Water leakage detection circuit

Abstract

The utility model discloses a water leakage detection circuit, which relates to the field of water leakage detection and is characterized in that a detection electrode is arranged in a to-be-detected area where water leakage needs to be detected, a first electrode is grounded, and a second electrode is connected with the output end of a power supply. A closed loop is formed between the first electrode and the second electrode due to the conductivity of water; meanwhile, one end of the second electrode is connected with the first input end of the comparator, and the comparator determines whether the to-be-detected area leaks water or not by comparing the preset reference voltage with the voltage of the connection point between the second electrode. The comparator can rapidly and accurately detect tiny water leakage conditions, the sensitivity and the response speed of the water leakage detection circuit are improved, meanwhile, the protection module is arranged to guarantee normal work of the detection electrode, the stability and the reliability of the whole water leakage detection circuit are improved, and by setting and flexibly adjusting the magnitude of the preset reference voltage, the water leakage detection circuit is more stable and reliable. Water leakage detection under different water quality scenes can be realized, and the application range is wide.

Description

TECHNICAL FIELD

[0001] The utility model relates to water leakage detection field, especially a water leakage detection circuit. BACKGROUND

[0002] In modern life and industrial production, water leakage problems can cause serious losses, such as building damage, equipment failure, water resource waste, etc. Therefore, how to carry out water leakage detection has become an important development direction at present, which has important significance for guaranteeing the safety of buildings and related facilities, normal use, and resource saving, etc. At present, sound vibration method or regional water meter setting method is used to realize water leakage detection. The sound vibration method can realize water leakage detection by using the vibration caused by the water leakage point. The regional water meter setting method detects whether there is water leakage loss in the region by comparing the flow into the region and the flow out of the region. At present, these water leakage detection methods still have some deficiencies. The sensitivity of the whole water leakage detection is relatively low, the stability is relatively poor, and the response speed is slow, which is difficult to meet the precision and timeliness requirements of water leakage detection in actual application. UTILITY MODEL CONTENTS

[0003] The utility model aims at providing a water leakage detection circuit, which can effectively solve the problem of water leakage detection and realize high-precision and high-timeliness water leakage detection.

[0004] To solve the above technical problems, the utility model provides a water leakage detection circuit, which comprises:

[0005] At least one group of detection electrodes, a group of the detection electrodes comprises a first electrode and a second electrode; one end of the first electrode is connected with a first preset power supply; the detection electrodes are arranged in a to-be-detected region;

[0006] A comparator, a first input end is connected with an output end of a power supply and one end of the second electrode respectively, a second input end is connected with a preset reference voltage, and an output end is used as an output end of a water leakage detection circuit and is used for comparing the preset reference voltage and a connection point voltage between itself and the second electrode to realize water leakage detection;

[0007] A protection module, a first end is connected with one end of the first electrode, a second end is connected with one end of the second electrode, and the protection module is used for limiting the voltage on the detection electrodes to protect the detection electrodes.

[0008] Optionally, the water leakage detection circuit further comprises:

[0009] A power supply filtering module, an input end is connected with an output end of the power supply, and output ends are connected with a first input end of the comparator and one end of the second electrode respectively, and the power supply filtering module is used for filtering out the noise in the power supply.

[0010] Optionally, the power filtering module comprises:

[0011] a filtering resistor, a first end of which is connected to an output end of the power supply;

[0012] a filtering capacitor, a first end of which is grounded, and a second end of which is connected to a second end of the filtering resistor, a first input end of the comparator and one end of the second electrode respectively.

[0013] Optionally, the protection module comprises:

[0014] a first bidirectional transient voltage suppression diode, a first end of which is connected to one end of the first electrode, and a second end of which is grounded;

[0015] a second bidirectional transient voltage suppression diode, a first end of which is connected to one end of the second electrode, the first input end of the comparator and the output end of the power supply respectively, and a second end of which is grounded.

[0016] Optionally, the protection module further comprises:

[0017] a current limiting module, a first end of which is connected to one end of the first electrode and the first end of the first bidirectional transient voltage suppression diode respectively, and a second end of which is grounded, for limiting the current flowing through the detection electrode.

[0018] Optionally, the current limiting module is a current limiting resistor.

[0019] Optionally, the system further comprises:

[0020] an alarm module, an input end of which is connected to an output end of the comparator, for alarming based on a preset alarm strategy when the comparison result of the comparator is that there is water leakage.

[0021] Optionally, the system further comprises:

[0022] a reference voltage generation module, an input end of which is connected to an output end of a second preset power supply, and an output end of which is connected to a second input end of the comparator, for generating a preset reference voltage required for water leakage detection based on the second preset power supply.

[0023] Optionally, the reference voltage generation module comprises:

[0024] a first voltage dividing resistor, a first end of which is connected to the output end of the second preset power supply;

[0025] a second voltage dividing resistor, a first end of which is connected to a second end of the first voltage dividing resistor and the second input end of the comparator respectively, and a second end of which is grounded.

[0026] Optionally, the reference voltage generation module further comprises:

[0027] A reserved resistance has a first end connected to a second end of the second voltage dividing resistance and a second end grounded.

[0028] The utility model provides a kind of water leakage detection circuit, detection electrode is arranged in the to-be-detected area needing to detect water leakage, wherein, one end of first electrode is grounded, one end of second electrode is connected with the output end of power supply, when the to-be-detected area exists water leakage condition, closed loop will be formed between first electrode and second electrode due to the conductivity of water;While one end of second electrode is connected with the first input end of comparator, comparator determines whether the to-be-detected area has water leakage by comparing the connection point voltage between preset reference voltage and second electrode. Comparator can quickly and accurately detect tiny water leakage condition, improve the sensitivity and response speed of water leakage detection circuit, meanwhile, protection module is arranged to ensure the normal work of detection electrode, improve the stability and reliability of entire water leakage detection circuit, by setting and flexibly adjusting the size of preset reference voltage, water leakage detection under different water quality scenes can be realized, and the scope of application is wide. BRIEF DESCRIPTION OF DRAWINGS

[0029] In order to more clearly illustrate the technical scheme in the embodiments of the utility model, the drawings needed to be used in the prior art and the embodiments will be simply introduced below, obviously, the drawings in the following description are only some embodiments of the utility model, and for those skilled in the art, other drawings can be obtained without creative labor on the basis of these drawings.

[0030] Figure 1 The utility model provides a kind of water leakage detection circuit's structural schematic diagram;

[0031] Figure 2 The utility model provides a kind of water leakage detection circuit's circuit structure schematic diagram. DETAILED DESCRIPTION

[0032] The core of the utility model is to provide a kind of water leakage detection circuit, can quickly, accurately detect tiny water leakage condition, improve the sensitivity and response speed of water leakage detection circuit, meanwhile, protection module is arranged to ensure the normal work of detection electrode, improve the stability and reliability of entire water leakage detection circuit, by setting and flexibly adjusting the size of preset reference voltage, water leakage detection under different water quality scenes can be realized, and the scope of application is wide.

[0033] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme of the embodiments of the utility model will be described clearly and completely in combination with the drawings in the embodiments of the utility model below. Obviously, the described embodiments are part of the embodiments of the utility model, rather than all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by those skilled in the art without creative labor belong to the protection scope of the utility model.

[0034] Please refer to Figure 1 , Figure 1 The utility model provides a kind of structure schematic diagram of water leakage detection circuit;Please refer to Figure 2 , Figure 2 The utility model provides a kind of circuit structure schematic diagram of water leakage detection circuit. To solve the above technical problems, the utility model provides a kind of water leakage detection circuit, comprising:

[0035] At least one set of detection electrode, a set of detection electrode includes first electrode J1 and second electrode J2;One end of first electrode J1 is connected to first preset power supply V1;Detection electrode is set to be detected area;

[0036] Comparator U1, first input end is connected with the output end of power supply VIN and one end of second electrode J2 respectively, second input end is connected to preset reference voltage Vf, output end is as the output end OUT of water leakage detection circuit, for comparing preset reference voltage Vf and the voltage of connecting point between itself and second electrode J2 to realize water leakage detection;

[0037] Protection module PRT, first end is connected with one end of first electrode J1, second end is connected with one end of second electrode J2, for limiting voltage on detection electrode, to protect detection electrode.

[0038] It can be understood that the detection electrode is placed at a position where water leakage needs to be detected, and the detection electrode includes the first electrode J1 and the second electrode J2, both of which are placed in a to-be-detected area where water leakage needs to be detected. When water leakage occurs, water forms a conductive path between the first electrode J1 and the second electrode J2, thereby changing the potential of the connection point between the second electrode J2 and the first input terminal of the comparator U1. The power supply terminal Vs+ of the comparator U1 is connected to the power supply VIN, and the ground terminal Vs- is grounded. The potential of the second input terminal of the comparator U1 always remains consistent with the preset reference voltage Vf connected. When there is no water leakage, the first electrode J1 and the second electrode J2 are in an open circuit state, and the potential of the first input terminal of the comparator U1 depends on the output voltage of the connected power supply VIN and remains substantially consistent with the output voltage of the connected power supply VIN. When water leakage occurs, water forms a conductive path between the first electrode J1 and the second electrode J2, and the first preset power supply V1 connected to the first electrode J1 is connected to the first input terminal of the comparator U1, thereby changing the potential of the first input terminal of the comparator U1. Therefore, by setting a suitable preset reference voltage Vf, the comparator U1 can effectively identify the change in the potential of the first input terminal, thereby achieving water leakage detection and further informing other processing modules or control modules of the water leakage condition of the to-be-detected area through different output signals.

[0039] It should be noted that the specific implementation of the detection electrode and the specific number of electrodes are not particularly limited in the present application. One specific embodiment is that the first electrode J1 and the second electrode J2 are both implemented by one electrode, i.e., one set of detection electrodes includes two electrodes. The second electrode J2 can also be implemented by one electrode, and the first electrode J1 includes a plurality of sub-electrodes, which are uniformly arranged around the second electrode J2 to detect water leakage in a large area. Multiple sets of detection electrodes can also be independently set to detect water leakage in different positions or areas. The specific type and placement of the electrodes are not particularly limited in the present application and can be implemented by a conductive material such as metal. The to-be-detected area and the placement position of the detection electrode can be determined according to the specific detection object and environment, including the surrounding of the water pipe, the bottom or edge of the pool or water tank, the low-lying place of the building, and the equipment room.

[0040] It should be further explained that the specific type and implementation of the first preset power supply V1 and the power supply voltage are not particularly limited herein, the output voltage of the first preset power supply V1 is not equal to the output voltage of the power supply VIN, and generally the output voltage is less than the output voltage of the power supply VIN, and the ground (GND) can be used for implementation; the specific value of the preset reference voltage Vf is not particularly limited herein, and can be selected and set according to the actual application scene, and the preset reference voltage Vf is selected to be an intermediate potential between the output voltage of the first preset power supply V1 and the output voltage of the power supply VIN, so that the comparator U1 can output different voltage signals in the two cases of water leakage and no water leakage, and the water leakage alarm is more intuitive. For example, the output voltage of the first preset power supply V1 is less than the output voltage of the power supply VIN, the preset reference voltage Vf is slightly less than the output voltage of the power supply VIN, and greater than the output voltage of the first preset power supply V1. The first input terminal of the comparator U1 is a same-phase input terminal, and the second input terminal is an inverse-phase input terminal. When there is no water leakage, the first electrode J1 and the second electrode J2 remain open circuit. Since the preset reference voltage Vf is less than the output voltage of the power supply VIN, the comparator U1 outputs a high-level signal; when there is water leakage, the first electrode J1 and the second electrode J2 are conductive, and the voltage at the first input terminal of the comparator U1 is pulled down to the first preset power supply V1. At this time, the comparator U1 outputs a low-level signal.

[0041] It is not difficult to understand that in order to ensure the normal work of the detection electrode, a protection module PRT is also arranged in the water leakage detection circuit. The specific type and implementation of the protection module PRT are not particularly limited herein, and are not limited to the overvoltage protection function indicated in the embodiment. The protection module PRT can also be used for overcurrent protection, electrostatic protection, electromagnetic interference protection and the like. The specific type and implementation of the comparator U1 are not particularly limited herein. The comparator U1 has high-precision signal detection and processing capability, can perceive extremely weak electric signal changes, and can quickly process and judge the input signal. Once the electric signal change between the detection electrodes is detected, it will quickly compare it with the preset reference voltage Vf and output the corresponding result. The comparator U1 also has certain stability and anti-interference capability, ensuring the accuracy and reliability of the water leakage detection. The SGM8701 type comparator U1 can be used for implementation.

[0042] As a specific embodiment, as Figure 2As shown, the water leakage detection circuit comprises a comparator U1, a power supply module, a detection electrode, a reference voltage generation module and a protection module PRT, the detection electrode comprises a first electrode J1 and a second electrode J2, the power supply module provides a stable power supply VIN, the reference voltage generation module comprises a first voltage dividing resistor Rf1, a second voltage dividing resistor Rf2 and a reserved resistor Rf0, and the protection module PRT comprises two bidirectional transient voltage suppression diodes. The non-inverting input end Vin+ of the comparator U1 is connected to the power supply VIN through a filtering resistor R1 of 1MΩ, and is connected to the second electrode J2 of the detection electrode through a connection point; the inverting input end Vin- of the comparator U1 is connected to the output end of the reference voltage generation module, and the output end Vout outputs a detection signal. When there is no water leakage, the first electrode J1 and the second electrode J2 are in an open circuit state, and the potential of the non-inverting input end Vin+ of the comparator U1 is determined by the power supply VIN; when water leakage occurs, water forms a conductive path between the first electrode J1 and the second electrode J2, changes the potential of the non-inverting input end Vin+, and the potential of the inverting input end Vin- is determined after being divided by the first voltage dividing resistor Rf1, the second voltage dividing resistor Rf2 and the reserved resistor Rf0 in the reference voltage generation module. In a detection process, the preset reference voltage Vf generated after voltage division is a fixed potential, the comparator U1 compares the potential difference between the non-inverting input end and the inverting input end, and outputs a corresponding detection signal at the output end Vout, so that whether water leakage occurs can be judged by detecting the signal.

[0043] The utility model provides a kind of water leakage detection circuit based on comparator U1, can quickly, accurately detect water leakage situation, and provide reliable detection signal. Detection sensitivity is high, can quickly, accurately detect tiny water leakage situation. Good stability, through the setting of power filter module and protection module PRT, effectively improve the anti-interference ability and stability of circuit. Simple structure, cost is lower, easy to realize and popularization and application.

[0044] On the basis of the above embodiment:

[0045] As an optional embodiment, further comprising:

[0046] Power filter module, input end is connected with the output end of power supply VIN, and the output end is connected with the first input end of comparator U1 and one end of second electrode J2 respectively, for filtering the noise in power supply VIN.

[0047] It is understandable that the water leakage detection circuit can further be provided with a power filter module connected with the output end of the power supply VIN. The power filter module can filter various noises existing in the power supply voltage during the power supply process, prevent electromagnetic interference, and stabilize the output voltage of the power supply VIN. The specific type and implementation of the power filter module are not particularly limited in the present application. Low-pass filtering and other methods can be used to filter high-frequency noise components in the power supply, making the output DC voltage more pure and providing a stable and clean power supply for the water leakage detection circuit.

[0048] Specifically, the power filter module is added to avoid noise entering the water leakage detection circuit, thereby preventing detection errors caused by noise interference and improving the accuracy and reliability of water leakage detection.

[0049] As an optional embodiment, the power filter module comprises:

[0050] A filter resistor R1 is connected with the output end of the power supply VIN at the first end.

[0051] A filter capacitor is grounded at the first end and connected with the second end of the filter resistor R1, the first input end of the comparator U1, and one end of the second electrode J2 at the second end.

[0052] It is understood that the RC filter circuit composed of the filter resistor R1 and the filter capacitor can be used to realize the power filter module. The filter resistor R1 is connected in series between the output end of the power supply VIN and the first input end of the comparator U1, which can further limit the current output from the power supply VIN to the comparator U1 and protect the circuit. The filter capacitor can maintain the relative stability of the output voltage by releasing or absorbing charges when the output voltage of the power supply VIN fluctuates, ensuring that the circuit and components for water leakage detection always work at appropriate voltages, avoiding the influence of voltage fluctuations on the performance and reliability of the entire circuit and device. The specific type and implementation of the filter resistor R1 and the filter capacitor are not particularly limited in the present application. SMD resistors and SMD capacitors can be used to realize the filter resistor R1 and the filter capacitor. The specific values of the resistance of the filter resistor R1 and the capacitance of the filter capacitor are not particularly limited in the present application. They can be selected and set according to actual filtering requirements. The resistance of the filter resistor R1 can be 1MΩ, and the capacitance of the filter capacitor can be 0.1μF.

[0053] Specifically, the RC filter circuit formed by the filter resistor R1 and the filter capacitor can effectively realize filtering of the power supply VIN, and the resistance value of the filter resistor R1 and the capacitance value of the filter capacitor can be adjusted according to application requirements, so that different filtering intervals are realized, and the flexibility is high, and the application range is wide. The structure of the entire power filtering module is simple, easy to implement, the cost of the device used is low, and the volume is small, which is beneficial to the simple implementation of the entire water leakage detection circuit, and facilitates integration and miniaturized application.

[0054] As an optional embodiment, the protection module PRT comprises:

[0055] A first bidirectional transient voltage suppression diode D1, a first end of which is connected with one end of the first electrode J1, and a second end of which is grounded;

[0056] A second bidirectional transient voltage suppression diode D2, a first end of which is connected with one end of the second electrode J2, a first input end of the comparator U1 and an output end of the power supply VIN respectively, and a second end of which is grounded.

[0057] It can be understood that the protection module PRT can be implemented by two bidirectional transient voltage suppression diodes, which are arranged between the first electrode J1 and the ground GND and between the second electrode J2 and the ground GND respectively, for protecting the circuit from the impact of ESD (Electro-Static discharge) and other transient high voltage. When an excessively high voltage appears on the first electrode J1 or the second electrode J2, the corresponding bidirectional transient voltage suppression diode is turned on, and the excessively high voltage is clamped to a safe range, so as to prevent the circuit components, especially the electrodes, from being damaged. The specific type and implementation manner of the first bidirectional transient voltage suppression diode D1 and the second bidirectional transient voltage suppression diode D2 are not particularly limited in the present application, and a Zener diode, a semiconductor discharge tube or other overvoltage protection devices can also be used to implement the protection module PRT. As shown in FIG. 1, two bidirectional transient voltage suppression diodes of the ESD9B5.0ST5G type can be used to implement the protection module PRT. Figure 2

[0058] Specifically, the protection module PRT is implemented by the bidirectional transient voltage suppression diode, which can effectively prevent the influence of static electricity and instantaneous pulse voltage on the detection electrode, realize overvoltage protection of the detection electrode, and at the same time, the detection electrode is well grounded by the bidirectional transient voltage suppression diode, so that the static electricity is introduced into the ground in time, and the charge accumulation is avoided. The structure is simple, easy to implement, the cost of the device used is low, and the volume is small, which is beneficial to the simple implementation of the entire water leakage detection circuit, and facilitates integration and miniaturized application.

[0059] As an optional embodiment, the protection module PRT further comprises:

[0060] ​The current limiting module has its first terminal connected to one end of the first electrode J1 and the first terminal of the first bidirectional transient voltage suppression diode D1, and its second terminal grounded, which is used to limit the current flowing through the detection electrode.

[0061] It is understandable that the protection module PRT can also achieve overcurrent protection for the detection electrodes by adding a current limiting module. The current limiting module is connected in series in the conducting loop formed by the first electrode J1 and the second electrode J2, which can effectively limit the current flowing through the first electrode J1 and the second electrode J2 in the event of leakage, thus protecting the circuit. This application does not make any special restrictions on the specific type and implementation method of the current limiting module.

[0062] Specifically, by connecting a current limiting module in series in the conducting circuit formed by the first electrode J1 and the second electrode J2 in the event of leakage, overcurrent protection for the detection electrode is achieved, which further improves the safety and reliability of the detection electrode and ensures the safety of the entire leakage detection circuit.

[0063] As an optional embodiment, the current limiting module is a current limiting resistor R2.

[0064] It's easy to understand that the current limiting module can be implemented using a current-limiting resistor R2, such as... Figure 2 As shown, the current-limiting resistor R2 is connected between the first electrode J1 and ground GND. It not only limits the current but also acts as a bias resistor. The bias provided by the current-limiting resistor R2 supplies a suitable bias current to the detection electrode, which, in conjunction with the comparator U1, enables leakage detection, ensuring the stability and safety of the electrode input signal. This application does not impose specific limitations on the specific resistance value and implementation method of the current-limiting resistor R2; a 10kΩ surface-mount resistor can be used.

[0065] Specifically, the current-limiting resistor R2 can effectively protect the detection electrode from overcurrent and provide a suitable bias for the detection electrode. The structure is simple and easy to implement. The components used are low-cost and small in size, which is conducive to the simple implementation of the entire water leakage detection circuit and facilitates integration and miniaturization.

[0066] As an optional embodiment, it also includes:

[0067] The alarm module, with its input terminal connected to the output terminal of comparator U1, is used to trigger an alarm based on a preset alarm strategy when the comparison result of comparator U1 indicates that there is a water leak.

[0068] It can be understood that when the water leakage is detected, the output end Vout of the comparator U1 outputs a corresponding signal, which can be transmitted to the alarm module to realize the alarm of the water leakage, or can be transmitted to the subsequent signal processing circuit or control system to realize the alarm or control of the water leakage by controlling the corresponding alarm module. The specific type and implementation of the alarm module are not particularly limited in the present application, and the preset alarm strategy also has multiple choices, such as audible and visual alarm, prompt light and the like. The water leakage detection circuit can further be provided with a display module to display the water leakage detection result, a communication module to report the water leakage detection result to a remote server and the like, a storage module to store the water leakage detection result, and a shell to ensure the safety of the water leakage detection circuit, which are not particularly limited in the present application.

[0069] Specifically, the alarm module is set to help the staff to timely find the water leakage anomaly, so as to timely take corresponding measures to avoid accidents and reduce losses.

[0070] As an optional embodiment, the water leakage detection circuit further comprises:

[0071] The reference voltage generation module is connected with the output end of the second preset power supply at the input end and connected with the second input end of the comparator U1 at the output end, and is used to generate the preset reference voltage Vf required for water leakage detection based on the second preset power supply.

[0072] It is not difficult to understand that the comparator U1 needs the preset reference voltage Vf as the detection basis and detection foundation during water leakage detection, and therefore the reference voltage generation module can be directly arranged in the water leakage detection circuit. The reference voltage generation module arranged in the water leakage detection circuit can also be more convenient for the operator to adjust the value of the preset reference voltage Vf outputted thereby, so as to realize the detection of water leakage in different water quality conditions. For example, when the water leakage detection circuit is applied in a good water quality scene, the resistance value of the leaked water is relatively large. At this time, the potential of the first input end of the comparator U1 in the water leakage condition is higher than that in the poor water quality condition. Therefore, by setting different preset reference voltages Vf, the water leakage detection in different water quality scenes can be realized, and the accurate detection of water leakage in a specific water quality in the same scene can also be realized. The specific type and implementation of the reference voltage generation module are not particularly limited in the present application, and the specific value of the second preset power supply and the preset reference voltage Vf are not particularly limited in the present application. The second preset power supply can directly reuse the power supply VIN connected with the comparator U1.

[0073] Specifically, the reference voltage generation module is set to realize the generation of the preset reference voltage Vf, and can also effectively improve the flexibility of the water leakage detection circuit and expand the applicable scene of the water leakage detection circuit.

[0074] As an optional embodiment, the reference voltage generation module comprises:

[0075] The first voltage dividing resistor Rf1 has a first end connected to the output end of the second preset power supply.

[0076] The second voltage dividing resistor Rf2 has a first end connected to the second end of the first voltage dividing resistor Rf1 and the second input end of the comparator U1 respectively, and a second end grounded.

[0077] It can be understood that the reference voltage generation module can be specifically implemented by using the voltage dividing circuit composed of the first voltage dividing resistor Rf1 and the second voltage dividing resistor Rf2, the first voltage dividing resistor Rf1 and the second voltage dividing resistor Rf2 are connected in series, and are connected between the second preset power supply and the ground after being connected in series, so as to divide the output voltage of the second preset power supply to generate the preset reference voltage Vf, and transmit the divided voltage signal to the second input end of the comparator U1, so that the comparator U1 can compare the voltage from the detection electrode. The specific type and implementation manner of the first voltage dividing resistor Rf1 and the second voltage dividing resistor Rf2 are not particularly limited in the present application, and the resistance value can be set and adjusted according to the size of the preset reference voltage Vf and the size of the output voltage of the second preset power supply. Taking an example that the preset reference voltage Vf is half of the output voltage of the second preset power supply, the first voltage dividing resistor Rf1 and the second voltage dividing resistor Rf2 are both implemented by using a 1MΩ chip resistor.

[0078] Specifically, by setting the first voltage dividing resistor Rf1 and the second voltage dividing resistor Rf2 connected in series, the generation of the preset reference voltage Vf can be effectively realized, the resistance value of the resistor can be directly adjusted to realize the adjustment of the preset reference voltage Vf, the structure is simple and easy to realize, the cost of the device used is low, the volume is small, and it is conducive to the simple realization of the whole water leakage detection circuit, and convenient integration and miniaturization application.

[0079] As an optional embodiment, the reference voltage generation module further comprises:

[0080] The reserved resistor Rf0 has a first end connected to the second end of the second voltage dividing resistor Rf2 and a second end grounded.

[0081] It is not difficult to understand that, in order to realize more flexible reference voltage generation module, a reserved resistance Rf0 can also be directly set in the circuit design stage of the water leakage detection circuit, the reserved resistance Rf0 itself can be realized by 0 Ω resistance, when the preset reference voltage Vf needs to be adjusted, the reserved resistance Rf0 can be removed and replaced to realize voltage adjustment, without re-designing the circuit and changing the position of other elements, providing higher flexibility for circuit debugging and optimization; the current in the reference voltage generation module can also be monitored by measuring the voltage drop across the reserved resistance Rf0, so as to discover circuit failure in time; at the same time, the 0 Ω resistance can also play a role in suppressing electromagnetic interference and circuit protection.

[0082] Specifically, by increasing the reserved resistance Rf0 in the reference voltage generation module, the flexibility and reliability of the entire water leakage detection circuit are further improved, the application of the water leakage detection circuit in different scenarios is facilitated, the circuit design is optimized, and the design cost of the circuit is reduced; the structure is simple, easy to implement, the cost of the device used is low, and the volume is small, which is conducive to the simple implementation of the entire water leakage detection circuit.

[0083] Each embodiment in the specification is described in a progressive manner, and each embodiment focuses on the difference from other embodiments. The same or similar parts between each embodiment can be referred to each other. It should be noted that, in the specification, the relationship terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between the entities or operations. Moreover, the term "include", "contain" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or equipment. Without more limitations, the element defined by the statement "including a" does not exclude the presence of another identical element in the process, method, article or equipment including the element.

[0084] The above description of disclosed embodiments enables one skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein can be applied to other embodiments without departing from the spirit or scope of the application. The above description is intended to be illustrative and not restrictive. Many other embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of the application should, therefore, be determined not with reference to the above description, but instead with reference to the appended claims, along with their full scope of equivalents.

Claims

1. A water leak detection circuit, characterized by, The application relates to a water leakage detection circuit. At least one set of detection electrodes, one set of the detection electrodes comprising a first electrode and a second electrode; one end of the first electrode being connected to a first preset power supply; The detection electrodes are arranged in a region to be detected; A comparator, a first input end of the comparator being connected to an output end of the power supply and one end of the second electrode, a second input end of the comparator being connected to a preset reference voltage, and an output end of the comparator being used as an output end of the water leakage detection circuit and for comparing the preset reference voltage and a voltage at a connection point between the second electrode and the output end of the comparator to realize water leakage detection; A protection module, a first end of the protection module being connected to one end of the first electrode, and a second end of the protection module being connected to one end of the second electrode, the protection module being used for limiting a voltage on the detection electrodes to protect the detection electrodes.

2. The water leak detection circuit of claim 1, wherein, Further comprising: A power supply filtering module, an input end of the power supply filtering module being connected to an output end of the power supply, and output ends of the power supply filtering module being connected to the first input end of the comparator and one end of the second electrode respectively, the power supply filtering module being used for filtering out noise in the power supply.

3. The leak detection circuit of claim 2, wherein, The power supply filtering module comprises: A filtering resistor, a first end of the filtering resistor being connected to the output end of the power supply; A filtering capacitor, a first end of the filtering capacitor being grounded, and a second end of the filtering capacitor being connected to the second end of the filtering resistor, the first input end of the comparator and one end of the second electrode respectively.

4. The leak detection circuit of claim 1, wherein The protection module comprises: A first bidirectional transient voltage suppression diode, a first end of the first bidirectional transient voltage suppression diode being connected to one end of the first electrode, and a second end of the first bidirectional transient voltage suppression diode being grounded; A second bidirectional transient voltage suppression diode, a first end of the second bidirectional transient voltage suppression diode being connected to one end of the second electrode, the first input end of the comparator and the output end of the power supply respectively, and a second end of the second bidirectional transient voltage suppression diode being grounded.

5. The leak detection circuit of claim 4, wherein, The protection module further comprises: A current limiting module, a first end of the current limiting module being connected to one end of the first electrode and the first end of the first bidirectional transient voltage suppression diode respectively, and a second end of the current limiting module being grounded, the current limiting module being used for limiting current flowing through the detection electrodes.

6. The leak detection circuit of claim 5, wherein, The current limiting module is a current limiting resistor.

7. The leak detection circuit of claim 1, wherein, Further comprising: An alarm module, an input end of the alarm module being connected to the output end of the comparator, the alarm module being used for alarming based on a preset alarm strategy when a comparison result of the comparator is that water leakage exists.

8. The leak detection circuit according to any one of claims 1 to 7, wherein Further comprising: A reference voltage generating module, an input end of the reference voltage generating module being connected to an output end of a second preset power supply, and an output end of the reference voltage generating module being connected to the second input end of the comparator, the reference voltage generating module being used for generating a preset reference voltage required for water leakage detection based on the second preset power supply.

9. The leak detection circuit of claim 8, wherein, The reference voltage generating module comprises: A first voltage dividing resistor, a first end of the first voltage dividing resistor being connected to the output end of the second preset power supply; A second voltage dividing resistor, a first end of the second voltage dividing resistor being connected to the second end of the first voltage dividing resistor and the second input end of the comparator respectively, and a second end of the second voltage dividing resistor being grounded.

10. The leak detection circuit of claim 9, wherein, The reference voltage generating module further comprises: A reserved resistor, a first end of the reserved resistor being connected to the second end of the second voltage dividing resistor, and a second end of the reserved resistor being grounded.

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