Reed switch terminal low-energy-consumption sampling circuit for intelligent water meter
By using reed tubes S1 and S2 in the smart water meter, combined with the pull-up and pull-down resistors and filter capacitors of the microcontroller HC32L136, the state of the reed tube is judged only when the base meter is stopped, solving the problem of increasing power consumption in the existing technology and achieving low energy consumption and high-efficiency sampling.
Patent Information
- Application Number
- CN202422570738.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-24
- Publication Date
- 2025-07-25
- Estimated Expiration
- 2034-10-24
AI Technical Summary
The reed circuit sampling circuit of existing smart water meters has increased power consumption when improving sampling accuracy.
Reed tubes S1 and S2 are used, combined with microcontroller HC32L136, and internal pull-up and pull-down resistors and filter capacitors are used to sample and count through external trigger interrupts. Only the reed tube state is judged when the base table is stopped, reducing the judgment frequency to reduce power consumption.
It realizes significantly reducing circuit power consumption, reducing peripheral components and improving response speed without affecting sampling accuracy.
Smart Images
Figure CN223155393U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a reed switch terminal low - energy - consumption sampling circuit for an intelligent water meter, belonging to the technical field of intelligent water meters. Background Art
[0002] In an intelligent water meter, a reed switch circuit is used as a sampling circuit. Most of the existing sampling circuits use a single - chip microcomputer to periodically judge the state of the I / O port for sampling and reading. If the sampling accuracy is to be improved, it is necessary to correspondingly reduce the sampling judgment interval, increase the number of sampling judgments, and increase power consumption. Content of the Utility Model
[0003] The purpose of the utility model is to provide a reed switch terminal low - energy - consumption sampling circuit for an intelligent water meter.
[0004] In order to achieve the above - mentioned purpose, the technical scheme adopted by the utility model is as follows:
[0005] A reed switch terminal low - energy - consumption sampling circuit for an intelligent water meter includes a reed switch S1 and a reed switch S2; one end of the reed switch S1 is connected to GND, the other end is connected to the single - chip microcomputer sampling port CAI1, and is connected to GND through a filter capacitor C1; one end of the reed switch S2 is connected to GND, the other end is connected to the single - chip microcomputer sampling port CAI2, and is connected to GND through a filter capacitor C1; the single - chip microcomputer is HC32L136.
[0006] A further improvement of the technical scheme of the utility model is that the internal pull - up resistor of the single - chip microcomputer HC32L136 is 80 kΩ, and the pull - down resistor is 40 kΩ.
[0007] A further improvement of the technical scheme of the utility model is that both the capacitor C1 and the capacitor C2 are 68 pF.
[0008] Due to adopting the above - mentioned technical scheme, the technical effects obtained by the utility model are as follows:
[0009] For the sampling circuit of this technical scheme, by using the single - chip microcomputer, it does not make judgments under normal working conditions, and uses an external trigger to interrupt the single - chip microcomputer for sampling counting. Only when the basic meter stops and is exactly in the state where a single reed switch is closed, a judgment is made at a certain interval, further reducing power consumption.
[0010] The sampling circuit of the utility model uses the internal pull - up and pull - down switching of the single - chip microcomputer to conduct sampling monitoring and reduce the power consumption of the circuit, reduce the components of the peripheral circuit, and improve the response speed and accuracy. Description of the Drawings
[0011] Figure 1 It is a circuit schematic diagram of the utility model;
[0012] Figure 2 It is a schematic diagram of the circuit working process of the present utility model. Specific embodiments
[0013] In order to make the technical means, creative features, achieved purposes and effects realized by the present utility model easy to understand, the present utility model will be further described below in conjunction with specific embodiments.
[0014] The reed switch terminal low-power sampling circuit for the intelligent water meter includes reed switches S1 and S2; wherein, one end of reed switch S1 is connected to GND, the other end is connected to the single-chip microcomputer sampling port CAI1, and is connected to GND through a filter capacitor C1. Among them, one end of reed switch S2 is connected to GND, the other end is connected to the single-chip microcomputer sampling port CAI2, and is connected to GND through a filter capacitor C1; the single-chip microcomputer is HC32L136.
[0015] In a specific implementation, further, the internal pull-up resistor of the single-chip microcomputer HC32L136 is 80 kΩ, and the pull-down resistor is 40 kΩ.
[0016] As Figure 1 shown, one ends of reed switches S1 and S2 are connected to GND, and the other ends are respectively connected to the single-chip microcomputer sampling ports CAI1 and CAI2, and are connected to GND through filter capacitors C1 and C2. The single-chip microcomputer is HC32L136 (has a sleep state, and the interruption sampling is not affected during sleep, which reduces the power consumption to the greatest extent), the internal pull-up resistor is 80 kΩ, and the pull-down resistor is 40 kΩ.
[0017] Figure 1 In the circuit of , the filter capacitors C1 and C2 are selected to be 68 pF.
[0018] Combined with Figure 2 , the sampling steps are as follows:
[0019] The internal pull-up of the CAI1 port, one end of the reed switch S1 is connected to GND. When S1 is closed, the outside of CAI1 is grounded, the detection port changes from high level to low level, the falling edge triggers an interruption, the single-chip microcomputer records the state, and makes the CAI1 port pull down and the CAI2 port pull up. The levels at both ends of the reed switch S1 are the same, without power consumption, and the levels at both ends of the reed switch S2 are different, waiting for the external trigger to close the reed switch.
[0020] The internal pull-up of the CAI2 port, one end of the reed switch S2 is connected to GND. When S2 is closed, the outside of CAI2 is grounded, the detection port changes from high level to low level, the falling edge triggers an interruption, the single-chip microcomputer records the state, and makes the CAI2 port pull down and the CAI1 port pull up. The levels at both ends of the reed switch S2 are the same, without power consumption, and the levels at both ends of the reed switch S1 are different, waiting for the external trigger to close the reed switch.
[0021] When CAI1 and CAI2 are triggered once respectively, the counting is considered valid, the water volume is incremented by one, and the sampling interlock improves the accuracy.
[0022] When the single-chip microcomputer is in the working state (the single-chip microcomputer is normally in the sleep state and wakes up to work once every two seconds), check the port status. If all are high levels, it means that the reed switch is in the open state and has no power consumption. If a certain port is at a low level, the reed switch is triggered to close, and it is judged when the reed switch opens. If it opens, the sampling port is restored to the pull-up state and has no power consumption; if it does not open, it remains in the pull-down state to reduce power consumption.
[0023] Only the moment when the reed switch closing state is judged consumes current. The current of the reed switch is about 5 mA, the judgment duration is about 1 μs, and it is judged once every 2 s. Therefore, the average current in the long-term closed state of the reed switch is about 0.0025 μA.
[0024] If a single reed switch closes and opens in a loop multiple times, an error is reported and its use is stopped.
[0025] If a strong magnetic field causes the two reed switches S1 and S2 to close simultaneously, an error is reported and its use is stopped.
[0026] In this technical solution, no judgment is made in the normal working state, and the single-chip microcomputer is externally triggered to interrupt for sampling and counting. Only when the base meter stops and is exactly in the state of triggering a single reed switch to close, a judgment is made at a certain interval, further reducing power consumption.
[0027] The sampling circuit of the present utility model uses the internal pull-up and pull-down switching of the single-chip microcomputer to perform sampling monitoring and reduce the power consumption of the circuit, reduce the components of the peripheral circuit, and improve the response speed and accuracy.
[0028] The above shows and describes the basic principles, main features and advantages of the present utility model. Those skilled in the art of this industry should understand that the present utility model is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principle of the present utility model. Without departing from the spirit and scope of the present utility model, the present utility model will have various changes and improvements, and these changes and improvements all fall within the scope of the present utility model claimed. The scope of protection claimed by the present utility model is defined by the appended claims and their equivalents.
Claims
1. A low-power sampling circuit for a reed switch terminal of an intelligent water meter, characterized in that: It includes a reed switch S1 and a reed switch S2; one end of the reed switch S1 is connected to GND, the other end is connected to the single-chip microcomputer sampling port CAI1, and is connected to GND through a filtering capacitor C1; one end of the reed switch S2 is connected to GND, the other end is connected to the single-chip microcomputer sampling port CAI2, and is connected to GND through a filtering capacitor C1; the single-chip microcomputer is HC32L136.
2. The low-power consumption sampling circuit for the reed switch terminal of an intelligent water meter according to claim 1, wherein: The internal pull-up resistor of the single-chip microcomputer HC32L136 is 80 kΩ, and the pull-down resistor is 40 kΩ.
3. The low-power sampling circuit for the reed switch terminal of an intelligent water meter according to claim 1, characterized in that: Both the capacitor C1 and the capacitor C2 are 68 pF.