CN218416386U - Communication circuit and electric energy meter - Google Patents
Communication circuit and electric energy meter Download PDFInfo
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- CN218416386U CN218416386U CN202222919050.2U CN202222919050U CN218416386U CN 218416386 U CN218416386 U CN 218416386U CN 202222919050 U CN202222919050 U CN 202222919050U CN 218416386 U CN218416386 U CN 218416386U
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Abstract
The utility model discloses a communication circuit and electric energy meter. The circuit comprises a 485 chip, a first circuit, a second circuit, a third circuit and a first resistor; the first circuit comprises a first triode which is turned off when a first pin of the 485 chip outputs a high-level signal and is turned on when a low-level signal is output; the second circuit comprises a second triode which is switched off when the data transmitting port outputs a high level signal and is switched on when the data transmitting port outputs a low level signal. The utility model discloses an at opto-coupler device output termination triode, utilize the switching characteristic of triode, the threshold value that the triode was opened and is turn-offed is lower promptly, only needs the partly of the optical coupling output end wave form rise decline along required time can satisfy the action requirement among the prior art, can provide standard high-low level data after the action, so shortened the time that the wave form rises and falls to increaseed the effective pulse width of data, and then improved communication stability.
Description
Technical Field
The utility model relates to a power electronic technology field especially relates to a communication circuit and electric energy meter.
Background
The photoelectric coupler mainly comprises three parts: light emission, light reception and signal amplification. The light emitting portion is mainly constituted by a light emitting device. The input end of the photoelectric coupler is electrified with a signal to make the luminous source emit light, the intensity of the light depends on the magnitude of the exciting current, when the light irradiates on the light receiver packaged together, a photocurrent is generated due to the photoelectric effect and is led out from the output end of the light receiver, and thus, the electro-optic-electrical conversion is realized.
Most of the existing digital display meters and electric meter products only adopt the characteristics of an optical coupler for communication data transmission, and the situations of large delay, short data pulse width and poor communication stability of a 485 communication circuit communication transceiving end exist.
SUMMERY OF THE UTILITY MODEL
Based on the problem, the utility model provides a communication circuit and electric energy meter to 485 communication circuit communication transceiver end time delay is great among the solution prior art, data pulse width is short, the not good problem of communication stability.
In a first aspect, the utility model discloses a following technical scheme: a communication circuit comprises a 485 chip, a first circuit, a second circuit, a third circuit and a first resistor;
the first circuit is connected with a first pin of the 485 chip;
the output end of the second circuit is connected with the second pin and the third pin of the 485 chip;
a third port of the third circuit is connected with a fourth pin of the 485 chip;
the first end of the first resistor is connected with the first port of the second circuit, and the second end of the first resistor is connected with the third port of the third circuit and grounded;
a fourth port of the third circuit is connected with a second port of the second circuit;
the first circuit comprises a first triode, the first triode is turned off when a first pin of the 485 chip outputs a high-level signal, and is turned on when the first pin of the 485 chip outputs a low-level signal;
the second circuit comprises a second triode which is turned off when a data sending port outputs a high level signal and is turned on when the data sending port outputs a low level signal.
Optionally, the first triode is an NPN-type triode.
Optionally, the second triode is a PNP type triode.
Optionally, the first circuit further includes a first optocoupler, a second resistor, a third resistor, a fourth resistor, and a fifth resistor;
a first port of the first optocoupler is connected with a first end of the second resistor; a third port of the first optocoupler is connected with a first end of the fourth resistor and a first end of the fifth resistor; a fourth port of the first optocoupler is connected with a first end of the third resistor;
the base electrode of the first triode is connected with the second end of the fourth resistor; the emitter of the first triode is connected with the second end of the fifth resistor and is grounded; the collector of the first triode is connected with the data receiving port;
the second end of the second resistor is connected with a first power supply;
and the first end of the third resistor is connected with a second power supply, and the second end of the third resistor is connected with the data receiving port.
Optionally, the second circuit further includes a sixth resistor and a seventh resistor;
the base electrode of the second triode is connected with the first end of the seventh resistor; an emitting electrode of the second triode is connected with a first end of the sixth resistor; a collector of the second triode is connected with the second pin and the third pin of the 485 chip;
and the second end of the sixth resistor and the second end of the seventh resistor are connected with the fourth port of the third circuit.
Optionally, the third circuit includes a second optical coupler and an eighth resistor;
a first port of the second optocoupler is connected with a first end of the eighth resistor; a second port of the second optical coupler is connected with a data sending port;
and the second end of the eighth resistor is connected with a second power supply.
Optionally, the circuit further includes a ninth resistor, a tenth resistor, and a bidirectional zener diode;
a fifth port of the 485 chip is grounded; a sixth port of the 485 chip is connected with the first end of the ninth resistor and the first end of the bidirectional voltage stabilizing diode; a seventh port of the 485 chip is connected with the first end of the tenth resistor and the second end of the bidirectional voltage stabilizing diode; an eighth port of the 485 chip is connected with a first power supply;
a second end of the ninth resistor is connected with the first power supply;
a second end of the tenth resistor is grounded.
Optionally, the bidirectional zener diode is configured to control a voltage to ground of the sixth port of the 485 chip and a voltage to ground of the seventh port of the 485 chip within a preset range.
Optionally, the circuit further includes a capacitor, and the capacitor is connected to a power supply connected to an eighth pin of the 485 circuit; the other end of the capacitor is grounded.
Optionally, the distance between the capacitor and the power pin connected to the capacitor is within a preset range.
In a second aspect, the utility model discloses an electric energy meter, electric energy meter includes any one of the aforesaid circuit. The utility model provides a communication circuit and electric energy meter. The circuit comprises a 485 chip, a first circuit, a second circuit, a third circuit and a first resistor; the first circuit is connected with a first pin of the 485 chip; the output end of the second circuit is connected with the second pin and the third pin of the 485 chip; a third port of the third circuit is connected with a fourth pin of the 485 chip; the first end of the first resistor is connected with the first port of the second circuit, and the second end of the first resistor is connected with the third port of the third circuit and grounded; a fourth port of the third circuit is connected with a second port of the second circuit; the first circuit comprises a first triode, the first triode is turned off when a first pin of the 485 chip outputs a high-level signal, and is turned on when the first pin of the 485 chip outputs a low-level signal; the second circuit comprises a second triode which is turned off when a data sending port outputs a high level signal and is turned on when the data sending port outputs a low level signal.
Compared with the prior art, the utility model discloses following beneficial effect has:
the utility model discloses an at opto-coupler device output termination triode, utilize the on-off characteristic of triode, the threshold value that the triode was opened and is turn-offed is lower promptly, only needs among the prior art that some of opto-coupler output end wave form rising fall edge required time can satisfy the action requirement, can provide standard high-low level data after the action, so shortened the time that the wave form rises and falls to increaseed the effective pulsewidth of data, and then improved communication stability.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive exercise.
Fig. 1 is a schematic structural diagram of a 485 communication circuit in the prior art;
FIG. 2 is a diagram illustrating a data rising and falling edge change process in the prior art;
fig. 3 is a communication circuit diagram according to an embodiment of the present invention;
fig. 4 is a schematic diagram of a 485 circuit provided in an embodiment of the present invention;
fig. 5 is a schematic structural diagram of a first circuit 100 according to an embodiment of the present invention;
fig. 6 is a schematic structural diagram of a second circuit 200 according to an embodiment of the present invention;
fig. 7 is a schematic structural diagram of a third circuit 300 according to an embodiment of the present invention;
fig. 8 is a schematic diagram illustrating a process of connecting a transistor to an output end of an optocoupler device in a rising edge and a falling edge according to an embodiment of the present invention;
fig. 9 is a schematic view of a connection structure between 5 th and 8 th ports of a 485 chip according to an embodiment of the present invention.
Detailed Description
As described above, the current photocouplers are mainly composed of three parts: light emission, light reception and signal amplification. The light emitting portion is mainly constituted by a light emitting device. The input end of the photoelectric coupler is electrified with a signal to make the luminous source emit light, the intensity of the light depends on the magnitude of the exciting current, when the light irradiates on the light receiver packaged together, a photocurrent is generated due to the photoelectric effect and is led out from the output end of the light receiver, and thus, the electro-optic-electrical conversion is realized.
Most of the existing digital display meters and electric meter products only adopt the characteristics of an optical coupler to transmit communication data, a 485 communication circuit is taken as an example, referring to fig. 1, fig. 1 is a schematic structural diagram of the 485 communication circuit in the prior art, an output end of an optical coupler device is connected with a pull-up resistor and a pull-down resistor in the circuit diagram, the rising and falling edges of data are slow, the time is long, and the problems of large delay, short data pulse width and poor communication stability of a 485 communication transceiving end are caused. In the prior art, a data rising and falling edge change process is shown in fig. 2, for example, when a communication waveform is 1200bps, when a data transmission port (TXD 485 port) is changed from a high level to a low level, that is, after an optocoupler receiving end receives standard pulse width data, signals of ports DE,/RE need to pass for a period of time, for example, 100us, to be changed from the low level to the high level, that is, time consumed by a rising edge is long, so that a data pulse width is shortened, and further, communication stability is poor. The parameters in the figure are only exemplary parameters, and do not limit the values of the parameters involved in the figure.
In view of this, the utility model provides a communication circuit, through at opto-coupler device output termination triode, utilize the switching characteristic of triode, the threshold value that the triode was opened and was turn-offed is lower promptly, only needs the partly of the last required time of the rising fall edge of opto-coupler output end wave form in the prior art can satisfy the action requirement, can provide the high-low level data of standard after the action, so can shorten the time that the wave form rises and falls to increase the effective pulse width of data, and then improve communication stability.
In order to make the technical solution of the present invention better understood, the technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts all belong to the protection scope of the present invention.
Referring to fig. 3, fig. 3 is a communication circuit diagram provided in an embodiment of the present invention, where the circuit includes a 485 chip U5, a first circuit 100, a second circuit 200, a third circuit 300, and a first resistor R18;
the first circuit 100 is connected with a first pin RO of the 485 chip U5;
the output end of the second circuit 200 is connected with the second pin/RE and the third pin DE of the 485 circuit U5;
a third port of the third circuit 300 is connected to a fourth pin DI of the 485 chip U5;
a first end of the first resistor R18 is connected to the first port of the second circuit 200, and a second end of the first resistor R18 is connected to the third port of the third circuit 300 and grounded;
the fourth port of the third circuit 300 is connected to the second port of the second circuit 200;
the first circuit 100 includes a first triode Q1, and the first triode Q1 is turned off when a first pin RO of the 485 chip U5 outputs a high level signal, and is turned on when the first pin RO of the 485 chip U5 outputs a low level signal;
the second circuit 200 includes a second transistor Q2, and the second transistor Q2 is turned off when a data transmission port outputs a high level signal and is turned on when the data transmission port outputs a low level signal.
Compare behind the opto-coupler device output current that flows among the prior art, through last pull-down resistance, then need through whole rising after the decline edge, just can produce the high low level data that can utilize, the utility model discloses an at opto-coupler device output termination triode, utilize the switching characteristic of triode, the threshold value that the triode was opened and is turn-offed is lower promptly, only needs the partly of the optical-coupler output waveform rise decline edge required time among the prior art can satisfy the action requirement, can provide the high low level data of standard after the action, so shortened the time that the waveform rises and descends to data effective pulse width has been strengthened, and then communication stability has been improved.
The following describes the implementation process of the embodiment of the present invention in detail with reference to the circuit diagram.
Referring to fig. 4, fig. 4 is a schematic diagram of a 485 circuit according to an embodiment of the present invention, where fig. 1 shows specific devices and connection relations included in the first circuit 100, the second circuit 200, and the third circuit 300, and first introduces specific structures and connection relations of the first circuit 100, the second circuit 200, and the third circuit 300:
referring to fig. 5, fig. 5 is a schematic structural diagram of a first circuit 100 according to an embodiment of the present invention, where the first circuit 100 includes a first triode Q1, a first optocoupler U4, a second resistor R11, a third resistor R10, a fourth resistor R15, and a fifth resistor R16;
a first port of the first optocoupler U4 is connected with a first end of the second resistor R11; a third port of the first optocoupler U4 is connected to a first end of the fourth resistor R15 and a first end of the fifth resistor R16; a fourth port of the first optocoupler U4 is connected with a first end of the third resistor R10;
the base electrode B of the first triode Q1 is connected with the second end of the fourth resistor R15; an emitter E of the first triode Q1 is connected with the second end of the fifth resistor R16 and is grounded; a collector C of the first triode Q1 is connected with a data receiving port (RXD 485 port);
the second end of the second resistor R11 is connected with a first power supply 485 VCC;
a first end of the third resistor R10 is connected to VDD, and a second end of the third resistor R10 is connected to the data receiving port.
Referring to fig. 6, fig. 6 is a schematic structural diagram of a second circuit 200 according to an embodiment of the present invention, where the second circuit 200 includes a second triode Q2, a sixth resistor R17, and a seventh resistor R23;
a base electrode B of the second triode Q2 is connected with a first end of the seventh resistor R23; an emitter E of the second triode Q2 is connected with a first end of the sixth resistor R17; a collector C of the second triode Q2 is connected with a second pin/RE and a third pin DE of the 485 chip;
a second end of the sixth resistor R17 and a second end of the seventh resistor R23 are connected to the fourth port of the third circuit 300.
Referring to fig. 7, fig. 7 is a schematic structural diagram of a third circuit 300 according to an embodiment of the present invention, where the third circuit 300 includes a second optical coupler U6 and an eighth resistor R22; a first port of the second optocoupler is connected with a first end of the eighth resistor; a second port of the second optical coupler U6 is connected with a data sending port;
a second end of the eighth resistor R22 is connected to the second power supply VDD.
After the specific structures and connection relations of the circuit diagrams are introduced, the working process of the 485 circuit shown in the following fig. 4 is introduced: when no data processing is performed, the 485 chip sets the/RE port to be at a low level through the resistor R18, and the 485 chip is in a data receiving state. After receiving host computer data through A, B mouth, when RO port output high level data, U4 opto-coupler device input emitting diode does not have the current, and U4 opto-coupler device output phototriode does not have the current and passes through, triode Q1 shutoff, and RXD485 end is pulled up to the high level by R10 resistance. When the RO port outputs low level data, the current flows through the light emitting diode at the input end of the U4 optical coupler device, and meanwhile, the current flows through the photosensitive triode at the output end of the U4 optical coupler device, flows through the R15 resistor, the triode Q1 is turned on, and the RXD485 end is pulled to the low level. After the main chip receives the data through the data receiving port, the response data is sent through the data sending port. When the data transmission port outputs high level data, the light emitting diode at the input end of the U6 optocoupler has no current, the phototriode at the output end of the U6 optocoupler has no current and passes through, the triode Q2 is turned off, the DE end is pulled down to a low level by the R18 resistor, and the ports A and B output high levels by default. When data transmission port output low level data, the current flows through U6 opto-coupler device input emitting diode, and the photosensitive triode of U6 opto-coupler device output passes through the current simultaneously, flows through R23 resistance, opens triode Q2, and the DE end is pulled up to the high level, sends the low level data of DI port to the AB end. Thus, a complete data transceiving process is completed.
The embodiment of the utility model provides an in first triode Q1 adopts NPN type triode, and second triode Q2 adopts PNP type triode, utilizes the switching characteristic of triode, and the threshold value that the triode was opened and is turn-offed is lower promptly, only needs opto-coupler device output waveform to rise and descend along the partly of required time can satisfy the action requirement, can provide the high low level data of standard after the action. I.e., shortening the rise and fall time of the waveform and increasing the effective pulse width of the data. Fig. 8 shows a schematic diagram of a rising edge and a falling edge process after the output end of the optocoupler is connected with the triode, and because the threshold value of the triode is relatively low, after the level output by the data sending port is changed from a high level to a low level, only 10us is needed to change the DE/RE port from the low level to the high level, so that the time for level conversion is reduced, the pulse width is increased, and the communication is more stable.
Compare behind the opto-coupler device output current that flows among the prior art, through last pull-down resistance, then need through whole rising after the decline edge, just can produce the high low level data that can utilize, the utility model discloses an at opto-coupler device output termination triode, utilize the switching characteristic of triode, the threshold value that the triode was opened and is turn-offed is lower promptly, only needs the partly of the optical-coupler output waveform rise decline edge required time among the prior art can satisfy the action requirement, can provide the high low level data of standard after the action, so shortened the time that the waveform rises and descends to data effective pulse width has been strengthened, and then communication stability has been improved.
Further, in an alternative embodiment of the present invention, the circuit further includes a ninth resistor R62, a tenth resistor R64, and a bidirectional zener diode TVS1, and the connection relationship of the components is shown in fig. 9,
a fifth port GND of the 485 chip is grounded; a sixth port a of the 485 chip is connected with the first end of the ninth resistor R62 and the first end of the bidirectional voltage regulator diode TVS 1; a seventh port B of the 485 chip is connected to the first end of the tenth resistor R64 and the second end of the bidirectional zener diode TVS 1; an eighth port of the 485 chip is connected with a first power supply 485 VCC;
a second end of the ninth resistor R62 is connected to the first power source 485 VCC;
a second end of the tenth resistor R64 is grounded.
Further, the present invention provides an alternative embodiment, in which the bidirectional zener diode TVS1 is used to control the voltage to ground of the sixth port a of the 485 chip and the voltage to ground of the seventh port B of the 485 chip within a preset range. The bidirectional voltage stabilizing diode TVS1 can restrict the voltage of the pins A and B to the ground and the voltage between the pins A and B to a preset range, and the preset range can be within 6.5V so as to protect the 485 chip.
Further, in an optional embodiment of the present invention, the circuit further includes a capacitor, and the capacitor is connected to a power supply connected to the eighth pin of the 485 circuit; the other end of the capacitor is grounded. When the circuit board is designed, if no special requirements are made on the 485 chips, a microfarad capacitor, for example, a capacitor of 0.1 microfarad, can be placed beside each 485 chip. When the PCB is wired, the distance between the capacitor and the power supply pin is preferably within a preset range, and the preset range can be within 2 mm. The capacitor designed here is a power supply bypass capacitor, and is used for providing a clean power supply for the 485 chip so as to enable the 485 chip to stably work.
The above-mentioned embodiment of the utility model provides a communication circuit is provided to 485 communication circuit has been introduced as the example the utility model provides a part of circuit constitutes and relation of connection, the embodiment of the utility model provides a circuit compares with the circuit among the prior art that provides, the embodiment of the utility model provides a communication circuit is simple, through triode circuit, carries out the plastic to the optical coupler device output end data waveform, shortens the ascending decline of wave form and follows the time to output stable high-low level square wave. The communication delay of the 485 communication transceiver is reduced, the effective pulse width of the transceiving data is increased, the communication is more stable, and the packet loss is not easy. Compare behind the opto-coupler device output current that flows among the prior art, through last pull-down resistance, then need through whole rising after the decline edge, just can produce the high low level data that can utilize, the utility model discloses an at opto-coupler device output termination triode, utilize the switching characteristic of triode, the threshold value that the triode was opened and is turn-offed is lower promptly, only needs the partly of the optical-coupler output waveform rise decline edge required time among the prior art can satisfy the action requirement, can provide the high low level data of standard after the action, so shortened the time that the waveform rises and descends to data effective pulse width has been strengthened, and then communication stability has been improved.
The embodiment of the utility model provides a still provide an electric energy meter, the electric energy meter includes the arbitrary item that above-mentioned embodiment provided the circuit. The electric energy meter utilizes the circuit in the embodiment to complete data interaction with the external equipment.
The embodiment of the present invention provides "first" and "second" in the names of "first circuit", "second circuit", etc. which are used as name labels, and do not represent the first and second in sequence.
From the above description of the embodiments, it is clear to those skilled in the art that all or part of the steps in the circuits of the above embodiments may be implemented by software plus a general hardware platform. Based on such understanding, the technical solution of the present invention can be embodied in the form of a software product, which can be stored in a storage medium, such as a REad-only memory (ROM)/RAM, a magnetic disk, an optical disk, etc., and includes several instructions for enabling a computer device (which may be a personal computer, a server, or a network communication device such as a router, etc.) to execute the circuits according to the embodiments or some parts of the embodiments of the present invention.
The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. One of ordinary skill in the art can understand and implement it without inventive effort.
The above description is only an exemplary embodiment of the present invention, and is not intended to limit the scope of the present invention.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (11)
1. A communication circuit is characterized by comprising a 485 chip, a first circuit, a second circuit, a third circuit and a first resistor;
the first circuit is connected with a first pin of the 485 chip;
the output end of the second circuit is connected with the second pin and the third pin of the 485 chip;
a third port of the third circuit is connected with a fourth pin of the 485 chip;
the first end of the first resistor is connected with the first port of the second circuit, and the second end of the first resistor is connected with the third port of the third circuit and grounded;
a fourth port of the third circuit is connected with a second port of the second circuit;
the first circuit comprises a first triode, the first triode is turned off when a first pin of the 485 chip outputs a high-level signal, and is turned on when the first pin of the 485 chip outputs a low-level signal;
the second circuit comprises a second triode which is turned off when a data sending port outputs a high level signal and is turned on when the data sending port outputs a low level signal.
2. The circuit of claim 1, wherein the first transistor is an NPN transistor.
3. The circuit of claim 1, wherein the second transistor is a PNP transistor.
4. The circuit of claim 1, wherein the first circuit further comprises a first optocoupler device, a second resistor, a third resistor, a fourth resistor, and a fifth resistor;
a first port of the first optocoupler is connected with a first end of the second resistor; a third port of the first optocoupler is connected with a first end of the fourth resistor and a first end of the fifth resistor; a fourth port of the first optocoupler is connected with a first end of the third resistor;
the base electrode of the first triode is connected with the second end of the fourth resistor; the emitter of the first triode is connected with the second end of the fifth resistor and is grounded; the collector of the first triode is connected with the data receiving port;
the second end of the second resistor is connected with a first power supply;
and the first end of the third resistor is connected with a second power supply, and the second end of the third resistor is connected with the data receiving port.
5. The circuit of claim 1, wherein the second circuit further comprises a sixth resistor and a seventh resistor;
the base electrode of the second triode is connected with the first end of the seventh resistor; an emitting electrode of the second triode is connected with a first end of the sixth resistor; a collector of the second triode is connected with the second pin and the third pin of the 485 chip;
and the second end of the sixth resistor and the second end of the seventh resistor are connected with the fourth port of the third circuit.
6. The circuit of claim 1, wherein the third circuit comprises a second optocoupler device and an eighth resistor;
a first port of the second optocoupler is connected with a first end of the eighth resistor; a second port of the second optocoupler is connected with a data transmission port;
and the second end of the eighth resistor is connected with a second power supply.
7. The circuit of claim 1, further comprising a ninth resistor, a tenth resistor, a bidirectional zener diode;
a fifth port of the 485 chip is grounded; a sixth port of the 485 chip is connected with the first end of the ninth resistor and the first end of the bidirectional voltage stabilizing diode; a seventh port of the 485 chip is connected with the first end of the tenth resistor and the second end of the bidirectional voltage stabilizing diode; an eighth port of the 485 chip is connected with a first power supply;
a second end of the ninth resistor is connected with the first power supply;
a second end of the tenth resistor is grounded.
8. The circuit of claim 7, wherein the zener diode is configured to control a voltage to ground of the sixth port of the 485 chip and a voltage to ground of the seventh port of the 485 chip within a preset range.
9. The circuit of claim 1, further comprising a capacitor connected to a power supply connected to an eighth pin of the 485 circuit; the other end of the capacitor is grounded.
10. The circuit of claim 9, wherein the capacitor is located within a predetermined distance from a power pin to which the capacitor is connected.
11. An electric energy meter, characterized in that it comprises a circuit according to any one of claims 1-10.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202222919050.2U CN218416386U (en) | 2022-10-31 | 2022-10-31 | Communication circuit and electric energy meter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202222919050.2U CN218416386U (en) | 2022-10-31 | 2022-10-31 | Communication circuit and electric energy meter |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN218416386U true CN218416386U (en) | 2023-01-31 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202222919050.2U Active CN218416386U (en) | 2022-10-31 | 2022-10-31 | Communication circuit and electric energy meter |
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| Country | Link |
|---|---|
| CN (1) | CN218416386U (en) |
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- 2022-10-31 CN CN202222919050.2U patent/CN218416386U/en active Active
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