents
Intelligent M-BUS host circuit with photoelectric isolation function Download PDFInfo
- Publication number
- CN212572515U CN212572515U CN202021681968.2U CN202021681968U CN212572515U CN 212572515 U CN212572515 U CN 212572515U CN 202021681968 U CN202021681968 U CN 202021681968U CN 212572515 U CN212572515 U CN 212572515U
- Authority
- CN
- China
- Prior art keywords
- circuit
- bus
- bus host
- host
- isolation
- 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
- Dc Digital Transmission (AREA)
Abstract
The utility model belongs to the technical field of data communication, a smart M-BUS host circuit with photoelectric isolation function is disclosed, wherein a M-BUS host sending circuit is provided with a DC-DC booster circuit, a PNP triode, an NPN triode, two Schottky diodes and a plurality of capacitance components; the M-BUS host receiving circuit is provided with two operational amplifier circuits and a plurality of capacitance-resistance pieces; the bus state acquisition circuit is provided with a voltage-frequency conversion module; the signal isolation circuit is connected with the main control unit, and the main control unit is provided with a plurality of opto-couplers and a plurality of capacitance resistors. The utility model discloses have stronger interference killing feature, can gather M-BUS BUS state in real time to dynamic adjustment M-BUS host computer receiving characteristic, in order to adapt to the different M-BUS in scene and follow the electrical characteristic of machine, simultaneously the utility model discloses have better dynamic response ability, to single follow the machine collection or many follow the machine collection all have good adaptability, improved the reliability and the accuracy of collection.
Description
Technical Field
The utility model belongs to the technical field of the data communication, especially, relate to an intelligence M-BUS host computer circuit with photoelectric isolation function.
Background
At present: in order to promote the development of the national 'smart city', the existing channel resources are utilized to construct a 'water, electricity, gas and heat' four-meter automatic acquisition application system, which becomes a key task, and M-BUS is used as a master-slave half-duplex communication system, has the advantages of low cost, convenience in power supply, no polarity, long transmission distance and the like, and is widely applied to reading and copying water meters, gas meters and heat meters.
At present, the existing M-BUS host transceiving control circuit mainly adopts 36V or 12V power supply and can be realized by alternating current power supply. The meter installation position of the existing building is far away from a building and is dispersed, more and more data acquisition devices adopt a battery power supply scheme, and meanwhile, the traditional M-BUS host circuit cannot sense parameters such as the number and the state of slave nodes and cannot meet the increasingly intelligent meter reading requirement. Meanwhile, due to the difference of the electrical characteristics of the field M-BUS slave machines, the existing circuit cannot meet the requirement of the diversity of the slave machines. Therefore, the demand of the M-BUS host circuit which can be powered by a lithium battery and is more intelligent and more adaptive is more obvious.
Through the above analysis, the problems and defects of the prior art are as follows:
(1) the existing M-BUS host transceiving control circuit mainly adopts 36V or 12V power supply and can be realized only by AC power supply.
(2) The traditional M-BUS host circuit cannot sense parameters such as the number and the state of slave nodes, has poor dynamic response capability and anti-interference capability, and cannot meet the increasingly intelligent meter reading requirement.
(3) Due to the difference of the electrical characteristics of the field M-BUS slave machines, the existing circuit cannot meet the requirement of the diversity of the slave machines.
The difficulty in solving the above problems and defects is: the existing M-BUS host circuit is designed according to the electrical characteristics of standard slaves, and a large number of nonstandard slaves exist in the market, so that communication failure is caused. And the M-BUS current cannot be quantized. The current M-BUS host sending circuit is divided into two types, one type adopts double power supplies to realize the adjustment of BUS level, but the cost is high, the structure is complex, the reliability is poor, and the application is less; in addition, a single power supply is adopted, the LDO is used for regulating the bus voltage, due to the characteristics of the LDO, when the bus level is changed from high to low, the dynamic response is poor, particularly when the load is light, the problem that the minimum load is increased can be solved, the efficiency is not high, and particularly when the power supply is provided by a battery, the service life of the battery is indirectly shortened.
The significance of solving the problems and the defects is as follows: the utility model discloses can intelligent recognition adjust the receiving threshold value from the electrical characteristic of machine, improve the dynamic response characteristic of circuit, greatly increased the adaptability of circuit, improved the success rate and the energy conversion efficiency of copying.
SUMMERY OF THE UTILITY MODEL
To the problem that prior art exists, the utility model provides an intelligence M-BUS host computer circuit with photoelectric isolation function.
The utility model discloses a realize like this, an intelligence M-BUS host computer circuit with optoelectronic isolation function is provided with:
the system comprises an M-BUS host sending circuit, an M-BUS host receiving circuit, a BUS state acquisition circuit and a signal isolation circuit;
the M-BUS host sending circuit is provided with a DC-DC booster circuit, a PNP triode, an NPN triode, two Schottky diodes and a plurality of capacitance resistors; the M-BUS host receiving circuit is provided with two operational amplifier circuits and a plurality of capacitance-resistance pieces; the bus state acquisition circuit is provided with a voltage-frequency conversion module, and the signal isolation circuit is provided with a plurality of opto-couplers and a plurality of capacitance-resistance pieces; the signal isolation circuit is connected with the main control unit.
Further, the input end of the M-BUS host sending circuit is connected with the signal isolation circuit, and the output end of the M-BUS host sending circuit is connected with the M-BUS BUS.
Furthermore, the input end of the M-BUS host receiving circuit is connected with the M-BUS BUS, and the output end of the M-BUS host receiving circuit is connected with the signal isolation circuit.
Furthermore, the input end of the BUS state acquisition circuit is connected with an M-BUS BUS through a sampling resistor, the output end of the BUS state acquisition circuit is connected with the signal isolation circuit, and one end of R14 in the circuit is respectively connected into the two parts of circuits.
Furthermore, the voltage-frequency conversion module is communicated with an input end of a first optical coupling circuit of the signal isolation circuit.
Combine foretell all technical scheme, the utility model discloses the advantage that possesses and positive effect are:
the utility model provides a M-BUS host computer transmitting circuit can adopt lithium battery powered, realizes the transmission of BUS data through the output level of adjusting DC-DC that steps up, and fig. 5 is level oscillogram when traditional M-BUS host computer circuit underloads, and fig. 6 is the utility model discloses level oscillogram when the circuit underloads. The contrast reachs the utility model discloses can realize the quick adjustment of bus level, have good dynamic response characteristic, have that conversion efficiency is high, adaptability is good, advantage with low costs.
The M-BUS receiving circuit utilizes the PWM circuit, and can dynamically adjust the receiving characteristic of the M-BUS host to adapt to the electrical characteristics of different types of M-BUS slaves. And the rear end adopts a mode of an operational amplifier comparator to realize the receiving and demodulation of the signals of the M-BUS slave. The electrical characteristics are shown in table 1 by testing different M-BUS slaves currently on the market. Therefore, the existing M-BUS circuit can only communicate with the slave 1, the slave 2 and the slave 4, and the utility model can communicate with all the slaves in the watch.
TABLE 1M-BUS Meter Electrical characteristics
The M-BUS state acquisition circuit converts M-BUS current into a voltage signal through the sampling resistor, and the signal is converted into a pulse signal through the voltage-frequency conversion circuit and transmitted to the main control chip through the signal isolation circuit. The main control chip can acquire the accurate current value and the change condition of the M-BUS according to the frequency of the signal, and can study and judge problems such as overcurrent, meter circuit disconnection, meter power consumption abnormity and the like.
The signal isolation circuit adopts an optical coupler to completely isolate the communication side from the system side, so that the anti-interference capability of the system is improved.
The utility model discloses can use the power supply of lithium cell 3.6v, keep apart communication side and system side through the opto-coupler, have stronger interference killing feature. Can gather M-BUS BUS state in real time to dynamic adjustment M-BUS host computer receiving characteristic to the electric characteristic of the different M-BUS slaves in adaptation scene, simultaneously the utility model discloses have better dynamic response ability, to single from the computer collection or many from the computer collection all have good adaptability, improved the reliability and the accuracy and the energy conversion efficiency of gathering.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments of the present application will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present application, and it is obvious for those skilled in the art that other drawings can be obtained from the drawings without creative efforts.
Fig. 1 is a schematic diagram of the circuit connection of the intelligent M-BUS host with photoelectric isolation function provided by the embodiment of the present invention.
Fig. 2 is a circuit diagram of the M-BUS host transmission circuit provided by the embodiment of the present invention.
Fig. 3 is a circuit diagram of the M-BUS host receiving circuit provided by the embodiment of the present invention.
Fig. 4 is a circuit diagram of a bus state acquisition circuit and a signal isolation circuit according to an embodiment of the present invention.
FIG. 5 is a waveform diagram of the level of the conventional M-BUS host circuit under light load.
Fig. 6 is a waveform diagram of the level when the circuit of the present invention is lightly loaded.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
To the problem that prior art exists, the utility model provides an intelligence M-BUS host computer circuit with photoelectric isolation function, it is following to combine the figure to do detailed description to the utility model discloses.
As shown in FIG. 1, the embodiment of the utility model provides an intelligence M-BUS host computer circuit with photoelectric isolation function comprises M-BUS host computer transmitting circuit, M-BUS host computer receiving circuit, BUS state acquisition circuit and signal isolation circuit.
As shown in FIG. 2, the M-BUS host sending circuit is composed of a U1-boost DC-DC, a Q1-PNP triode, a Q2-NPN triode, a D1, a D2-Schottky diode and a part of resistance-capacitance element. The downlink data from the M-BUS host to the slave is realized by controlling the level of the BUS, and the specific principle is as follows: when the MBUS _ TX sends a high level, an NPN triode Q2 is conducted, a resistor R2 and a resistor R3 are connected in parallel, and the output voltage of the boosted DC-DC U1 is
Wherein VREFIn order to boost the reference voltage of DC-DC, the base voltage of PNP triode Q1 is higher than the emitter voltage due to the tube voltage drop of D2 Schottky diode, Q1 is not conducted, and the output voltage of M-BUS BUS is Vmark-Vdiode1，Vdiode1Is the forward conduction voltage drop of diode D2. When MBUS _ TX sends low level, the transistor Q2 is cut off, R2 is connected with R3 in parallel, and the U1 boosting DC-DC output voltage is changed into
At this time, due to the existence of the equivalent capacitor of the C2 and the BUS, the voltage of the negative electrode of the D2 is higher than the voltage of the positive electrode, the D2 is temporarily cut off, the voltage of the emitter of the Q1 is higher than the voltage of the base, the Q1 is conducted, the voltage of the capacitor C2 and the equivalent capacitor of the BUS is quickly discharged to the ground through the triode Q1 and the resistor R5 until the triode Q1 is turned off, the D2 is conducted again, and the output voltage of the M-BUS BUS is Vspace-Vdiode2，Vdiode2Is the forward conduction voltage drop of diode D2. The quick jump from the high level to the low level of the M-BUS is realized, and the problem of poor low level response of the BUS when the number of slave machines of the M-BUS is small is solved.
The utility model provides a M-BUS host computer transmitting circuit can adopt lithium cell power supply, realizes the transmission of BUS data through the output level of adjusting DC-DC that steps up, the utility model discloses can realize the quick adjustment of BUS level, have good dynamic response characteristic, have conversion efficiency height, adaptability is good, advantage with low costs.
As shown in FIG. 3, the M-BUS host receiving circuit is composed of U2, U3-operational amplifier and partial RC. The data sent by the slave is realized by current modulation, and the bus slave node normally works and consumes the load current ImarkLogic "1" when R14 changes ImarkConversion of current signal into voltage signal Vimark＝R14*ImarkAnd is connected to the inverting terminal of the U2 operational amplifier through R13, when logic '0' is sent, according to the M-BUS protocol, the node will additionally draw 10-20mA pulse current from the M-BUS BUS to form IspaceSo that the voltage at the inverting terminal of the U2 operational amplifier becomes Vispace＝R14*Ispace. The master control chip sends pulse signals with adjustable certain frequency and pulse width, the pulse signals are connected to a positive phase end of U3 after optical coupling isolation, VCC _ MBUS is connected to a negative phase end of U3 through the partial voltage of R21 and R22, the voltage of the negative phase end of the operational amplifier is VCC _ MBUS of 1/2, therefore, a 1 pin of the operational amplifier U3 can output a pulse signal with the same frequency and phase as a 3 pin, and the pulse signal forms reference voltage V through three-stage filtering composed of R9, R10, R11, C3, C4 and C5RThe pulse signal duty ratio is VCC _ MBUS, the pulse signal duty ratio is input into the in-phase end of the U2 operational amplifier through R8, and the duty ratio of the pulse signal can be adjusted according to actual conditions to ensure that V isimark<VR<VispaceTherefore, when the bus current is ImarkTime, operational amplifier non-inverting terminal voltage VRGreater than the inverting terminal VimarkThe operational amplifier 1 pin outputs high level when the bus current is IspaceTime, operational amplifier non-inverting terminal voltage VRSmaller than the inverting terminal VispaceThe pin 1 of the operational amplifier outputs low level, and the level output by the pin 1 of the operational amplifier realizes the data receiving through a driving signal isolation circuit. The electrical performance of the slave machine in the market does not completely accord with the M-BUS protocol, the pulse current drawn from the M-BUS BUS is not equal from 5mA to 70mA, the added value of the pulse current when the meter replies data of 0 can be intelligently acquired due to the existence of the state acquisition circuit, and the duty ratio of the pulse signal is intelligently adjusted by the main control chip according to the added value of the pulse currentAdjusting VRAnd thus better adaptability is obtained.
The M-BUS receiving circuit utilizes the PWM circuit, and can dynamically adjust the receiving characteristic of the M-BUS host to adapt to the electrical characteristics of different types of M-BUS slaves. And the rear end adopts a mode of an operational amplifier comparator to realize the receiving and demodulation of the signals of the M-BUS slave.
As shown in fig. 4, the state acquisition circuit is composed of a voltage-to-frequency conversion module, and the signal isolation circuit is composed of O1, O2, O3, O4-optical couplers and partial resistors and capacitors. When the M-BUS BUS starts to output, the static working current of the slave is converted into a voltage signal V through R14 in the receiving circuit of the M-BUS hostimarkThe voltage-frequency conversion module is connected to an input pin of the voltage-frequency conversion module, converts a voltage signal into a corresponding frequency signal, is connected with a 1 pin of an O1 optical coupler and transmits the frequency signal to the rear end of the optical coupler, and R15 is a pull-up resistor. The main control chip can obtain the current value I of the static consumption of the bus by collecting the frequency and the voltage-frequency conversion proportion K of the pulse signalmarkBy analyzing the current value and combining the total number a of the acquisition meter in the acquisition terminal, the current I statically consumed by each slave node can be calculated1＝ImarkA, when ImarkWhen the abnormity is reduced, the damage of the slave node or the abnormity of the line can be deduced by combining the meter reading condition, and when I ismarkWhen the abnormity is increased, the aging of the slave node or short-circuit overcurrent can be deduced by combining with a judgment threshold value. The state acquisition circuit can not only provide data support for intelligently and dynamically adjusting the M-BUS receiving characteristic, but also intelligently study and judge BUS abnormity, and the reliability and intelligence of acquisition are improved. The main control chip sends MBUS _ PWM _ S to drive the optocoupler to form MBUS-PWM, the main control chip sends MBUS _ TX _ S to drive the optocoupler to form MBUS _ TX, and an MBUS bus receiving signal MBUS _ RX drives the optocoupler to form MBUS _ RX _ S. The signal isolation circuit can effectively protect a system side circuit, improve the anti-interference capability and improve the operation stability.
The M-BUS state acquisition circuit converts M-BUS current into a voltage signal through the sampling resistor, and the signal is converted into a pulse signal through the voltage-frequency conversion circuit and transmitted to the main control chip through the signal isolation circuit. The main control chip can acquire the accurate current value and the change condition of the M-BUS according to the frequency of the signal, and can study and judge problems such as overcurrent, meter circuit disconnection, meter power consumption abnormity and the like.
The signal isolation circuit adopts an optical coupler to completely isolate the communication side from the system side, so that the anti-interference capability of the system is improved.
In the description of the present invention, "a plurality" means two or more unless otherwise specified; the terms "upper", "lower", "left", "right", "inner", "outer", "front", "rear", "head", "tail", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are merely for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be covered within the protection scope of the present invention by those skilled in the art within the technical scope of the present invention.
Claims (5)
1. The utility model provides an intelligence M-BUS host computer circuit with optoelectronic isolation function which characterized in that, intelligence M-BUS host computer circuit with optoelectronic isolation function is provided with:
the system comprises an M-BUS host sending circuit, an M-BUS host receiving circuit, a BUS state acquisition circuit and a signal isolation circuit;
the M-BUS host sending circuit is provided with a DC-DC booster circuit, a PNP triode, an NPN triode, two Schottky diodes and a plurality of capacitance resistors; the M-BUS host receiving circuit is provided with two operational amplifier circuits and a plurality of capacitance-resistance pieces; the bus state acquisition circuit is provided with a voltage-frequency conversion module, and the signal isolation circuit is provided with a plurality of opto-couplers and a plurality of capacitance-resistance pieces; the signal isolation circuit is connected with the main control unit.
2. The intelligent M-BUS host circuit with photoelectric isolation of claim 1, wherein the input of the M-BUS host transmitting circuit is connected with the signal isolation circuit, and the output of the M-BUS host transmitting circuit is connected with the M-BUS BUS.
3. The intelligent M-BUS host circuit with optoelectronic isolation of claim 1, wherein the input of the M-BUS host receiver circuit is connected to the M-BUS BUS, and the output of the M-BUS host receiver circuit is connected to the signal isolation circuit.
4. The intelligent M-BUS host circuit with photoelectric isolation of claim 1, wherein the input terminal of the BUS state acquisition circuit is connected with the M-BUS BUS through a sampling resistor, and the output terminal of the BUS state acquisition circuit is connected with the signal isolation circuit.
5. The intelligent M-BUS host circuit with optoelectronic isolation of claim 1, wherein the voltage to frequency conversion module is in communication with an input of a first optocoupler circuit of the signal isolation circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021681968.2U CN212572515U (en) | 2020-08-13 | 2020-08-13 | Intelligent M-BUS host circuit with photoelectric isolation function |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202021681968.2U CN212572515U (en) | 2020-08-13 | 2020-08-13 | Intelligent M-BUS host circuit with photoelectric isolation function |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN212572515U true CN212572515U (en) | 2021-02-19 |
Family
ID=74628013
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202021681968.2U Active CN212572515U (en) | 2020-08-13 | 2020-08-13 | Intelligent M-BUS host circuit with photoelectric isolation function |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN212572515U (en) |
-
2020
- 2020-08-13 CN CN202021681968.2U patent/CN212572515U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111884646A (en) | Intelligent M-BUS host circuit with photoelectric isolation function and control method | |
| WO2022041890A1 (en) | Switching value acquisition circuit and method | |
| CN206321756U (en) | A kind of power-fail detection circuit and switching power circuit | |
| CN103313003A (en) | Standby control circuit and television set | |
| CN109039092A (en) | A kind of voltage detecting circuit and the reversible transducer using the circuit | |
| CN212572515U (en) | Intelligent M-BUS host circuit with photoelectric isolation function | |
| CN201937907U (en) | LED driving power supply for train | |
| CN201812008U (en) | Detection circuit for relay protection device | |
| CN203929855U (en) | A kind of servo control mechanism cell voltage test circuit | |
| CN208890651U (en) | A kind of voltage detecting circuit and the reversible transducer using the circuit | |
| CN206975450U (en) | A kind of mbus circuits of opto-electrical direct reader | |
| CN101694995B (en) | Passive RS232-485 signal converter | |
| CN108108318B (en) | TTL changes MBUS communication terminal | |
| CN207458043U (en) | Inexpensive M-BUS host communications circuit | |
| CN110519141A (en) | A kind of slave communicating circuit and communication device | |
| CN215180472U (en) | Mixed AC/DC signal measurement system based on bus communication mode | |
| CN114221321A (en) | Voltage polarity automatic switching circuit and method of direct-current power supply | |
| CN220108003U (en) | Power supply circuit, main station circuit and communication system of BUS BUS | |
| CN218549500U (en) | High-voltage isolation communication circuit | |
| CN215983128U (en) | Current loop communication receiving circuit, communication circuit and air conditioner | |
| CN220436734U (en) | AC/DC adapter plate | |
| CN216016887U (en) | Long-distance wireless passthrough circuit of low-power consumption based on loRa technique | |
| CN203519751U (en) | Remote control loop detection circuit for load control terminal | |
| CN216901648U (en) | High-speed RS-485 communication circuit applied to intelligent electric energy meter | |
| CN216649530U (en) | Information acquisition remote communication terminal |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |