Sound production part detection circuit and method, alarm and fire alarm system

Abstract

The invention discloses a sounding component detection circuit and method, an alarm and a fire alarm system. The sounding component detection circuit comprises a main control module, a detection module and a sounding component. The main control module is used for sending pulse signals; the signal input end of the detection module is connected with the master control module and used for receiving pulse signals. The signal output end of the detection module is connected with the main control module and is used for outputting a feedback signal to the main control module; the first end of the sounding component is connected with the charge-discharge end of the detection module, and the second end of the sounding component is grounded; and the main control module is used for determining whether the sound production component fails or not according to the feedback signal. The invention provides a sound production component fault detection mode different from the prior art, in the detection mode, a driving module does not need to participate in driving the sound production component to operate, an original normal working circuit of the sound production component does not need to be changed, and the detection circuit is simple in structure.

Description

Technical Field

[0001] This application relates to the field of electronic circuit technology, and in particular to a sound-generating component detection circuit and method, an alarm, and a fire alarm system. Background Technology

[0002] Currently, in existing technology, electrical devices such as alarms typically include sound-emitting components, such as buzzers, to emit an alarm sound. When smoke appears in the external environment, the buzzer can sound an alarm, alerting people to evacuate quickly and extinguish the fire promptly. In practice, when a buzzer malfunctions, it may fail to sound an alarm even in the presence of smoke, posing a threat to people's lives and property. Therefore, it is necessary to regularly check buzzers for malfunctions.

[0003] In the existing technology, when detecting faults in a buzzer, it is necessary to drive the buzzer through a driver module. However, in this detection method, the driver module needs to participate in the detection process, and the operation of the buzzer during the detection process increases the ambient noise, resulting in a poor testing experience. Summary of the Invention

[0004] The purpose of this application is to provide a detection circuit and method for sound-generating components, an alarm, and a fire alarm system, which do not require a driver module to drive the operation of the sound-generating components when performing fault detection on the sound-generating components.

[0005] The embodiments of this application are implemented as follows: In a first aspect, this application provides a sound-generating component detection circuit, including a main control module, a detection module, and a sound-generating component; the main control module is used to emit pulse signals; the signal input terminal of the detection module is connected to the main control module and is used to receive pulse signals; the signal output terminal of the detection module is connected to the main control module and is used to output feedback signals to the main control module; the first end of the sound-generating component is connected to the charging and discharging terminal of the detection module, and the second end of the sound-generating component is grounded; the main control module is used to determine whether the sound-generating component has malfunctioned based on the feedback signal. In one embodiment, the detection module includes a charging unit and a signal output unit; wherein, the input terminal of the charging unit is the signal input terminal of the detection module, and the output terminal of the charging unit is the charging and discharging terminal of the detection module; the input terminal of the signal output unit is connected to the output terminal of the charging unit, and the output terminal of the signal output unit is the signal output terminal of the detection module.

[0006] In one embodiment, the charging / discharging terminal of the detection module is connected to the first terminal of the sound-generating component, and the connection terminal of the detection module is connected to the second terminal of the sound-generating component; the detection module further includes a grounding unit; the first terminal of the grounding unit is connected to the input terminal of the charging unit, the second terminal of the grounding unit is the connection terminal of the detection module, and the third terminal of the grounding unit is grounded as the grounding terminal; the second terminal of the sound-generating component is grounded through the grounding unit.

[0007] In one embodiment, the charging unit includes a first diode, the anode of which is the input terminal of the charging unit, and the cathode of which is the output terminal of the charging unit.

[0008] In one embodiment, the charging unit includes a first diode and a first current limiting unit; the anode of the first diode is the input terminal of the charging unit, the cathode of the first diode is connected to the first terminal of the first current limiting unit, and the second terminal of the first current limiting unit is the output terminal of the charging unit; or, the first terminal of the first current limiting unit is the input terminal of the charging unit, the second terminal of the first current limiting unit is connected to the anode of the first diode, and the cathode of the first diode is the output terminal of the charging unit.

[0009] In one embodiment, the first current limiting unit includes a first current limiting resistor, the first end of the first current limiting resistor being the first end of the first current limiting unit, and the second end of the first current limiting resistor being the second end of the first current limiting unit.

[0010] In one embodiment, the signal output unit includes a first switching transistor, a second current limiting unit, and a pull-up unit. The first terminal of the second current limiting unit is the input terminal of the signal output unit, and the second terminal of the second current limiting unit is connected to the first pin of the first switching transistor. The second pin of the first switching transistor is the output terminal of the signal output unit, and the second pin is connected to the power module through the pull-up unit. The third pin of the first switching transistor is grounded. Alternatively, the signal output unit includes a first switching transistor and a second current limiting unit. The first terminal of the second current limiting unit is the input terminal of the signal output unit, and the second terminal of the second current limiting unit is connected to the first pin of the first switching transistor. The second pin of the first switching transistor is the output terminal of the signal output unit. The third pin of the first switching transistor is grounded.

[0011] In one embodiment, the second current limiting unit includes a second current limiting resistor, the first end of which is the first end of the second current limiting unit, and the second end of which is the second end of the second current limiting unit.

[0012] In one embodiment, the pull-up unit includes a pull-up resistor.

[0013] In one embodiment, the signal output unit further includes a first resistor, the first end of which is connected to the first end of the second current limiting unit, or the first end of the first resistor is connected to the second end of the second current limiting unit; the second end of the first resistor is grounded.

[0014] In one embodiment, the grounding unit includes a second diode, a second switching transistor, and a capacitor; the anode of the second diode is the first terminal of the grounding unit, the cathode of the second diode is connected to the first pin of the second switching transistor, the second pin of the second switching transistor is the second terminal of the grounding unit, and the third pin of the second switching transistor is the third terminal of the grounding unit; the first terminal of the capacitor is connected to the first pin of the second switching transistor, and the second terminal of the capacitor is grounded.

[0015] In one embodiment, the grounding unit further includes a third current limiting unit, and the cathode of the second diode is connected to the first pin of the second switching transistor through the third current limiting unit.

[0016] In one embodiment, the third current limiting unit includes a third current limiting resistor.

[0017] In one embodiment, the grounding unit further includes a second resistor, the first end of which is connected to the first pin of the second switching transistor, and the second end of which is grounded.

[0018] Secondly, this application provides an alarm device, including the aforementioned sound-generating component detection circuit.

[0019] In one embodiment, the alarm further includes an indicator module connected to the main control module.

[0020] In one embodiment, the alarm further includes a drive module for driving the sound-emitting component to operate; the drive module is connected to the sound-emitting component and the main control module; or, the alarm further includes a control module, the drive module being connected to the sound-emitting component and the control module.

[0021] Thirdly, this application provides a fire alarm system, including multiple alarms as described above, wherein the multiple alarms are interconnected and communicate with each other.

[0022] Fourthly, this application provides a method for detecting a sound-generating component, the method comprising: The main control module sends out pulse signals; The main control module receives the feedback signal output by the detection module based on the pulse signal; The main control module determines whether the sound-generating component has malfunctioned based on the feedback signal.

[0023] In one embodiment, the pulse signal is a pulse level signal, which includes at least a high-level state period and a low-level state period, with the low-level state period following the high-level state period; The main control module determines whether the sound-generating component has malfunctioned based on feedback signals, including: The main control module determines whether the sound-generating component has malfunctioned based on the level changes of the feedback signal during the low-level state of the pulse signal.

[0024] In one embodiment, the main control module determines whether a sound-generating component has malfunctioned based on the level change of the feedback signal during the low-level state of the pulse signal, including: The main control module determines whether the sound-generating component has malfunctioned based on the preset time points during the low-level state of the pulse signal and the feedback signal level value.

[0025] In one embodiment, during the high-level state, the feedback signal presents a first level value; The main control module determines whether the sound-generating component has malfunctioned based on the level changes of the feedback signal during the low-level state of the pulse signal, including: The main control module determines whether the sound-generating component has malfunctioned based on the duration of the first level value before the feedback signal changes from the first level value to the second level value during the low-level state of the pulse signal; the first level value and the second level value are different.

[0026] In one embodiment, the main control module determines whether a sound-generating component has malfunctioned based on the duration of the first level value before the feedback signal changes from a first level value to a second level value during the low-level state of the pulse signal, including: The main control module compares the duration with the first preset duration and determines whether the sound-generating component has malfunctioned based on the comparison result.

[0027] In one embodiment, the sound-generating component detection method further includes: When the duration is not less than the first preset duration, the main control module compares the duration with the second preset duration and determines whether the sound-generating component has experienced a performance failure based on the comparison result; wherein the second preset duration is longer than the first preset duration.

[0028] In one embodiment, the main control module determines whether a sound-generating component has malfunctioned based on the level change of the feedback signal during the low-level state of the pulse signal, including: The main control module determines whether the sound-generating component has malfunctioned based on the sequence of level values ​​formed by the level values ​​of the feedback signal at multiple detection time points during the low-level state of the pulse signal.

[0029] In one embodiment, the main control module determines whether a malfunction has occurred in the sound-generating component based on a sequence of level values ​​formed by the level values ​​of the feedback signal at multiple detection time points during the low-level state of the pulse signal, including: The main control module compares the level value sequence with the preset standard sequence and determines whether the sound-generating component has malfunctioned based on the comparison result.

[0030] The advantages of this application compared to the prior art are: This application provides a sound-generating component detection circuit, which includes a main control module, a detection module, and a sound-generating component. The detection module is connected to both the main control module and the sound-generating component. When detecting the sound-generating component, the detection module receives a pulse signal from the main control module and then outputs the pulse signal to the sound-generating component. If the sound-generating component is not faulty, it will charge and store electrical energy upon receiving the pulse signal, and then release the energy. When the sound-generating component releases electrical energy, the detection module will output a feedback signal to the main control module. If the sound-generating component is faulty, it will not charge or discharge upon receiving the pulse signal, and the detection module will directly output another feedback signal to the main control module. The main control module can determine whether the sound-generating component is faulty based on the received feedback signal. Therefore, this application provides a sound-generating component fault detection method that differs from existing technologies. In this method, no drive module is needed to drive the sound-generating component, thus avoiding changes to the original normal operating circuit of the sound-generating component. Furthermore, the detection circuit has a simple structure. Since the sound-generating component only emits a slight sound or even no sound during the detection process, environmental noise is reduced, resulting in a better testing experience. Attached Figure Description

[0031] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This application illustrates a detection circuit for a sound-generating component. Figure 1 ; Figure 2 This is a schematic diagram showing the connection between the sound-generating component detection circuit, the drive module, and the indicator module as illustrated in this application. Figure 3 This application illustrates a detection circuit for a sound-generating component. Figure 2 ; Figure 4 This application illustrates a detection circuit for a sound-generating component. Figure 3 ; Figure 5 This application illustrates a detection circuit for a sound-generating component. Figure 4 ; Figure 6 (a) is a schematic diagram of the pulse signal shown in this application; Figure 6 (b) is a schematic diagram of the feedback signal output by the signal output unit when the sound-generating component is not faulty, as shown in this application; Figure 6(c) is a schematic diagram of the feedback signal output by the signal output unit when the sound-generating component malfunctions as shown in this application; Figure 7 This is a schematic diagram of the pulse signal and feedback signal shown in this application; Figure 8 This application illustrates a detection circuit for a sound-generating component. Figure 5 ; Figure 9 This application illustrates a detection circuit for a sound-generating component. Figure 6 ; Figure 10 This application illustrates a detection circuit for a sound-generating component. Figure 7 ; Figure 11 This application illustrates a detection circuit for a sound-generating component. Figure 8 ; Figure 12 This is a schematic flowchart of the sound-generating component testing method shown in this application.

[0033] Figure label: 1-Sound-generating component detection circuit; 100-Main control module; 200-Detection module; 210-Charging unit; 220-Signal output unit; 230-Grounding unit; 300-Sound-generating component; 400-Indicator module; 500-Power supply module; 600-Drive module. Detailed Implementation

[0034] The terms “first,” “second,” “third,” etc., are used only for distinguishing descriptions and do not indicate a sequence number, nor should they be interpreted as indicating or implying relative importance.

[0035] In the description of this application, it should be noted that the terms "inner", "outer", "left", "right", "upper", "lower", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0036] In the description of this application, unless otherwise expressly specified and limited, the terms “set up,” “install,” “connect,” and “link” shall be interpreted broadly, for example, as a fixed connection, a detachable connection, or an integral connection; as a mechanical connection or an electrical connection; as a direct connection or an indirect connection through an intermediate medium; or as a connection within two components.

[0037] The technical solution of this application will now be clearly and completely described with reference to the accompanying drawings.

[0038] Example 1: Please refer to Figure 1 This is a schematic diagram of the sound-generating component detection circuit 1 shown in this embodiment. Figure 1 As shown, the sound-generating component detection circuit 1 includes a main control module 100, a detection module 200, and a sound-generating component 300. The signal input terminal of the detection module 200 is connected to the main control module 100, the charging / discharging terminal of the detection module 200 is connected to the sound-generating component 300, and the signal output terminal of the detection module 200 is connected to the main control module 100. Specifically, the sound-generating component 300 in this embodiment can be a capacitive sound-generating component, such as a piezoelectric buzzer.

[0039] When detecting a fault in the sound-generating component 300, the main control module 100 sends a pulse signal. The signal input terminal of the detection module 200 receives this pulse signal and sends it to the sound-generating component 300 via the charging / discharging terminal. When the sound-generating component 300 is not faulty, it will charge and store electrical energy upon receiving the pulse signal, and then release the energy after the pulse signal. When the sound-generating component 300 releases electrical energy, the signal output terminal of the detection module 200 will output a feedback signal to the main control module 100. When the sound-generating component 300 is faulty, i.e., it is in a short-circuit or open-circuit fault state, it will not charge upon receiving the pulse signal and will not discharge after the pulse signal. The signal output terminal of the detection module 200 will output another feedback signal to the main control module 100 after the pulse signal. The main control module 100 determines whether the sound-generating component 300 is faulty based on the feedback signal output by the detection module 200. Specifically, after the pulse signal: if the sound-generating component 300 is faulty, the detection module 200 will output a first feedback signal to the main control module 100; if the sound-generating component 300 is not faulty, the detection module 200 will output a second feedback signal to the main control module 100; wherein, the first feedback signal and the second feedback signal have different distinguishable characteristics.

[0040] For example, the pulse signal is a pulse level signal, the first feedback signal is a first level value, and the second feedback signal is a second level value. The first level value is high, and the second level value is low. The pulse signal includes a high-level state period and a low-level state period that are consecutive in time. The high-level state period refers to the time interval from the rising edge of the pulse signal to the falling edge. The low-level state period refers to the time after the falling edge of the pulse signal.

[0041] The pulse signal mentioned above refers to the low-level state period. During this period, the main control module 100 is in a low-level state. By determining whether the detection module 200 outputs a first level value or a second level value, it can be determined whether the sound-generating component 300 has malfunctioned. The main control module 100 may include a high / low level detection circuit, which is entirely composed of hardware such as resistors and capacitors. This circuit determines whether the detection module 200 outputs a first level value or a second level value when the pulse signal is in a low-level state.

[0042] More specifically, during the period when the pulse signal is at a high level, regardless of whether the sound-generating component 300 is faulty, the detection module 200 outputs the same level value to the main control module 100.

[0043] This embodiment provides a fault detection method for the sound-generating component 300 that differs from the prior art. In this detection method, the driving module 600 is not required to drive the sound-generating component 300 to operate, and there is no need to change the original normal operating circuit of the sound-generating component 300. Moreover, the structure of this detection circuit is simpler.

[0044] In addition, there are several possibilities regarding whether the sound-generating component 300 will emit sound during the testing process. If the sound-generating component 300 is in a short-circuit or open-circuit fault state, the sound-generating component 300 will not emit sound.

[0045] If the sound-emitting component 300 is in normal condition, it will only emit a slight sound or even remain silent. Specifically, if the pulse signal emitted by the main control module 100 is lower than the minimum drive level of the sound-emitting component 300, the sound-emitting component 300 cannot be driven to emit sound, but it will still be charged; if the high level of the pulse signal reaches the minimum drive level of the sound-emitting component 300, the sound-emitting component 300 will be driven to emit a short, slight sound. In one embodiment, the pulse signal emitted by the main control module 100 has only one high level, emitting only a short, slight sound during the detection process. Therefore, the solution of this application has the advantage of lower environmental noise during the detection of the sound-emitting component 300, thus providing a better testing experience for the user.

[0046] In addition, in this embodiment, the capacitive characteristics of the sound-generating component 300, namely the charging and discharging characteristics of the sound-generating component 300, are used to realize the fault detection of the sound-generating component 300, and the detection method is simple and convenient.

[0047] Example 2: Based on Example 1, such as Figure 2As shown, this embodiment also includes an indicator module 400, which is not included in the sound-generating component detection circuit 1 but can be located in the alarm. The indicator module 400 is connected to the main control module 100. The main control module 100 can output corresponding detection results through the indicator module 400, and the user can know whether the sound-generating component 300 has malfunctioned based on the output results of the indicator module 400.

[0048] For example, the indicator module 400 may include an indicator light, which can control the indicator light to display green if the sound-emitting component 300 is in a normal state, and control the indicator light to display red if the sound-emitting component 300 is in a fault state. For example, the indicator module 400 may include a voice module, which broadcasts the detection results of the sound-emitting component 300 through voice.

[0049] Optional, such as Figure 2 As shown, in this embodiment, the sound-emitting component 300 can also be connected to a drive module 600. This drive module 600 is not used during the detection process, but rather when driving the sound-emitting component 300 to operate normally. This drive module 600 is not included in the sound-emitting component detection circuit 1 and can also be located within the alarm. In one specific implementation, the drive module 600 is connected to the main control module 100. When the main control module 100 sends a control signal to the drive module 600, the drive module 600 can drive the sound-emitting component 300 to operate and emit a sound. In another specific implementation, the drive module 600 is connected to a control module. When the control module sends a control signal to the drive module 600, the drive module 600 can drive the sound-emitting component 300 to operate and emit a sound.

[0050] Example 3: Based on Example 1, such as Figure 3 As shown, in the sound-generating component detection circuit 1 of this embodiment, the detection module 200 includes a charging unit 210 and a signal output unit 220. The input terminal of the charging unit 210 is the signal input terminal of the detection module 200, and this input terminal is connected to the main control module 100. The output terminal of the charging unit 210 is the charging and discharging terminal of the detection module 200, and this output terminal is connected to the sound-generating component 300. The input terminal of the signal output unit 220 is connected to the output terminal of the charging unit 210. The output terminal of the signal output unit 220 is the signal output terminal of the detection module 200, and this output terminal is connected to the main control module 100.

[0051] In this embodiment, when the sound-generating component 300 is fault detected, the main control module 100 sends a pulse signal, the input terminal of the charging unit 210 receives the pulse signal, and the output terminal of the charging unit 210 outputs the pulse signal to the sound-generating component 300.

[0052] In the specific implementation of this embodiment, while the output terminal of the charging unit 210 outputs the pulse signal to the sound-generating component 300, the output terminal of the charging unit 210 also outputs the pulse signal to the input terminal of the signal output unit 220.

[0053] If the sound-generating component 300 is not faulty, it will charge and store electrical energy upon receiving the pulse signal. During fault detection of the sound-generating component 300, the output of the charging unit 210 can be connected to one port of the sound-generating component 300, while the other port of the sound-generating component 300 is grounded. When the sound-generating component 300 is grounded, the sound-generating component 300 and the signal output unit 220 form a discharge circuit, through which the sound-generating component 300 can discharge.

[0054] Specifically, the pulse signal is a pulse level signal. When the pulse signal is in a low level state, the signal output unit 220 will output different level values ​​depending on whether the sound-generating component 300 is in a normal state or a fault state.

[0055] In another specific embodiment, the pulse signal is a square wave, and a fault detection cycle is formed by a high-level state period and a low-level state period that are consecutive in time. In this embodiment, during the low-level state of the square wave, the signal output unit 220 will output different level values ​​depending on whether the sound-emitting component 300 is in a normal state or a fault state.

[0056] Example 4: Based on Example 3, such as Figure 4 As shown, in this embodiment, the charging unit 210 includes a first diode D1. The anode of the first diode D1 is the input terminal of the charging unit 210 and is connected to pin c of the main control module 100. The cathode of the first diode D1 is the output terminal of the charging unit 210 and is connected to the first terminal a of the sound-emitting component 300. The second terminal b of the sound-emitting component 300 is grounded. Obviously, other unidirectional conductive devices or circuits can be used to replace the first diode D1 to achieve the function of unidirectional conductivity.

[0057] The signal output unit 220 includes a first switch Q1, a second current limiting unit, and a pull-up unit. The first terminal of the second current limiting unit is the input terminal of the signal output unit 220, and this first terminal is connected to the output terminal of the charging unit 210. The second terminal of the second current limiting unit is connected to the first pin of the first switch Q1. The second pin of the first switch Q1 is the output terminal of the signal output unit 220, and this second pin is connected to pin d of the main control module 100, and this second pin is connected to the pull-up unit; the third pin of the first switch Q1 is grounded.

[0058] The first switching transistor Q1 can be a transistor, field-effect transistor, IGBT, or other switching transistor with three pins. Specifically, the first, second, and third pins of the first switching transistor Q1 correspond to the three pins of the transistor, field-effect transistor, IGBT, or other switching transistors, respectively.

[0059] The second current-limiting unit may include components and combinations thereof that have a current-limiting function, such as current-limiting resistors and current-limiting inductors. Specifically, for example... Figure 4 As shown, when the second current limiting unit includes a second current limiting resistor R2, the first end of the second current limiting resistor R2 is the input terminal of the signal output unit 220, and this first end is connected to the output terminal of the charging unit 210. The second end of the second current limiting resistor R2 is connected to the first pin of the first switching transistor Q1.

[0060] A pull-up unit refers to a device or circuit that can pull a signal line potential high to a logic high level. In one implementation, such as... Figure 4 As shown, when the pull-up unit is a pull-up resistor R5, the second pin of the first switching transistor Q1 is the output terminal of the signal output unit 220. This second pin is connected to the pull-up resistor R5 and is connected to the power module 500 through the pull-up resistor R5. This second pin is also connected to pin d of the main control module 100. Specifically, when the first switching transistor Q1 is turned on, the voltage at its second pin is pulled down to near ground potential, and a low level is output to the main control module 100 through the second pin. When the first switching transistor Q1 is turned off, the pull-up resistor R5 pulls the voltage at the second pin up to the external power supply voltage VCC provided by the power module 500, and a high level is output to the main control module 100 through the second pin. Obviously, the high and low level recognition thresholds in the main control module 100 can be configured as follows: when the voltage of the input pin d of the signal output unit 220 is higher than the first preset threshold (e.g., 70% of the external power supply voltage VCC), it is recognized as a logic high level (e.g., '1'); when the voltage of the input pin d of the signal output unit 220 is lower than the second preset threshold (e.g., 30% of the external power supply voltage VCC), it is recognized as a logic low level (e.g., '0').

[0061] In another implementation, the pull-up unit is built into the main control module 100, and the pull-up feedback level is achieved through the main control module 100. Specifically, the pull-up level can be implemented using an integrated circuit within the main control module 100, or by utilizing a pull-up resistor within the integrated circuit; for example... Figure 5As shown, the second pin of the first switching transistor Q1 is connected to pin d of the main control module 100, and the main control module 100 pulls up the voltage. This second pin is also the output terminal of the signal output unit 220. Specifically, when the first switching transistor Q1 is turned on, it pulls the pin voltage of the main control module 100 down to near ground potential VSS, and the main control module 100 reads a low level. When the first switching transistor Q1 is turned off, the internal pull-up resistor of the main control module 100 pulls the pin voltage up to its core power supply voltage VDD, and the main control module 100 reads a high level. Obviously, the high and low level recognition threshold of the main control module 100 can also be configured as follows: when the voltage read by the main control module 100 is higher than a third preset threshold (e.g., 80% of the core power supply voltage VDD), it is recognized as a logic high level (e.g., '1'); when the voltage read by the main control module 100 is lower than a fourth preset threshold (e.g., 20% of the core power supply voltage VDD), it is recognized as a logic low level (e.g., '0').

[0062] like Figure 4 As shown, in this embodiment, the first switching transistor Q1 is a transistor, the second current limiting unit is a second current limiting resistor R2, and the pull-up unit is an independent pull-up resistor R5. The first terminal of the second current limiting resistor R2 is the input terminal of the signal output unit 220, and this first terminal is connected to the output terminal of the charging unit 210. The second terminal of the second current limiting resistor R2 is connected to the base of the transistor. The collector of the transistor is the output terminal of the signal output unit 220, and this collector is connected to pin d of the main control module 100, and this collector is connected to the power supply module 500 through the pull-up resistor R5; the emitter of the transistor is grounded.

[0063] In this embodiment, the function of the second current-limiting resistor R2 is to limit the current, specifically during the charging or discharging process of the sound-generating component 300; wherein, during the discharging process of the sound-generating component 300, it can prevent the first switching transistor Q1 from being broken down, thus protecting the first switching transistor Q1.

[0064] In this embodiment, Figure 6 It contains 3 images, namely Figure 6 (a), 6 (b) and Figure 6 (c) The main control module 100 sends a pulse signal to the detection module 200 through pin c, such as... Figure 6 (a) and Figure 7As shown, the pulse signal is a pulse level signal h1, and contains only one high-level pulse. The first diode D1 receives the pulse signal and outputs it to the sound-generating component 300 and the signal output unit 220. Under the action of the pull-up resistor R5, when the first switch Q1 is in the off state, the output terminal of the signal output unit 220 continuously outputs a high level to pin d. When the signal output unit 220 receives the pulse signal and during the high-level state of the pulse signal, the pulse signal is coupled to the first switch Q1 through the second current-limiting resistor R2, and turns on the first switch Q1; after the first switch Q1 is turned on, the output terminal of the signal output unit 220 outputs a low level to pin d.

[0065] If there is no open circuit fault at either the first terminal a or the second terminal b of the sound-generating component 300, and there is no short circuit fault between the first terminal a and the second terminal b, then the sound-generating component 300 will charge and store electrical energy during the high-level state of the pulse signal.

[0066] In this embodiment, the second terminal b of the sound-generating component 300 is always grounded. The sound-generating component 300 and the signal output unit 220 form a discharge circuit, through which the sound-generating component 300 discharges. The release of the electrical energy stored in the sound-generating component 300 causes the output terminal of the signal output unit 220 to continue outputting a low level for a period of time after the high-level state of the pulse signal.

[0067] Specifically, during the low-level state of the pulse signal, the sound-generating component 300 discharges. While the sound-generating component 300 is discharging, the first switching transistor Q1 is continuously turned on, and the signal output unit 220 continuously outputs a low level to pin d. As the discharge of the sound-generating component 300 ends, the first switching transistor Q1 gradually changes from the on state to the off state. Therefore, the level output by the signal output unit 220, under the action of the pull-up resistor R5, gradually rises from a low level to a high level. Figure 6 As shown in (b), this is a schematic diagram of the signal output level of the signal output unit 220 when the sound-generating component 300 does not have a short-circuit fault or an open-circuit fault. Figure 6 (b) and Figure 7As shown, when there is no short circuit or open circuit fault in the sound-generating component 300, the feedback signal output by the signal output unit 220 is h2. In the feedback signal h2, the level value output by the signal output unit 220 is divided into four stages according to the timing sequence: In the first stage, before the pulse signal is input, the output level value of the signal output unit 220 is maintained at a high level; In the second stage, during the high level state of the pulse signal, the output level value of the signal output unit 220 jumps to a low level; In the third stage, during the low level state after the high level state of the pulse signal, the output level value of the signal output unit 220 first continues to maintain a low level for a certain period of time, and then gradually rises to a high level; In the fourth stage, since the pulse signal is continuously in a low level state or after the pulse signal ends, the output level value of the signal output unit 220 will continue to maintain the high level, and the high level value is equal to or basically equal to the high level value output in the first stage.

[0068] If the first terminal a and / or the second terminal b of the sound-generating component 300 are open-circuited, or if the first terminal a and the second terminal b of the sound-generating component 300 are short-circuited, the sound-generating component 300 will not discharge after the pulse signal reaches a high level. Therefore, at the falling edge of the pulse signal, the low level output by the signal output unit 220 will transition back to a high level. Figure 6 As shown in (c), this is a schematic diagram of the signal output level of the signal output unit 220 when the sound-generating component 300 has a short circuit and / or open circuit fault. Figure 6 (c) and Figure 7 As shown, when the sound-generating component 300 has a short-circuit fault or an open-circuit fault, the feedback signal output by the signal output unit 220 is h3. In the feedback signal h3, the level value output by the signal output unit 220 is divided into three stages according to the timing sequence: In the first stage, before the pulse signal is input, the output level value of the signal output unit 220 is maintained at a high level; In the second stage, during the high-level state of the pulse signal, the output level value of the signal output unit 220 jumps from a high level to a low level; In the third stage, during the continuous low-level state after the high-level state of the pulse signal or after the pulse signal ends, the output level value of the signal output unit 220 will jump from a low level to a high level and remain at that high level, and this high level value is equal to or substantially equal to the high level value output in the first stage.

[0069] according to Figure 6 (b) and Figure 6(c) It can be seen that, whether the sound-generating component 300 is faulty or not, during the low-level state after the falling edge of the pulse signal, the signal output unit 220 can feedback different level values ​​or different level changes. Based on this, the main control module 100 can use any one of the following three fault judgment schemes to determine whether the sound-generating component 300 is faulty. The fault judgment schemes are explained below.

[0070] In the first fault diagnosis scheme, the main control module 100 can determine whether the sound-generating component 300 has malfunctioned at a preset time point during the low-level state of the pulse after the falling edge of the pulse signal, based on the high or low level of the output level value of the signal output unit 220. In this scheme, the main control module 100 can detect the output level of the signal output unit 220 at a preset time point during the low-level state after the falling edge of the pulse signal, and determine whether the sound-generating component 300 has malfunctioned based on whether the signal output unit 220 outputs a high level or a low level. Specifically, the main control module 100 determines whether the output level of the signal output unit 220 is high or low based on a preset high / low level identification threshold. If the signal output unit 220 outputs a low level at the preset time point, the sound-generating component 300 does not have a short circuit or open circuit fault and is in a normal state; if the signal output unit 220 outputs a high level at the preset time point, the sound-generating component 300 has a short circuit and / or open circuit fault.

[0071] like Figure 7 As shown, in one embodiment, the preset time point is 50 milliseconds after the falling edge of the pulse signal. At this preset time point, the main control module 100 determines whether the level value output by the signal output unit 220 is high or low based on a preset high / low level identification threshold: if it is identified as high, it is determined that the sound-generating component 300 has a functional fault, such as an open circuit and / or short circuit fault; if it is identified as low, it is determined that the sound-generating component 300 is in a normal state.

[0072] In one specific embodiment, such as Figure 7As shown, the low-level state after the falling edge of the pulse signal can have three time periods, as enclosed by dashed boxes f1, f2, and f3. The preset time point can be located within the time periods of dashed boxes f1 and f2. Furthermore, w1 is the high / low level identification threshold. Within the time periods of dashed boxes f1 and f2, the level of feedback signal h2 is below w1 (low level), and the level of feedback signal h3 is above w2 (high level). Therefore, within these two time periods, feedback signals h2 and h3 output different level values. By selecting the preset time point within these two time periods, it is possible to accurately determine whether the sound-generating component 300 has malfunctioned. Additionally, this preset time point can be set based on the test data from the sound-generating component detection circuit 1.

[0073] In the second fault diagnosis scheme, the main control module 100 can determine whether the sound-generating component 300 has malfunctioned based on the duration of the signal output unit 220 resuming its output of a specified level value during the low-level state following the falling edge of the pulse signal. The main control module 100 determines whether the level value output by the signal output unit 220 is high or low based on a preset high / low level identification threshold. In one specific implementation, this duration is determined by the time between the falling edge of the pulse signal and the moment the signal output unit 220 resumes its high-level output.

[0074] In one implementation, the main control module 100 can detect the duration of the low-level signal output by the signal output unit 220 during the low-level state after the falling edge of the pulse signal, and determine whether the sound-emitting component 300 has malfunctioned based on the detection result. Specifically, a first preset duration can be preset, and the main control module 100 compares the duration with the first preset duration to determine the state of the sound-emitting component 300. In one embodiment, the main control module 100 has a preset level detection period. When a feedback signal is detected to be high at a certain detection moment, if the detection period at that detection moment is T1 and the total duration of one or more detection periods before that detection moment is T2, then the duration of the low level is the sum of the duration T1 and the total duration T2; where T2 is an integer multiple of T1. In another embodiment, the duration of the low level can be only the total duration T2; because the moment when the feedback signal becomes high may be before the detection moment, i.e., within the detection period before that detection moment; thus, the duration obtained in this embodiment excludes the duration when the feedback signal is not low.

[0075] Obviously, if the pulse signal contains multiple high levels, since level detection needs to be performed during the falling edge after each high level, the duration of the pulse low level state after the falling edge needs to be adapted to the first preset duration, that is, it cannot be less than the first preset duration; in addition, the level detection period is less than the duration of the pulse low level state, and the two need to be adapted to ensure that one or more level detections are completed.

[0076] In one embodiment, during the low-level state after the falling edge of the pulse signal, the level detection period is 10 milliseconds. The main control module 100 detects once every 10 milliseconds until it detects that the level value output by the signal output unit 220 has recovered to a high level, and the first preset duration is 80 milliseconds. If the duration of the low level output by the signal output unit 220 is greater than 80 milliseconds, that is, the duration between the falling edge of the pulse signal and the moment when the signal output unit 220 outputs a high level is greater than 80 milliseconds (e.g., '90 milliseconds', '100 milliseconds', etc.), then it is determined that the sound-emitting component 300 is in a normal state. If the duration of the low level output by the signal output unit 220 is equal to 10 milliseconds, that is, the high level output by the signal output unit 220 is detected in the first 10 milliseconds after the falling edge of the pulse signal, then it is determined that the sound-emitting component 300 has an open circuit and / or short circuit fault.

[0077] In another embodiment, the sound-generating component 300 is a piezoelectric buzzer. When the buzzer plate of the piezoelectric buzzer has a performance fault that leads to a reduction in capacitance, such as cracking, the discharge time of the sound-generating component 300 will be shortened. During the low-level state after the falling edge of the pulse signal, the duration of the low-level output by the signal output unit 220 will also be shortened. When the sound-generating component 300 exhibits this performance fault, there is a risk that the expected decibel value may not be achieved when the sound-generating component 300 is working normally. This fault judgment scheme can determine whether the sound-generating component 300 has a performance fault such as a cracked buzzer plate based on the duration of the low-level output by the signal output unit 220. In implementation, during the low-level state after the falling edge of the pulse signal, the duration of the low-level output by the signal output unit 220 is compared with a second preset duration. If it is less than the second preset duration, it is determined that such a performance fault exists; if it is not less than the second preset duration, it is determined that such a performance fault does not exist. Specifically, taking a 10-millisecond detection period as an example, the first preset duration can be set to 80 milliseconds and the second preset duration can be set to 100 milliseconds. If the duration of the low-level output by the signal output unit 220 is greater than 80 milliseconds and not less than 100 milliseconds (e.g., a duration of 100 milliseconds), it is determined that the sound-emitting component 300 does not have a functional or performance fault. If the duration of the low-level output by the signal output unit 220 is greater than 80 milliseconds but less than 100 milliseconds (e.g., a duration of 90 milliseconds), it is determined that the sound-emitting component 300 does not have a functional fault but does have a performance fault. Similarly, if the pulse signal contains multiple high levels, this type of performance fault is determined after the falling edge of the pulse signal. Since the second preset duration is not less than the first preset duration, the duration of the low-level pulse state after the falling edge needs to be adapted to the second preset duration, i.e., it cannot be less than the second preset duration. In addition, the first preset duration and / or the second preset duration can be confirmed in advance through experimental testing and preset in the main control module 100.

[0078] The third fault diagnosis scheme is that the main control module 100 can determine whether the sound-generating component 300 has malfunctioned during the low-level state of the pulse after the falling edge of the pulse signal, at multiple preset detection time points, based on the high and low sorting of the output level values ​​of the signal output unit 220. In this scheme, the main control module 100 can detect the level value output by the signal output unit 220 and confirm the corresponding logic value (e.g., '1' or '0') at multiple preset detection time points during the low-level state after the falling edge of the pulse signal. Therefore, based on the high-low order of the level values ​​output by the signal output unit 220, i.e., the order of the logic values, it can determine whether the sound-generating component 300 has malfunctioned. Specifically, the main control module 100 determines whether the level value output by the signal output unit 220 is high or low based on a preset high / low level identification threshold. The high / low order of the level values ​​is determined by the order of the detection time.

[0079] In one embodiment, two detection time points are preset. The fault condition of the sound-generating component 300 can be determined based on the confirmed logical value sorting: if the logical value sorting is '00' or '01', then the sound-generating component 300 does not have a short circuit or open circuit functional fault and is in a normal state; if the logical value sorting is '11', then the sound-generating component 300 has a short circuit and / or open circuit functional fault. Obviously, the first detection time point can be confirmed in advance through experimental testing and preset in the main control module 100.

[0080] In another embodiment, three or more detection time points are preset. The functional fault condition of the sound-generating component 300 can be determined based on the first two values ​​of the confirmed logical value ranking. Furthermore, after determining that the sound-generating component 300 does not have short-circuit or open-circuit functional faults, the logical value ranking can be used to further determine whether the sound-generating component 300 has a performance fault. For example, if the sound-generating component 300 is a piezoelectric buzzer, a performance fault refers to a fault such as cracking of the buzzer plate that leads to a reduction in capacitance. Additionally, regarding performance fault identification, a standard sequence can be preset; the main control module 100 determines whether the sound-generating component 300 has a performance fault by comparing the logical value ranking with the standard ranking.

[0081] In one specific embodiment for further determining whether the sound-generating component 300 has a performance fault, eight preset detection time points are used, and the preset standard sorting includes five or more low-level logic values ​​'0'. The main control module 100 has a detection cycle of 10 milliseconds and performs eight detections in total. During the low-level state of the pulse signal after the falling edge, the main control module 100 completes eight detections and stores eight consecutive logic values ​​after 80 milliseconds, thus forming a logic value sorting. Then, the main control module 100 compares the logic value sorting with the standard sorting to determine whether the sound-generating component 300 has a performance fault: if the logic value sorting includes five or more low-level logic values ​​'0', the sound-generating component 300 is determined not to have a performance fault; otherwise, a performance fault is determined to exist. For example, if the logic value sorting output and stored by the signal output unit 220 is '00000111' or '00000011', then the sound-generating component 300 is determined not to have a performance fault. For example, if the logical values ​​output and stored by the signal output unit 220 are sorted as '00001111' or '00011111', then it is determined that the sound-generating component 300 has a performance failure.

[0082] In these fault diagnosis schemes, if the pulse signal contains only one high level, then the period following the high level refers to the low level period after the pulse signal ends, i.e., after the pulse signal ends, to determine whether the sound-generating component 300 has malfunctioned. In one embodiment, the pulse signal is a square wave with only one high level.

[0083] In other fault diagnosis schemes for the sound-generating component 300, the pulse signal may also contain two high levels, three high levels, or even more. Fault diagnosis can be performed multiple times during the low-level period following each high level: if the results of multiple fault diagnosis are consistent, the fault diagnosis of the sound-generating component 300 ends and the diagnosis result is output to the indicator module 400; if the results of multiple fault diagnosis are inconsistent, the abnormal result of the fault diagnosis is fed back to the main control module 100 and / or fed back to the indicator module 400.

[0084] Example 5: The difference from Embodiment 4 is that in this embodiment, the charging unit 210 includes a first diode D1 and a first current limiting unit. In one implementation, the anode of the first diode D1 is the input terminal of the charging unit 210, which is connected to pin c of the main control module 100. The cathode of the first diode D1 is connected to the first terminal of the first current limiting unit, and the second terminal of the first current limiting unit is the output terminal of the charging unit 210, which is connected to the first terminal a of the sound-generating component 300.

[0085] In another implementation, the first end of the first current limiting unit is the input end of the charging unit 210, the second end of the first current limiting unit is connected to the anode of the first diode D1, and the cathode of the first diode is the output end of the charging unit 210.

[0086] Optional, such as Figure 8 As shown, the first current limiting unit includes a first current limiting resistor R1, the first end of the first current limiting resistor is the first end of the first current limiting unit, and the second end of the first current limiting resistor is the second end of the first current limiting unit.

[0087] Obviously, the first current-limiting resistor R1 and the second current-limiting resistor R2 serve the same purpose. Therefore, the first current-limiting resistor R1 can be replaced by other current-limiting units, which may include current-limiting resistors, current-limiting inductors, and other components and combinations thereof that have current-limiting functions.

[0088] In this embodiment, the first current-limiting resistor R1 can limit the current to prevent excessive current from damaging the sound-generating component 300 when charging it.

[0089] Example 6: The difference from Embodiment 4 above is that, as Figure 8 As shown, in this embodiment, the signal output unit 220 further includes a first resistor R1'. The first end of the first resistor R1' is connected to the first end of the second current-limiting unit, or the first end of the first resistor R1' is connected to the second end of the second current-limiting unit. Additionally, the second end of the first resistor R1' is grounded.

[0090] In this embodiment, by setting the first resistor R1', the discharge speed of the sound-generating component 300 is accelerated, which can improve the fault detection efficiency in some fault judgment schemes. For example, in the second fault judgment scheme, accelerating the discharge speed of the sound-generating component 300 can shorten the time it takes for the signal output unit 220 to return to the high output level when the sound-generating component 300 is in a normal state, thereby enabling a faster fault detection conclusion.

[0091] Example 7: The difference from Example 6 is that, as Figure 9 As shown, in this embodiment, the detection module 200 also has a grounding terminal, and the second terminal b of the sound-emitting component 300 is grounded after being connected to the detection module 200. Specifically, the detection module 200 includes a grounding unit 230, the first terminal of which is connected to the input terminal of the charging unit 210. The second terminal of the grounding unit 230 is the connection terminal of the detection module 200, which is connected to the second terminal b of the sound-emitting component 300, and the third terminal of the grounding unit 230 is grounded.

[0092] In this embodiment, the second terminal b of the sound-generating component 300 is not grounded during non-fault detection periods. Only when fault detection is performed on the sound-generating component 300 is the second terminal b grounded, so that the sound-generating component 300 and the signal output unit 220 form a discharge circuit. Therefore, a grounding unit 230 is added to the detection module 200, which ensures that the second terminal b of the sound-generating component 300 remains grounded only during fault detection periods.

[0093] Specifically, the main control module 100 outputs as follows: Figure 6 During the high-level state of the pulse signal h1 shown in (a), the pulse signal is divided into two paths: one path goes through the input terminal of the charging unit 210 to the charging unit 210; the other path goes through the first terminal of the grounding unit 230 to the grounding unit 230. Under the action of the high-level pulse signal, the grounding unit 230 forms a path, connecting the second terminal b of the sound-generating component 300 to the ground.

[0094] In addition, in this embodiment, when the sound-generating component 300 is not fault-detected, the main control module 100 will not output a pulse signal for fault detection, the grounding unit 230 will not be turned on, and the sound-generating component 300 will not be grounded, which will not affect the normal operation of the sound-generating component 300.

[0095] Example 8: Based on Example 7, such as Figure 10 As shown, in this embodiment, the grounding unit 230 includes a second diode D2, a second switch Q2, and a capacitor C1. The anode of the second diode D2 is the first terminal of the grounding unit 230, which is connected to the input terminal of the charging unit 210. The cathode of the second diode D2 is connected to the first pin of the second switch Q2. The second pin of the second switch Q2 is the second terminal (connection terminal) of the grounding unit 230, which is connected to the second terminal b of the sound-generating component 300. The third pin of the second switch Q2 is the third terminal (grounding terminal) of the grounding unit 230, and this third terminal is grounded. The first terminal of the capacitor C1 is connected to the first pin of the second switch Q2, and the second terminal of the capacitor C1 is grounded.

[0096] In this embodiment, the grounding unit 230 receives a pulse signal sent by the main control module 100. This pulse signal is coupled to the second switch Q2 via the second diode D2. During the high-level state of the pulse signal, the second switch Q2 is turned on. After the second switch Q2 is turned on, the second terminal b of the sound-emitting component 300 is grounded. Additionally, during the high-level state of the pulse signal, capacitor C1 charges first, then the second switch Q2 is turned on, and the sound-emitting component 300 is charged after the second switch Q2 is turned on. During the low-level state of the pulse signal, the charged capacitor C1 discharges, causing the second switch Q2 to continue conducting for a period of time. Thus, during fault detection, capacitor C1 allows the second terminal b of the sound-emitting component 300 to remain grounded. In one specific embodiment, when the voltage across capacitor C1 is charged to a level higher than the turn-on threshold voltage of the second switch Q2 (e.g., approximately 0.6V), the second switch Q2 is turned on.

[0097] Clearly, the second switch Q2 serves the same function as the first switch Q1. Therefore, the second switch Q2 can also be implemented using a transistor, field-effect transistor, IGBT, or other three-pin switching transistor. In one specific implementation, the second switch Q2 is a transistor, in which case the first pin of the second switch Q2 is the base, the second pin is the collector, and the third pin is the emitter.

[0098] Clearly, the second diode D2 and the first diode D1 serve the same function, thus other unidirectional conductive devices or circuits can be used to replace the second diode D2 to achieve unidirectional conductivity.

[0099] Clearly, capacitor C1 performs the function of storing and releasing electrical energy. Therefore, other components or circuits that perform the same function, such as inductors, can be used to replace capacitor C1 to achieve the same effect.

[0100] Example 9: The difference from Embodiment 8 is that in this embodiment, the grounding unit 230 further includes a third current-limiting unit, and the cathode of the second diode D2 is connected to the first pin of the second switching transistor Q2 through the third current-limiting unit. For example, as shown... Figure 11 As shown, the third current limiting unit may include a third current limiting resistor R3.

[0101] Obviously, the third current-limiting resistor R3 and the second current-limiting resistor R2 serve the same purpose. Therefore, the third current-limiting resistor R3 can be replaced by other current-limiting units, which may include current-limiting resistors, current-limiting inductors, and other components and combinations thereof that have current-limiting functions.

[0102] In this embodiment, the function of the third current-limiting resistor R3 is to limit the current when charging capacitor C1, so as to avoid damaging capacitor C1.

[0103] In one implementation, the grounding unit 230 further includes a second resistor R2', the first end of which is connected to the first pin of the second switch Q2, and the second end of which is grounded.

[0104] The function of the second resistor R2' is to accelerate the discharge speed of capacitor C1 and shorten the conduction time of the second switch Q2, which can improve the fault detection efficiency in some fault diagnosis schemes.

[0105] Of course, it is understandable that in practice, there may be only the third current limiting unit, or only the second resistor R2', or both the third current limiting unit and the second resistor R2' may exist simultaneously.

[0106] Example 10: This embodiment provides an alarm device, which includes the sound-emitting component detection circuit 1 of any of the above embodiments. Optionally, the drive module 600 and the indicator module 400 in the above embodiments can also be located in the alarm device; the alarm device may also include a smoke sensor, which detects whether there is smoke in the environment where the alarm device is located. If smoke is detected, it indicates that there may be a fire source in the environment where the alarm device is located. The main control module 100 or other control module controls the sound-emitting component 300 to operate and emit a warning alarm sound to remind people to evacuate in time and protect people's lives and property.

[0107] Optionally, the alarm can also be a carbon monoxide alarm, including a carbon monoxide sensor. Optionally, the alarm can also be a heat alarm, including a heat sensor. Optionally, the alarm can also be a composite alarm, including at least two sensors such as a carbon monoxide sensor, a smoke sensor, and a heat sensor. When the alarm detects that the alarm conditions are met, the main control module 100 or other control modules control the sound-emitting component 300 to emit a warning alarm sound.

[0108] Example 11: This embodiment provides a fire alarm system, which includes multiple alarms as described above. These alarms are interconnected and can communicate their status information with each other. The interconnection of the multiple alarms can be wired and / or wireless. Specifically, the status information of the alarms can be the result information detected by the audible component 300, or the fault information detected by the audible component 300.

[0109] Furthermore, multiple alarms can communicate with each other, sharing alarm information. For example, an office building may be divided into multiple zones, with multiple alarms installed in their respective zones. When a fire occurs in one zone, the corresponding alarm will detect the fire and trigger an alarm, providing an audible and visual warning to alert people in that zone to evacuate. Because of the risk of fire spreading, the multiple alarms can communicate with each other, causing alarms in other zones to also issue audible and visual warnings, ensuring the safety of people within the office building.

[0110] Example 12: like Figure 12 As shown, this embodiment provides a method for detecting a sound-generating component 300. This detection method is applied to the sound-generating component detection circuit 1 of any of the above embodiments. The method for detecting the sound-generating component 300 may include the following steps: Step S1000: The main control module 100 sends out a pulse signal.

[0111] The pulse signal can be a pulse level signal or a square wave signal.

[0112] Step S2000: The main control module 100 receives the feedback signal output by the detection module 200 based on the pulse signal.

[0113] In this step, the detection module 200 receives the pulse signal. Taking a pulse-level signal as an example: if the sound-emitting component 300 is faulty, it will not charge during the high-level state of the pulse signal; it will not discharge during the low-level state of the pulse signal, and the detection module 200 outputs a first feedback signal to the main control module 100. If the sound-emitting component 300 is not faulty, it will charge during the high-level state of the pulse signal; subsequently, it will discharge during the low-level state of the pulse signal, and the detection module 200 outputs a second feedback signal to the main control module 100. The first and second feedback signals have different levels.

[0114] Step S3000: The main control module 100 determines whether the sound-generating component 300 has malfunctioned based on the feedback signal.

[0115] In this step, the main control module 100 can determine whether the sound-generating component 300 has malfunctioned based on the level of the feedback signal sent by the detection module 200 during the low-level state of the pulse signal.

[0116] In one implementation, in step S3000 above, the main control module 100 can determine whether the sound-generating component 300 has malfunctioned based on the level change of the feedback signal sent by the detection module 200 during the low-level state.

[0117] Specifically, when the sound-generating component 300 is functioning correctly, during the low-level state of the pulse signal, the output level of the detection module 200 initially remains low for a certain period, then gradually rises to a high level and remains there. When the sound-generating component 300 is faulty, at the falling edge of the pulse signal, the output level of the detection module 200 jumps to a high level; and during the low-level state of the pulse signal, the detection module 200 continuously outputs a high level. Therefore, during the low-level state of the pulse signal, the level of the feedback signal sent by the detection module 200 is different, thus allowing the determination of whether the sound-generating component 300 is faulty based on the changes in the level of the feedback signal.

[0118] It should be noted that the level change of the aforementioned feedback signal can include the level value of the feedback signal at a preset time point during the low-level state, or it can include a sequence of level values ​​composed of the level values ​​of several detection time points of the feedback signal during the low-level state, or it can detect the total duration of the low level before the feedback signal changes from low to high during the low-level state. By using one or more of the above implementation methods, it is determined whether the sound-emitting component 300 has malfunctioned. Specifically, the level value sequence is the order of the level values ​​from high to low according to the detection time, that is, the order of the logic values.

[0119] The following sections will explain each implementation method: Implementation method 1: The main control module 100 determines whether the sound-generating component 300 has malfunctioned based on the level value of the feedback signal at a preset time point during the low-level state of the pulse signal. For example, the level value 20 milliseconds after the falling edge of the high-level pulse signal: if the level value is low ("0"), it indicates that the sound-generating component 300 is not malfunctioning. If the level value is high ("1"), it indicates that the sound-generating component 300 has malfunctioned.

[0120] Implementation Method Two: The main control module 100 determines whether the sound-generating component 300 has malfunctioned based on the total duration of the first level value before the feedback signal changes from the first level value to the second level value during the low-level state of the pulse signal. Here, the first level value is low, and the second level value is high. This duration reflects the time it takes for the feedback signal to recover to the high level during the low-level state of the pulse signal. This duration can be determined by the total duration of the low level in the feedback signal after the falling edge of the pulse signal.

[0121] The main control module 100 can store a first preset duration. By comparing the duration with this first preset duration, it can be determined whether the sound-generating component 300 has a fault. If the duration is not less than the first preset duration, the sound-generating component 300 does not have a short circuit and / or open circuit fault, that is, there is no functional fault. If the duration is less than the first preset duration, the sound-generating component 300 has a short circuit and / or open circuit fault, that is, there is a functional fault.

[0122] When the sound-generating component 300 is a piezoelectric buzzer, the main control module 100 can also pre-store a second preset duration, which is longer than the first preset duration. When the duration is not less than the first preset duration, the main control module 100 can compare the duration with the second preset duration to determine whether the sound-generating component 300 has a performance fault that could lead to reduced capacitance, such as a cracked buzzer plate. If the comparison result shows that the duration is not less than the second preset duration, it indicates that the sound-generating component 300 does not have a performance fault; if the comparison result shows that the duration is less than the second preset duration, it indicates that the sound-generating component 300 has a performance fault. Obviously, the second preset duration can also be equal to the first preset duration. When the sound-generating component 300 does not have a performance fault, it certainly does not have a functional fault.

[0123] For example, the moment the feedback signal goes high can be detected, and the difference between this moment and the moment corresponding to the falling edge can be calculated. The result is the total duration of the low level output by the feedback signal. For example, during the low level state, the level detection period can be set to 20 milliseconds, and the level value of the feedback signal can be detected every 20 milliseconds. If a high level is detected in the feedback signal in the 5th detection period, then the previous 4 detection periods can be considered as the total duration of the low level, i.e., the total duration is 80 milliseconds.

[0124] The first preset duration is 50 milliseconds, the second preset duration is 70 milliseconds, and the duration of 80 milliseconds is greater than 50 milliseconds, so the sound-emitting component 300 has no functional fault; at the same time, if the duration of 80 milliseconds is also greater than the second preset duration, then there is also no performance fault.

[0125] Implementation method three: The main control module 100 determines the corresponding logic value sequence based on the level value sequence formed by multiple detection time points of the feedback signal during the low-level state of the pulse signal, and determines whether the sound-generating component 300 has a fault based on the logic value sequence. For example, if the logic value sequence formed by the three detection time points of 20 milliseconds, 35 milliseconds, and 40 milliseconds after the falling edge is '000', '001', or '011', then the sound-generating component 300 does not have a short circuit or open circuit functional fault and is in a normal state; if the logic value sequence is '111', then the sound-generating component 300 has a short circuit and / or open circuit functional fault.

[0126] When the sound-generating component 300 is a piezoelectric buzzer, the main control module 100 can also simultaneously determine whether the sound-generating component 300 has a functional fault or a performance fault. For example, the detection time points are 10 milliseconds, 20 milliseconds, 30 milliseconds, 40 milliseconds, 50 milliseconds, 60 milliseconds, 70 milliseconds, 80 milliseconds, 90 milliseconds, and 100 milliseconds after the falling edge, that is, ten detections are performed and ten logic values ​​are stored, forming a logic value sequence according to the detection time. Furthermore, the first three bits of the logic value sequence are used to determine whether the sound-generating component 300 has a functional fault, the specific method of which is the same as above and will not be described again.

[0127] When the sound-generating component 300 is not functionally faulty, the logic value sequence is compared with a preset standard sequence. Based on the comparison result, it is determined whether the sound-generating component 300 has a performance fault. For example, the preset standard sequence can have multiple low-level logic values ​​"0". Taking a logic value sequence containing ten logic values ​​as an example, the preset standard sequence can contain 5, 6, 7, 8, 9, or 10 low-level logic values ​​"0". The logic value sequence is compared with the preset standard sequence one by one. By comparison, it is determined whether the logic value sequence is the same as one of the preset standard sequences. If they are the same, it is determined that the sound-generating component 300 has no performance fault. If the logic value sequence is different from all the preset standard sequences, it is determined that a performance fault exists.

[0128] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A sound-generating component detection circuit, characterized in that, The sound-generating component detection circuit includes: The main control module is used to send pulse signals; The detection module has its signal input terminal connected to the main control module for receiving the pulse signal, and its signal output terminal connected to the main control module for outputting a feedback signal to the main control module. A sound-generating component, wherein the first end of the sound-generating component is connected to the charging and discharging terminal of the detection module, and the second end of the sound-generating component is grounded; The main control module is used to determine whether the sound-generating component has malfunctioned based on the feedback signal.

2. The sound-generating component detection circuit according to claim 1, characterized in that, The detection module includes: A charging unit, wherein the input terminal of the charging unit is the signal input terminal of the detection module, and the output terminal of the charging unit is the charging and discharging terminal of the detection module; A signal output unit, wherein the input terminal of the signal output unit is connected to the output terminal of the charging unit, and the output terminal of the signal output unit is the signal output terminal of the detection module.

3. The sound-generating component detection circuit according to claim 2, characterized in that, The charging / discharging terminal of the detection module is connected to the first terminal of the sound-generating component, and the connecting terminal of the detection module is connected to the second terminal of the sound-generating component. The detection module also includes: A grounding unit, wherein the first end of the grounding unit is connected to the input end of the charging unit, the second end of the grounding unit is the connection end of the detection module, and the third end of the grounding unit is grounded. The second end of the sound-generating component is grounded through the grounding unit.

4. The sound-generating component detection circuit according to claim 2, characterized in that, The charging unit includes: The first diode has its anode serving as the input terminal of the charging unit and its cathode serving as the output terminal of the charging unit.

5. The sound-generating component detection circuit according to claim 2, characterized in that, The charging unit includes: First diode and first current limiting unit; The anode of the first diode is the input terminal of the charging unit, the cathode of the first diode is connected to the first terminal of the first current limiting unit, and the second terminal of the first current limiting unit is the output terminal of the charging unit. Alternatively, the first end of the first current limiting unit is the input end of the charging unit, the second end of the first current limiting unit is connected to the anode of the first diode, and the cathode of the first diode is the output end of the charging unit.

6. The sound-generating component detection circuit according to claim 5, characterized in that, The first current limiting unit includes a first current limiting resistor, the first end of the first current limiting resistor is the first end of the first current limiting unit, and the second end of the first current limiting resistor is the second end of the first current limiting unit.

7. The sound-generating component detection circuit according to claim 2, characterized in that, The signal output unit includes: The system comprises a first switching transistor, a second current limiting unit, and a pull-up unit. The first terminal of the second current limiting unit is the input terminal of the signal output unit, and the second terminal of the second current limiting unit is connected to the first pin of the first switching transistor. The second pin of the first switching transistor is the output terminal of the signal output unit, and the second pin is connected to the power module through the pull-up unit. The third pin of the first switching transistor is grounded. Alternatively, the signal output unit may include: A first switching transistor and a second current limiting unit, wherein the first end of the second current limiting unit is the input end of the signal output unit, the second end of the second current limiting unit is connected to the first pin of the first switching transistor, the second pin of the first switching transistor is the output end of the signal output unit, and the third pin of the first switching transistor is grounded.

8. The sound-generating component detection circuit according to claim 7, characterized in that, The second current limiting unit includes a second current limiting resistor, the first end of the second current limiting resistor is the first end of the second current limiting unit, and the second end of the second current limiting resistor is the second end of the second current limiting unit.

9. The sound-generating component detection circuit according to claim 7, characterized in that, The pull-up unit includes a pull-up resistor.

10. The sound-generating component detection circuit according to claim 7, characterized in that, The signal output unit further includes: A first resistor, wherein a first end of the first resistor is connected to a first end of the second current limiting unit, or a first end of the first resistor is connected to a second end of the second current limiting unit; The second terminal of the first resistor is grounded.

11. The sound-generating component detection circuit according to claim 3, characterized in that, The grounding unit includes: The second diode and the second switch are described, wherein the anode of the second diode is the first terminal of the grounding unit, the cathode of the second diode is connected to the first pin of the second switch, the second pin of the second switch is the second terminal of the grounding unit, and the third pin of the second switch is the third terminal of the grounding unit. A capacitor, wherein the first end of the capacitor is connected to the first pin of the second switching transistor, and the second end of the capacitor is grounded.

12. The sound-generating component detection circuit according to claim 11, characterized in that, The grounding unit further includes: The third current limiting unit connects the cathode of the second diode to the first pin of the second switching transistor.

13. The sound-generating component detection circuit according to claim 12, characterized in that, The third current limiting unit includes a third current limiting resistor.

14. The sound-generating component detection circuit according to claim 11, characterized in that, The grounding unit further includes: The second resistor has its first end connected to the first pin of the second switching transistor, and its second end grounded.

15. An alarm device, characterized in that, Includes the sound-generating component detection circuit as described in any one of claims 1-14.

16. The alarm device according to claim 15, characterized in that, The alarm also includes: An indicator module is connected to the main control module.

17. The alarm device according to claim 15, characterized in that, The alarm also includes: A drive module is used to drive the sound-generating component to operate; The drive module is connected to the sound-generating component and the main control module; Alternatively, the alarm may also include: The control module is connected to the sound-generating component and the control module.

18. A fire alarm system, characterized in that, The fire alarm system includes: Multiple alarms as described in any one of claims 15-17, wherein the multiple alarms are interconnected.

19. A method for detecting a sound-generating component, characterized in that, The sound-generating component detection method, applied to the sound-generating component detection circuit as described in any one of claims 1-14, comprises: The main control module sends out pulse signals; The main control module receives the feedback signal output by the detection module based on the pulse signal; The main control module determines whether the sound-generating component has malfunctioned based on the feedback signal.

20. The method for detecting a sound-generating component according to claim 19, characterized in that, The pulse signal is a pulse level signal, and the pulse signal includes at least a high level state period and a low level state period, wherein the low level state period is after the high level state period; The main control module determines whether the sound-generating component has malfunctioned based on the feedback signal, including: The main control module determines whether the sound-generating component has malfunctioned based on the level change of the feedback signal during the low-level state of the pulse signal.

21. The method for detecting a sound-generating component according to claim 20, characterized in that, The main control module determines whether the sound-generating component has malfunctioned based on the level change of the feedback signal during the low-level state of the pulse signal, including: The main control module determines whether the sound-generating component has malfunctioned based on a preset time point during the low-level state of the pulse signal and the level value of the feedback signal.

22. The method for detecting a sound-generating component according to claim 20, characterized in that, During the high-level state, the feedback signal presents a first level value; The main control module determines whether the sound-generating component has malfunctioned based on the level change of the feedback signal during the low-level state of the pulse signal, including: The main control module determines whether the sound-generating component has malfunctioned based on the duration of the first level value before the feedback signal changes from the first level value to the second level value during the low-level state of the pulse signal; the first level value is different from the second level value.

23. The method for detecting a sound-generating component according to claim 22, characterized in that, The main control module determines whether the sound-generating component has malfunctioned based on the duration of the first level value before the feedback signal changes from the first level value to the second level value during the low-level state of the pulse signal, including: The main control module compares the duration with the first preset duration and determines whether the sound-generating component has malfunctioned based on the comparison result.

24. The method for detecting a sound-generating component according to claim 23, characterized in that, The sound-generating component detection method further includes: When the duration is not less than a first preset duration, the main control module compares the duration with a second preset duration and determines whether the sound-generating component has experienced a performance failure based on the comparison result; wherein the second preset duration is longer than the first preset duration.

25. The method for detecting a sound-generating component according to claim 20, characterized in that, The main control module determines whether the sound-generating component has malfunctioned based on the level change of the feedback signal during the low-level state of the pulse signal, including: The main control module determines whether the sound-generating component is malfunctioning based on the level value sequence formed by the level values ​​of the feedback signal at multiple detection time points during the low-level state of the pulse signal.

26. The method for detecting a sound-generating component according to claim 25, characterized in that, The main control module determines whether the sound-generating component is malfunctioning based on a sequence of level values ​​formed by multiple detection time points of the feedback signal during the low-level state of the pulse signal, including: The main control module compares the level value sequence with a preset standard sequence and determines whether the sound-generating component has malfunctioned based on the comparison result.

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