Communication circuit, alarm, gas meter and gas alarm system

Abstract

The application provides a communication circuit, an alarm, a gas meter and a gas alarm system. The communication circuit comprises a master controller, a communication data sending circuit, a communication data receiving circuit and an interface circuit. An alarm signal is transmitted between the master controller and the interface circuit. When data is transmitted between the gas meter and a server, first data to be transmitted is loaded on the alarm signal through the communication data sending circuit, or second data is stripped from the alarm signal loaded with the data through the communication data receiving circuit. The alarm signal loaded with the data is transmitted through the existing interface circuit, thereby improving the utilization rate of the interface circuit and not affecting the state of the alarm signal. The first device transfers the data communication transmission process to the second device through the communication circuit, thereby saving the communication power consumption of the first device. The data transmission timeliness of the first device can also be ensured by adjusting the data transmission frequency of the second device.

Description

Technical Field

[0001] This application relates to the field of communication technology, and in particular to a communication circuit, an alarm, a gas meter, and a gas alarm system. Background Technology

[0002] A gas meter is a device used to calculate gas flow and control gas transmission. To prevent gas leaks, alarms are usually deployed near gas pipelines to monitor the gas concentration around the pipelines. When an abnormal gas concentration is detected, the gas meter will sound an alarm so that it can adjust the gas transmission process.

[0003] The gas meter connects to the server via a communication link, typically a Narrowband Internet of Things (NB-IoT) link. The gas meter interacts with the server via this communication channel about once a day. This results in low data transmission timeliness between the gas meter and the server. Increasing the frequency of interactions between the gas meter and the server would increase the power consumption of the gas meter used for communication, thus increasing the frequency of battery replacements by the user.

[0004] Therefore, improving the timeliness of data transmission while maintaining low power consumption of gas meters has become a key research focus. Summary of the Invention

[0005] This application provides a communication circuit, an alarm, a gas meter, and a gas alarm system to solve the above-mentioned technical problems.

[0006] In a first aspect, this application provides a communication circuit, including: a main controller, a communication data receiving circuit, a communication data transmitting circuit, and an interface circuit;

[0007] The main controller and the interface circuit are electrically connected for transmitting alarm signals; the alarm signal includes a high-level signal or a low-level signal, wherein the high-level signal is greater than a preset threshold and the low-level signal is less than the preset threshold;

[0008] The input terminal of the communication data transmission circuit is electrically connected to the main controller, and its output terminal is electrically connected to the interface circuit, for transmitting the first data sent by the main controller to the interface circuit;

[0009] The interface circuit is used to output an alarm signal that loads the first data, and is also used to receive an alarm signal that loads the second data; wherein, the high-level signal that loads the first data or the second data is greater than the preset threshold, and the low-level signal that loads the first data or the second data is less than the preset threshold;

[0010] The input terminal of the communication data receiving circuit is electrically connected to the interface circuit, and its output terminal is electrically connected to the main controller. It is used to obtain the alarm signal of loading the second data and send the second data to the main controller.

[0011] In the above technical solution, the communication circuit includes a main controller, a communication data transmitting circuit, a communication data receiving circuit, and an interface circuit. The main controller and the interface circuit are electrically connected to transmit alarm signals. The communication data transmitting circuit, located between the main controller and the interface circuit, loads the first data to be transmitted onto the alarm signal. The communication data receiving circuit, located between the main controller and the interface circuit, strips the second data from the alarm signal loaded with the data without affecting the state of the alarm signal. The first device transfers the data communication transmission process to the second device through the communication circuit, which can save the communication power consumption of the first device. By adjusting the data transmission frequency of the second device, the timeliness of data transmission of the first device can also be guaranteed.

[0012] Optionally, the communication data transmission circuit includes a first capacitor, and the second terminal of the first capacitor serves as the output terminal of the communication data transmission circuit.

[0013] The communication data transmission circuit is used to transmit the first data sent by the main controller to the interface circuit, including:

[0014] The communication data transmission circuit is used to obtain the first preset level signal sent by the main controller when the first data is not sent, and to determine that the potential value of the first end of the first capacitor is the reference potential value, and the potential value of the second end of the first capacitor is the potential value corresponding to the alarm signal of no data being loaded.

[0015] The communication data transmission circuit is further configured to, when receiving the electrical signal corresponding to the first data sent by the master controller, adjust the potential value of the second terminal of the first capacitor according to the change in the potential value of the first terminal of the first capacitor, and determine the potential value as the potential value corresponding to the alarm signal loading the first data.

[0016] Optionally, the first capacitor is used to output an alarm signal loaded with low-level data from its second terminal based on the difference between the potential value of its first terminal when the second switching device is turned on and the potential value of its first terminal when the control terminal of the first switching device receives the first preset level signal.

[0017] The first capacitor is also used to output an alarm signal loaded with high-level data from its second terminal by the difference between the potential value of its first terminal when the second switching device is turned off and the potential value of its first terminal when the control terminal of the first switching device receives the first preset level signal.

[0018] In the above technical solution, by setting a first capacitor in the communication data transmission circuit, the first data and the alarm signal are isolated. Through the coupling effect of the first capacitor, the first data is loaded onto the alarm signal without affecting the alarm signal, thus ensuring the security of the first data transmission.

[0019] Optionally, the communication data receiving circuit includes a second capacitor, and the first end of the second capacitor serves as the input terminal of the communication data receiving circuit;

[0020] The communication data receiving circuit is used to output a second preset level signal when receiving an alarm signal that has not been loaded with second data;

[0021] When receiving an alarm signal that loads the second data, the system outputs a level signal corresponding to the second data based on the level change at the first terminal of the second capacitor.

[0022] Optionally, the communication data receiving circuit further includes a voltage difference limiting unit and a comparator;

[0023] The first terminal of the voltage difference limiting unit is electrically connected to the positive input terminal of the comparator and the second terminal of the second capacitor, and its second terminal is electrically connected to the inverting input terminal of the comparator. It is used to output a preset positive electrical signal from its first output terminal and a preset inverted electrical signal from its second output terminal. The preset positive electrical signal is greater than the preset inverted electrical signal.

[0024] The output terminal of the comparator serves as the output terminal of the communication data receiving circuit. During the transmission of the second data by the communication data receiving circuit, when the level value obtained at its positive input terminal is greater than the level value obtained at its negative input terminal, it outputs a high-level signal from the second data; when the level value obtained at its positive input terminal is less than the level value obtained at its negative input terminal, it outputs a low-level signal from the second data.

[0025] Optionally, the level difference between the preset positive electrical signal and the preset negative electrical signal is less than the maximum level difference between the alarm signal with the second data loaded and the alarm signal without the second data loaded;

[0026] The second capacitor is used to control the potential value of the first terminal of the voltage difference limiting unit to be greater than the potential value of the second terminal based on the level difference between the alarm signal with high-level data in the second data and the alarm signal without the second data.

[0027] The second capacitor is also used to obtain the level difference between the alarm signal with low-level data loaded in the second data and the alarm signal without the second data loaded based on the first terminal of the capacitor, and to control the potential value of the first terminal of the voltage difference limiting unit to be less than the potential value of the second terminal.

[0028] In the above technical solution, a second capacitor is set at the input end of the communication data receiving circuit to perform DC blocking operation. The change in the electrical signal received by the second capacitor is amplified by the comparator in the communication data receiving circuit to extract the second data from the electrical signal, thereby ensuring the security of the second data transmission.

[0029] Optionally, the voltage difference limiting unit includes a third bias resistor, a fourth bias resistor, and a threshold holding unit;

[0030] The first end of the third bias resistor is electrically connected to the power supply, and its second end is electrically connected to the first end of the threshold holding unit.

[0031] The first end of the threshold holding unit serves as the first end of the voltage difference limiting unit, and its second end serves as the second end of the voltage difference limiting unit.

[0032] The first end of the fourth bias resistor is electrically connected to the second end of the threshold holding unit, and the second end is grounded.

[0033] Optionally, the threshold holding unit includes an eighth resistor, with a first end of the eighth resistor serving as a first end of the threshold holding unit and a second end of the eighth resistor serving as a second end of the threshold holding unit;

[0034] or,

[0035] The threshold holding unit includes a digital-to-analog converter, a first output terminal of the digital-to-analog converter serving as a first terminal of the threshold holding unit, and a second output terminal of the digital-to-analog converter serving as a second terminal of the threshold holding unit. The digital-to-analog converter is used to adjust the voltage difference between its first terminal and its second terminal according to voltage regulation data received at its input terminal.

[0036] In the above technical solution, the voltage difference limiting unit protects the voltage difference between the positive and negative input terminals of the comparator through a set threshold holding unit, preventing noise fluctuations on the alarm signal from causing the communication data receiving circuit to erroneously output the second data.

[0037] Secondly, this application provides an alarm device including the communication circuit described in any of the claims in the first aspect.

[0038] In the above technical solution, by setting the communication circuit in the alarm, the gas meter uses the alarm as a gateway to send and receive data with the server when communicating with the server. The communication process does not consume the power of the gas meter, reducing the frequency of users replacing the gas meter battery.

[0039] Thirdly, this application provides a gas meter including the communication circuit described in any of the claims in the first aspect.

[0040] In the above technical solution, by setting the communication circuit in the gas meter, the process of the gas meter transmitting data between itself and the server is transferred to an external circuit electrically connected to its interface circuit, thereby reducing the power consumption of the gas meter during the communication process.

[0041] Fourthly, this application provides a gas alarm system, including the alarm described in the second aspect and / or the gas meter described in the third aspect.

[0042] In the above technical solution, by setting up a communication circuit in the alarm and / or gas meter, the gas meter loads the first data to be uploaded onto the alarm signal according to the communication data sending circuit, and transmits it to the alarm through the existing interface circuit. The alarm then parses the alarm signal loaded with the first data according to the communication data receiving circuit and uploads the first data. Furthermore, after downloading second data from the server, the alarm loads the second data onto the alarm signal according to the communication data sending circuit and transmits the alarm signal to the gas meter through the existing interface circuit. The gas meter then parses the alarm signal loaded with the second data according to the communication data receiving circuit to obtain the second data. During the above process, the data transmission does not affect the alarm signal, which not only improves the utilization rate of the interface but also ensures the accuracy and security of data transmission between the two systems.

[0043] This application provides a communication circuit, an alarm, a gas meter, and a gas alarm system. The communication circuit includes a main controller, a communication data transmitting circuit, a communication data receiving circuit, and an interface circuit. The main controller and the interface circuit transmit alarm signals. When transmitting data between the gas meter and the server, the first data to be transmitted can be loaded onto the alarm signal through the communication data transmitting circuit, or the second data can be stripped from the alarm signal loaded with the data through the communication data receiving circuit. The alarm signal loaded with the data is transmitted through the existing interface circuit, which improves the utilization rate of the interface circuit and does not affect the state of the alarm signal. The first device transfers the data communication transmission process to the second device through the communication circuit, which can save the communication power consumption of the first device. By adjusting the data transmission frequency of the second device, the timeliness of data transmission of the first device can also be guaranteed. Attached Figure Description

[0044] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0045] Figure 1This is a schematic diagram of a conventional gas alarm system provided in accordance with an exemplary embodiment of this application;

[0046] Figure 2 This is a schematic diagram of the structure of a gas alarm system provided in an exemplary embodiment of this application;

[0047] Figure 3 This is a schematic diagram of the structure of a gas alarm system provided in another exemplary embodiment of this application;

[0048] Figure 4 This is a schematic diagram of the structure of a gas alarm system provided in another exemplary embodiment of this application;

[0049] Figure 5 This is a circuit structure diagram of a communication circuit provided in accordance with an exemplary embodiment of this application;

[0050] Figure 6 This is a waveform diagram of an alarm signal for loading data provided in an exemplary embodiment of this application;

[0051] Figure 7A and Figure 7B This is a schematic diagram of the structure of a voltage difference limiting unit provided in an exemplary embodiment of this application;

[0052] Figure 8 This is a schematic diagram of the structure of a comparator provided in this application according to an exemplary embodiment.

[0053] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0054] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0055] Figure 1 This is a schematic diagram of a conventional gas alarm system provided according to an exemplary embodiment of this application, such as... Figure 1 As shown, it includes a gas meter 102, an alarm 101, a gas pipeline 103, and a server 104.

[0056] The gas meter 102 is installed on the gas pipeline 103 to control the process of gas pipeline 103 transporting gas.

[0057] Alarm 101 is electrically connected to gas meter 102 and installed near gas pipeline 103. It is used to monitor the gas concentration around gas pipeline 103. When the gas concentration exceeds a preset safety threshold, it generates an alarm signal and sends the alarm information to gas meter 102, so that gas meter 102 can adjust the gas delivery process of gas pipeline 103 according to the alarm information. For example, it can close the valve installed on gas pipeline 103.

[0058] The server 104 is connected to multiple gas meters 102 for obtaining data uploaded by the gas meters 102 (e.g., gas consumption, pipeline temperature, etc.) at preset time intervals, and transmitting control data to the gas meters 102 when controlling the gas meters 102 to perform relevant adjustments.

[0059] Since the gas meter 102 is battery-powered, in order to reduce the frequency of users replacing the gas meter battery, the gas meter 102 typically communicates with the server 104 once a day, resulting in low timeliness of data transmission between the gas meter 102 and the server 104. Increasing the frequency of communication between the gas meter 102 and the server 104 would increase the power consumption of the gas meter 102 used for communication, and increase the frequency of users replacing the gas meter battery.

[0060] Therefore, improving the timeliness of data transmission while maintaining low power consumption of gas meters has become a key research focus.

[0061] This application provides a communication circuit, an alarm, a gas meter, and a gas alarm system, aiming to solve the technical problem of the incompatibility between low-power operation of gas meters and timely data transmission. The technical concept of this application is to add a data transmission circuit to the alarm and gas meter, simultaneously transmitting alarm signals and data through the existing alarm signal transmission interface. Furthermore, a controller not installed in the gas meter is used to communicate and transmit data related to the gas meter with a server, avoiding the power consumption of the gas meter used for communication transmission while ensuring timely data transmission.

[0062] The following is an explanation of the structural diagrams of various gas alarm systems provided in this application.

[0063] Figure 2 This is a schematic diagram of the structure of a gas alarm system provided according to an exemplary embodiment of this application, as shown below. Figure 2 As shown, it includes a gas meter 102, an alarm 101, and a server 104. The gas meter 102 and the alarm 101 are electrically connected, and the alarm 101 and the server 104 are communicatively connected.

[0064] The alarm 101 includes a first communication circuit 1011, which includes a main controller 1012, a communication data receiving circuit 1013, a communication data sending circuit 1014, and an interface circuit 1015.

[0065] The main controller 1012 and the interface circuit 1015 are electrically connected and are used to generate and send an alarm signal to the interface circuit 1015 when an abnormal gas condition is detected.

[0066] Alarm signals include high-level signals or low-level signals. High-level signals are greater than a preset threshold, and low-level signals are less than a preset threshold.

[0067] In some embodiments, a high-level alarm signal indicates that the gas concentration is normal and no alarm is triggered; a low-level alarm signal indicates that the gas concentration is abnormal and an alarm is triggered.

[0068] The input terminal of the communication data transmission circuit 1014 is electrically connected to the main controller 1012, and its output terminal is electrically connected to the interface circuit 1015, for transmitting the first data sent by the main controller 1012 to the interface circuit 1015. This first data is the data downloaded by the alarm 101 from the server 104.

[0069] The interface circuit 1015 is used to output an alarm signal loaded with the first data, so that the gas meter 102 can parse the first data loaded with the alarm signal and perform corresponding data processing on the first data.

[0070] Interface circuit 1015 is also used to receive an alarm signal generated by gas meter 102, which loads second data. The second data is the data that gas meter 102 needs to upload to server 104.

[0071] Wherein, the high-level signal for loading the first data or the second data is greater than a preset threshold, and the low-level signal for loading the first data or the second data is less than a preset threshold.

[0072] In other words, loading the first or second data alarm signal does not change the alarm status of the alarm signal.

[0073] The interface circuit 1015 can use the interface circuit 1015 in the original alarm 101, without the need to adjust the circuit structure of the interface circuit 1015.

[0074] The input terminal of the communication data receiving circuit 1013 is electrically connected to the interface circuit 1015, and its output terminal is electrically connected to the main controller 1012. It is used to obtain the alarm signal loaded with the second data and send the second data to the main controller 1012.

[0075] Since the main controller 1012 is not located inside the gas meter 102, when communicating with the server 104 to transmit the first and second data, it will not increase the power consumption of the gas meter 102, and the data can be transmitted in a timely manner.

[0076] In the above description, the terms "first" and "second" are used only to distinguish data and do not have any specific meaning.

[0077] Figure 3 This is a schematic diagram of the structure of a gas alarm system provided in another exemplary embodiment of this application, such as... Figure 3 As shown, the system includes an alarm 101, a gas meter 102, and a server 104. The gas meter 102 and the alarm 101 are electrically connected, and the alarm 101 and the server 104 are communicatively connected.

[0078] The gas meter 102 includes a second communication circuit 1021, which includes a main controller 1022, a communication data receiving circuit 1023, a communication data sending circuit 1024, and an interface circuit 1025.

[0079] Alarm 101 is used to download first data from server 104, load the first data onto an alarm signal, and transmit it to interface circuit 1025. The loading of the first data onto the alarm signal does not affect the level of the alarm signal.

[0080] The interface circuit 1025 is electrically connected to the main controller 1022 and is used to acquire the alarm signal transmitted by the alarm device 101 and transmit it to the main controller 1022.

[0081] The interface circuit 1025 and the communication data receiving circuit 1023 are electrically connected and are used to strip the first data from the alarm signal of the loading data and transmit it to the main controller 1022 so that the main controller 1022 can store the first data or adjust the configuration information based on the first data.

[0082] The main controller 1022 is used to transmit the second data to be uploaded to the server 104 to the interface circuit 1025 through the communication data transmission circuit 1024, so as to load the second data onto the alarm signal.

[0083] The interface circuit 1025 transmits the alarm signal loaded with the second data to the alarm 101, so that the alarm 101 can separate the second data from the alarm signal and upload it to the server 104.

[0084] Since the main controller 1022 no longer communicates and transmits data directly with the server 104, but instead transfers the data transmission process to the alarm, the power consumption of the gas meter is reduced. While ensuring the data transmission rate of the alarm, the timeliness of data interaction between the gas meter and the server can be guaranteed.

[0085] Figure 4 This is a schematic diagram of the structure of a gas alarm system provided in this application according to another exemplary embodiment. Figure 4 The circuit structure includes both Figure 2 The first communication circuit 1011 shown also includes Figure 3 The second communication circuit 1021 shown.

[0086] The interface circuit 1025 is electrically connected to the interface circuit 1015 in the alarm 101, and is used to receive the alarm signal loaded with the first data generated by the communication data transmission circuit 1014 in the alarm 101.

[0087] The input terminal of the communication data receiving circuit 1023 is electrically connected to the interface circuit 1025, and the output terminal is electrically connected to the main controller 1022. It is used to obtain the alarm signal loaded with the first data, strip the first data from the alarm signal, and send the first data to the main controller 1022.

[0088] The main controller 1022 is used to obtain first data, store the first data, or adjust the configuration information of the gas meter 102 according to the first data. For example, it can adjust the valve opening on the gas pipeline according to the first data.

[0089] The main controller 1022 is also used to collect statistics on the amount of gas passing through the gas pipeline and the pipeline temperature. This information needs to be uploaded to the server 104.

[0090] The input terminals of the main controller 1022 and the communication data transmission circuit 1024 are electrically connected, and the output terminal of the communication data transmission circuit 1024 is electrically connected to the interface circuit 1025. The communication data transmission circuit 1024 is used to load the data sent by the main controller 1022 onto the alarm signal and synchronize the alarm signal with the loaded data to the interface circuit 1015.

[0091] The communication data receiving circuit 1013 obtains the change in the alarm signal from the interface circuit 1015, determines the data to be uploaded by the main controller 1022 from the change, and transmits the data to the main controller 1012.

[0092] The main controller 1012 uploads the acquired data to the server 104.

[0093] In the above technical solution, by setting up a communication circuit in both the alarm and the gas meter, the gas meter loads the first data to be uploaded onto the alarm signal according to the communication data sending circuit, and transmits it to the alarm through the existing interface circuit. The alarm then parses the alarm signal loaded with the first data according to the communication data receiving circuit and uploads the first data. Furthermore, after downloading second data from the server, the alarm loads the second data onto the alarm signal according to the communication data sending circuit and transmits the alarm signal to the gas meter through the existing interface circuit. The gas meter then parses the alarm signal loaded with the second data according to the communication data receiving circuit to obtain the second data. During the above process, the data transmission does not affect the alarm signal, which not only improves the utilization rate of the interface but also ensures the accuracy and security of data transmission between them.

[0094] The following is a detailed explanation of the circuit structure of each circuit in the communication circuit of the alarm and / or gas meter.

[0095] Figure 5 This is a circuit structure diagram of a communication circuit provided in accordance with an exemplary embodiment of this application.

[0096] exist Figure 5 In the communication data transmission circuit 1014, a first capacitor C1 is included, and the second end of the first capacitor C1 serves as the output terminal of the communication data transmission circuit 1014.

[0097] The communication data transmission circuit 1014 is used to obtain the first preset level signal sent by the master controller 1012 when the first data is not transmitted, and to determine that the potential value of the first end of the first capacitor C1 is the reference potential value, and the potential value of the second end of the first capacitor C1 is the potential value corresponding to the alarm signal of no data being loaded.

[0098] The communication data transmission circuit 1014 is also used to adjust the potential value of the second terminal of the first capacitor C1 according to the change in the potential value of the first terminal of the first capacitor C1 when receiving the electrical signal corresponding to the first data sent by the master controller 1012, and determine the potential value as the potential value corresponding to the alarm signal that loads the first data.

[0099] In one embodiment, the first data includes high-level data and low-level data, where the high-level data represents a digital signal "1" and the low-level data represents a digital signal "0".

[0100] The communication data transmission circuit 1014 also includes a first switching device Q1, a second switching device Q2, a pull-up resistor R1, a first bias resistor R2, and a second bias resistor R3.

[0101] The control terminal of the first switching device Q1 is coupled to the data transmission terminal of the main controller 1012. Its first terminal is electrically connected to the second terminal of the pull-up resistor R1 and the control terminal of the second switching device Q2, and its second terminal is grounded.

[0102] In some embodiments, the communication data transmission circuit 1014 further includes a first current-limiting resistor R4, the first end of which is electrically connected to the data transmission end of the main controller 1012, and the second end of which is electrically connected to the control end of the first switching device Q1, for preventing the first switching device Q1 from being broken down when the control end of the first switching device Q1 is connected to the second end or to the first end.

[0103] The first switching device Q1 and the second switching device Q2 are transistors.

[0104] When the first switching device Q1 and the second switching device Q2 are NPN transistors, the first switching device Q1 is turned on when it receives high-level data in the first data and turned off when it receives low-level data in the first data.

[0105] When the first switching device Q1 is turned on, its first terminal is grounded and the level of the first terminal is low. When the first switching device Q1 is turned off, its first terminal and second terminal are disconnected. Since its first terminal is coupled to the power supply VDD, the level of the first terminal is high.

[0106] The first end of the pull-up resistor R1 is electrically connected to the power supply VDD and is used to limit current when the first switching device Q1 is turned on.

[0107] The first terminal of the second switching device Q2 is electrically connected to the second terminal of the first bias resistor R2, the first terminal of the first capacitor C1, and the first terminal of the second bias resistor R3. Its second terminal is grounded and is used to turn off when the first switching device Q1 is turned on and turn on when the first switching device Q1 is turned off.

[0108] The first terminal of the first bias resistor R2 is electrically connected to the power supply VDD, and the second terminal of the second bias resistor R3 is grounded.

[0109] When the second switching device Q2 is turned on, its first terminal is grounded and the potential value of the first terminal is 0V. The potential of the first terminal of the first capacitor C1, which is electrically connected to the first terminal of the second switching device Q2, is adjusted to 0.

[0110] When the second switching device Q2 is turned off, its first and second terminals are disconnected. The potential value of its first terminal is determined based on the first bias resistor R2, the second bias resistor R3, and the power supply VDD. The potential value is the voltage divider value.

[0111] When the first terminal of the first capacitor C1 does not receive the first data, and the electrical signal it receives is the first preset level signal obtained by the control terminal of the first switching device Q1, the potential value of the first terminal of the second switching device Q2 is determined as the reference potential value.

[0112] The first capacitor C1 outputs an alarm signal from its second terminal, which loads low-level data from the first data, based on the difference between the potential value at its first terminal and the reference potential value when the second switching device Q2 is turned on.

[0113] When the second switching device Q2 is turned off, the difference between the potential value at its first terminal and the reference potential value is used to output an alarm signal from its second terminal, which loads the high-level data in the first data.

[0114] In one embodiment, the first preset level signal is a high level signal, the second switching device Q2 is turned off, and the potential value of the first terminal of the first capacitor C1 is the voltage divider value; then when the main controller 1012 transmits high level data in the first data, the second switching device Q2 remains in the off state, the potential value of the first terminal of the first capacitor C1 remains unchanged, and the potential value of its second terminal also remains unchanged.

[0115] Based on this, regardless of whether the alarm signal transmitted between the main controller 1012 and the interface circuit 1015 is in a high-level non-alarm state or a low-level alarm state, the high-level signal of the first data output by the main controller 1012 will not change the potential value of the second end of the first capacitor C1.

[0116] When the main controller 1012 transmits low-level data in the first data, the second switching device Q2 is turned on, and the potential value of the first terminal of the first capacitor C1 drops from the voltage divider value to 0V. According to the coupling effect of the first capacitor C1, the potential value of the second terminal of the first capacitor C1 will also decrease.

[0117] If the voltage difference at the second terminal of the first capacitor C1 is much smaller than the voltage value when the alarm signal is at a high level, then when the alarm signal is at a high level, it will remain at a high level after the voltage difference is reduced, and the alarm signal will remain in a non-alarm state. When the alarm signal is at a low level, the voltage value will be even lower after the voltage difference is reduced, and the alarm signal will remain in an alarm state.

[0118] In another embodiment, the first preset level signal is a low level signal, the second switching device Q2 is turned on, the reference potential value of the first terminal of the first capacitor C1 is 0V, and the potential value of the second terminal is the potential value of the alarm signal for no loaded data. When the main controller 1012 outputs a low level signal of the first data, the second switching device Q2 remains on, the potential value of the first terminal of the first capacitor C1 remains unchanged, and therefore the potential value of its second terminal also remains unchanged.

[0119] Regardless of whether the alarm signal transmitted between the main controller 1012 and the interface circuit 1015 is in a high-level non-alarm state or a low-level alarm state, the low-level signal of the first data output by the main controller 1012 will not change the potential value of the second end of the first capacitor C1.

[0120] When the main controller 1012 transmits high-level data in the first data, the second switching device Q2 is turned off, and the potential value of the first terminal of the first capacitor C1 rises from 0V to the voltage divider value. According to the coupling effect of the first capacitor C1, the potential value of the second terminal of the first capacitor C1 will rise.

[0121] When the alarm signal is a high-level signal, it remains a high-level signal after rising, and the alarm signal remains in the alarm state. When the alarm signal is a low-level signal, if the difference between the low-level signal and the preset threshold is much greater than the voltage difference at the second end of the first capacitor C1, then after the alarm signal rises to the above voltage difference, the alarm signal remains a low-level signal, and the alarm signal remains in the non-alarm state.

[0122] The preset threshold is a voltage value that defines the level state of the alarm signal. When the voltage value is greater than the preset threshold, the alarm signal is a high-level signal; when the voltage value is less than the preset threshold, the alarm signal is a low-level signal.

[0123] In one embodiment, the waveform diagrams of the alarm signal with loaded data and the alarm signal without loaded data are as follows: Figure 6 As shown, the first preset level signal obtained by the communication data transmission circuit 1014 is a high-level signal, the high-level signal in the alarm signal is transmitted during time period t1, and the low-level signal in the alarm signal is transmitted during time period t2.

[0124] When transmitting data, a set of data includes a wavefront, valid data, and a wave tail. The wavefront is the identifier that the data transmission begins, the valid data is the actual data transmitted in the set of data, and the wave tail is the identifier that the data transmission ends.

[0125] During time period t1, if the valid data transmitted is "1101", then the alarm signal will only decrease in potential at the position corresponding to digital signal 0, and the alarm signal after the potential decreases will still be at a high level.

[0126] During time period t2, the valid data transmitted is "1001". Similar to time period t1, this data does not affect the status of the alarm signal.

[0127] The interface circuit 1013 includes a terminal P1 and a fifth resistor R5. The first end of the fifth resistor R5 is electrically connected to the power supply VDD, the second end is electrically connected to the first pin of the terminal P1, and the second pin of the terminal P1 is grounded.

[0128] The first pin of terminal P1 is electrically connected to the second end of the first capacitor C1 and the alarm signal output terminal of the main controller 1012. This is used to obtain an alarm signal from the alarm signal output terminal. When the communication data transmission circuit 1014 transmits the first data, the first data is adjusted and determined according to the potential value change of the first end of the first capacitor C1, and the first data is loaded onto the alarm signal and then transmitted to the gas meter 102.

[0129] Terminal P1 is also used to adjust the potential value of the alarm signal transmitted by its first pin when the second data transmitted from the gas meter 102 side is obtained. At this time, the signal transmitted by the first pin is the alarm signal that loads the second data.

[0130] The communication data receiving circuit 1013, which is electrically connected to the first pin of terminal P1, includes a second capacitor C2. The first end of the second capacitor C2 serves as the input terminal of the communication data receiving circuit 1013 and is electrically connected to the first pin of terminal P1.

[0131] The output terminal of the communication data receiving circuit 1013 is electrically connected to the data receiving terminal of the main controller 1012. When receiving an alarm signal that has not been loaded with the second data, it outputs a second preset level signal to the data receiving terminal; when receiving an alarm signal that has been loaded with the second data, it outputs a level signal corresponding to the second data according to the level change of the first terminal of the second capacitor.

[0132] The communication data receiving circuit 1013 also includes a voltage difference limiting unit and a comparator U1.

[0133] The first terminal of the voltage difference limiting unit is electrically connected to the positive input terminal of comparator U1 and the second terminal of the second capacitor C2, and its second terminal is electrically connected to the inverting input terminal of comparator U1. It is used to output a preset positive electrical signal CA+ from its first output terminal and a preset inverted electrical signal CA- from its second output terminal. The preset positive electrical signal CA+ is greater than the preset inverted electrical signal CA-, and the voltage difference between the preset positive electrical signal CA+ and the preset inverted electrical signal CA- is a preset noise reduction voltage difference.

[0134] The output of comparator U1 serves as the output of the communication data receiving circuit 1013. During the transmission of the second data by the communication data receiving circuit 1013, when the level value obtained at its positive input terminal is greater than the level value obtained at its inverting input terminal, it outputs a high-level signal from the second data; when the level value obtained at its positive input terminal is less than the level value obtained at its inverting input terminal, it outputs a low-level signal from the second data.

[0135] Based on the above circuit structure, the potential value of the inverting input terminal of comparator U1 will not change, while the potential value of the non-inverting input terminal will be adjusted accordingly based on the change in the potential value of the first terminal of the second capacitor C2, thereby adjusting the preset positive electrical signal CA+ generated by the voltage difference limiting unit.

[0136] If the level difference between the preset positive electrical signal CA+ and the preset reverse electrical signal CA- is less than the maximum value of the level difference between the alarm signal with second data loaded and the alarm signal without second data loaded, then the second capacitor C2 is used to control the potential value of the first terminal of the voltage difference limiting unit to be greater than the potential value of the second terminal based on the level difference between the alarm signal with high-level data in the second data loaded and the alarm signal without second data loaded obtained from its first terminal. Then the comparator U1 outputs a high-level signal as the high-level data in the second data.

[0137] The second capacitor C2 is also used to obtain the level difference between the alarm signal with low-level data in the second data and the alarm signal without the second data based on the first terminal of the voltage difference limiting unit. If the potential value of the first terminal of the control voltage difference limiting unit is less than the potential value of the second terminal, then the comparator U1 outputs a low-level signal as the low-level data in the second data.

[0138] In one embodiment, when the first terminal of the second capacitor C2 receives an alarm signal indicating that no data has been loaded, the potential value of its second terminal is an initial level. If the potential value of this initial level is greater than the potential value of the inverting input terminal of the comparator U1, then the comparator U1 outputs a high-level signal.

[0139] When the alarm signal of high-level data in the second data is received at the first terminal of the second capacitor C2, the potential value of the second terminal of the second capacitor C2 will change with the change of the potential value of its first terminal, and the trend of change is the same. That is, when the level value of the alarm signal with high-level data is increased relative to the alarm signal without data, the potential value of the second terminal of the second capacitor C2 will also increase. Since the electrical signal output from the first terminal of the voltage difference limiting unit is greater than the electrical signal output from the second terminal, the alarm signal of high-level data in the second data makes the first terminal of the comparator U1 still greater than the second terminal, and outputs a high-level signal as the high-level data in the second data.

[0140] When the alarm signal of low-level data in the second data is received at the first terminal of the second capacitor C2, the potential value of the second terminal of the second capacitor C2 will change with the change of the potential value of its first terminal, and the trend of change is the same. That is, the level value of the alarm signal with low-level data is lower than that of the alarm signal without data, and the potential value of the second terminal of the second capacitor C2 will also decrease. Since the voltage difference generated at the second terminal of the second capacitor C2 when the alarm signal with low-level data and the alarm signal without data are limited to be greater than the difference between the preset positive electrical signal and the preset reverse electrical signal generated by the voltage difference limiting unit, the potential value of the positive input terminal of the comparator U1 is less than the potential value of the inverting input terminal when the low-level data in the second data is received. The comparator U1 outputs a low-level signal as the low-level data in the second data.

[0141] The circuit structure of the voltage difference limiting unit is explained below.

[0142] The voltage difference limiting unit includes a third bias resistor R7, a fourth bias resistor R9, and a threshold holding unit 1016.

[0143] The first end of the third bias resistor R7 is electrically connected to the power supply VDD, and its second end is electrically connected to the first end of the threshold holding unit 1016.

[0144] The first end of the threshold holding unit 1016 serves as the first end of the voltage difference limiting unit, and its second end serves as the second end of the voltage difference limiting unit.

[0145] The first terminal of the fourth bias resistor R9 is electrically connected to the second terminal of the threshold holding unit 1016, and the second terminal is grounded.

[0146] In one embodiment, the circuit structure of the threshold holding unit 1016 is as follows: Figure 7A As shown, it includes an eighth resistor R8, the first end of the eighth resistor R8 serves as the first end of the threshold holding unit 1016, and the second end of the eighth resistor R8 serves as the second end of the threshold holding unit 1016.

[0147] Based on the circuit structure table above, the potential value of the preset positive electrical signal output by the voltage difference limiting unit is, and the potential value of the preset reverse electrical signal output by the unit is.

[0148] In another embodiment, the circuit structure of the threshold holding unit 1016 is as follows: Figure 7B As shown, the device includes a digital-to-analog converter (DAC). The first output terminal of the DAC serves as the first terminal of a threshold holding unit 1016, and the second output terminal of the DAC serves as the second terminal of the threshold holding unit 1016. The DAC is used to adjust the voltage difference between its first and second terminals based on the voltage regulation data (Data) received at its input terminal. In other words, it converts the digital signal obtained from its input terminal into an analog voltage difference between its two output terminals. At this time, the third bias resistor R7 and the fourth bias resistor R9 act as current-limiting resistors for the output terminals of the DAC.

[0149] In some embodiments, comparator U1 can be implemented using an integrated chip, while in other embodiments, comparator U1 can be built using discrete components.

[0150] Figure 8 This is a schematic diagram of a comparator built based on discrete components according to an exemplary embodiment of this application, as shown below. Figure 8 As shown, it includes:

[0151] The sixteenth resistor R16 has its first terminal electrically connected to the power supply VDD.

[0152] The seventeenth resistor R17 has its first terminal electrically connected to the second terminal of the sixteenth resistor R16, and its second terminal is grounded.

[0153] The seventh switching device Q7 is electrically connected to the second terminal of the sixteenth resistor R16 and remains in the conducting state according to the voltage value at the second terminal of the sixteenth resistor R6.

[0154] The twenty-first resistor R21 has its first terminal electrically connected to the second terminal of the seventh switching device Q7, and its second terminal is grounded.

[0155] The second terminal of the twelfth resistor R12 is electrically connected to the first terminal of the seventh switching device Q7.

[0156] The thirteenth resistor R13 is electrically connected at its second terminal to the first terminal of the seventh switching device Q7.

[0157] The second terminal of the third switching device Q3 is electrically connected to the first terminal of the twelfth resistor R12 and the first terminal of the thirteenth resistor R13.

[0158] The fourteenth resistor R14 has its first terminal electrically connected to the control terminal of the third switching device Q3, and its second terminal serves as the positive input terminal of comparator U1.

[0159] The tenth resistor R10 has its first terminal electrically connected to the power supply VDD, and its second terminal electrically connected to the first terminal of the third switching device Q3.

[0160] The second terminal of the fourth switching device Q4 is electrically connected to the second terminal of the third switching device Q3.

[0161] The fifteenth resistor R15 has its first end electrically connected to the control terminal of the fourth switching device Q4, and its second end serves as the inverting input terminal of comparator U1.

[0162] The eleventh resistor R11 has its first terminal electrically connected to the power supply VDD, and its second terminal electrically connected to the first terminal of the fourth switching device Q4.

[0163] The fifth switching device Q5 has its first terminal electrically connected to the power supply VDD, and its control terminal electrically connected to the first terminal of the fourth switching device Q4.

[0164] The eighteenth resistor R18 is electrically connected at its first terminal to the second terminal of the fifth switching device Q5.

[0165] The nineteenth resistor R19 has its first terminal electrically connected to the second terminal of the eighteenth resistor R18, and its second terminal is grounded.

[0166] The sixth switching device Q6 has its first terminal electrically connected to the power supply VDD, and its control terminal electrically connected to the second terminal of the eighteenth resistor R18. The second terminal serves as the output terminal of comparator U1.

[0167] The twentieth resistor R20 has its first terminal electrically connected to the second terminal of the sixth switching device Q6, and its second terminal is grounded.

[0168] The comparator built based on the aforementioned discrete components has a more flexible structure, which can reduce the maintenance cost of subsequent circuits.

[0169] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the following claims.

[0170] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A communication circuit, characterized in that, include: Main controller, communication data receiving circuit, communication data transmitting circuit, interface circuit; The main controller and the interface circuit are electrically connected for transmitting alarm signals; the alarm signal includes a high-level signal or a low-level signal, wherein the high-level signal is greater than a preset threshold and the low-level signal is less than the preset threshold; The input terminal of the communication data transmission circuit is electrically connected to the main controller, and its output terminal is electrically connected to the interface circuit, for transmitting the first data sent by the main controller to the interface circuit; The interface circuit is used to output an alarm signal that loads the first data, and is also used to receive an alarm signal that loads the second data; wherein, the high-level signal that loads the first data or the second data is greater than the preset threshold, and the low-level signal that loads the first data or the second data is less than the preset threshold; The input terminal of the communication data receiving circuit is electrically connected to the interface circuit, and its output terminal is electrically connected to the main controller, for obtaining the alarm signal loaded with the second data and sending the second data to the main controller; The communication data transmission circuit includes a first capacitor, and the second end of the first capacitor serves as the output terminal of the communication data transmission circuit. The communication data transmission circuit is used to transmit the first data sent by the main controller to the interface circuit, including: The communication data transmission circuit is used to obtain the first preset level signal sent by the main controller when the first data is not sent, and to determine that the potential value of the first end of the first capacitor is the reference potential value, and the potential value of the second end of the first capacitor is the potential value corresponding to the alarm signal of no data being loaded. The communication data transmission circuit is also used to adjust the potential value of the second terminal of the first capacitor according to the potential value change of the first terminal of the first capacitor when receiving the electrical signal corresponding to the first data sent by the main controller, and to determine the potential value as the potential value corresponding to the alarm signal loading the first data. The communication data receiving circuit includes a second capacitor, and the first end of the second capacitor serves as the input terminal of the communication data receiving circuit. The communication data receiving circuit is used to output a second preset level signal when receiving an alarm signal that has not been loaded with second data; When receiving an alarm signal that loads the second data, the system outputs a level signal corresponding to the second data based on the level change at the first terminal of the second capacitor.

2. The communication circuit according to claim 1, characterized in that, The communication data transmission circuit further includes a first switching device, a second switching device, a pull-up resistor, a first bias resistor, and a second bias resistor; The control terminal of the first switching device is electrically connected to the data transmission terminal of the main controller. Its first terminal is electrically connected to the second terminal of the pull-up resistor and the control terminal of the second switching device. Its second terminal is grounded. It is used to turn on when high-level data in the first data is obtained and turn off when low-level data in the first data is obtained. The first terminal of the pull-up resistor is electrically connected to the power supply. The first terminal of the second switching device is electrically connected to the second terminal of the first bias resistor, the first terminal of the first capacitor, and the first terminal of the second bias resistor. Its second terminal is grounded, and it is used to turn off when the first switching device is turned on and turn on when the first switching device is turned off. The first end of the first bias resistor is electrically connected to the power supply, and the second end of the second bias resistor is grounded.

3. The communication circuit according to claim 2, characterized in that, The first capacitor is used to output an alarm signal loaded with low-level data from its second terminal based on the difference between the potential value of its first terminal when the second switching device is turned on and the potential value of its first terminal when the control terminal of the first switching device receives the first preset level signal. The first capacitor is also used to output an alarm signal loaded with high-level data from its second terminal by the difference between the potential value of its first terminal when the second switching device is turned off and the potential value of its first terminal when the control terminal of the first switching device receives the first preset level signal.

4. The communication circuit according to claim 1, characterized in that, The communication data receiving circuit also includes a voltage difference limiting unit and a comparator; The first terminal of the voltage difference limiting unit is electrically connected to the positive input terminal of the comparator and the second terminal of the second capacitor, and its second terminal is electrically connected to the inverting input terminal of the comparator. It is used to output a preset positive electrical signal from its first output terminal and a preset inverted electrical signal from its second output terminal. The preset positive electrical signal is greater than the preset inverted electrical signal. The output terminal of the comparator serves as the output terminal of the communication data receiving circuit. During the transmission of the second data by the communication data receiving circuit, when the level value obtained at its positive input terminal is greater than the level value obtained at its negative input terminal, it outputs a high-level signal from the second data. When the level value obtained at its positive input terminal is less than the level value obtained at its negative input terminal, the low-level signal in the second data is output.

5. The communication circuit according to claim 4, characterized in that, The level difference between the preset positive electrical signal and the preset negative electrical signal is less than the maximum level difference between the alarm signal with the second data loaded and the alarm signal without the second data loaded. The second capacitor is used to control the potential value of the first terminal of the voltage difference limiting unit to be greater than the potential value of the second terminal based on the level difference between the alarm signal with high-level data in the second data and the alarm signal without the second data. The second capacitor is also used to obtain the level difference between the alarm signal with low-level data loaded in the second data and the alarm signal without the second data loaded based on the first terminal of the capacitor, and to control the potential value of the first terminal of the voltage difference limiting unit to be less than the potential value of the second terminal.

6. The communication circuit according to claim 4, characterized in that, The voltage difference limiting unit includes a third bias resistor, a fourth bias resistor, and a threshold holding unit; The first end of the third bias resistor is electrically connected to the power supply, and its second end is electrically connected to the first end of the threshold holding unit. The first end of the threshold holding unit serves as the first end of the voltage difference limiting unit, and its second end serves as the second end of the voltage difference limiting unit. The first end of the fourth bias resistor is electrically connected to the second end of the threshold holding unit, and the second end is grounded.

7. The communication circuit according to claim 6, characterized in that, The threshold holding unit includes an eighth resistor, the first end of which serves as the first end of the threshold holding unit, and the second end of which serves as the second end of the threshold holding unit. or, The threshold holding unit includes a digital-to-analog converter, a first output terminal of the digital-to-analog converter serving as a first terminal of the threshold holding unit, and a second output terminal of the digital-to-analog converter serving as a second terminal of the threshold holding unit. The digital-to-analog converter is used to adjust the voltage difference between its first terminal and its second terminal according to voltage regulation data received at its input terminal.

8. An alarm device, characterized in that, Includes the communication circuit as described in any one of claims 1 to 7.

9. A gas meter, characterized in that, Includes the communication circuit as described in any one of claims 1 to 7.

10. A gas alarm system, characterized in that, This includes the alarm as described in claim 8 and / or the gas meter as described in claim 9.

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