Buzzer driving circuit, electronic equipment and electrical equipment

Abstract

The utility model discloses a buzzer driving circuit, electronic equipment and electrical equipment, relates to the technical field of power electronics, and realizes adjustability of the volume of a buzzer. The buzzer driving circuit comprises a sound adjusting circuit and a buzzer access port. The buzzer access port is an interface for accessing a buzzer; the sound adjusting circuit and the buzzer access port are connected in series between a power supply and the ground; the sound adjusting circuit is a parallel circuit, the parallel circuit is composed of n branches, n is larger than or equal to 2, a resistance circuit and a controllable switch are connected in series in each branch, and the control end of the controllable switch in each branch is used for being connected with a control unit.

Description

Technical Field

[0001] This application relates to the field of power electronics technology, and particularly to a buzzer driving circuit, an electronic device, and an electrical appliance device. Background Art

[0002] Buzzers are widely used in various electronic devices to give alarms, reminders, or prompts, etc. The volume requirements for buzzers in electronic devices may vary in different scenarios. However, most of the existing buzzers on the market have a fixed and non-adjustable volume, making it difficult to meet diverse usage requirements. Utility Model Content

[0003] In view of the above problems, this application provides a buzzer driving circuit, an electronic device, and an electrical appliance device to achieve the adjustability of the buzzer volume. The specific solutions are as follows:

[0004] In a first aspect of this application, a buzzer driving circuit is provided, including: a sound adjustment circuit and a buzzer access port;

[0005] The buzzer access port is an interface for accessing a buzzer;

[0006] The sound adjustment circuit is connected in series between the power supply and the ground with the buzzer access port;

[0007] The sound adjustment circuit is a parallel circuit, which is composed of n branches, where n≥2. A resistance circuit and a controllable switch are connected in series inside each branch, and the control ends of the controllable switches in each branch are all used to access a control unit.

[0008] In a possible implementation, the controllable switch in each branch includes: a switching tube, a resistance circuit connected between the control electrode of the switching tube and the control end of the controllable switch, and a resistance circuit connected between the output electrode of the switching tube and the control end of the controllable switch;

[0009] The input electrode of the switching tube is connected to the power supply.

[0010] In a possible implementation, the buzzer driving circuit further includes: a resistance circuit connected in parallel with the buzzer access port.

[0011] In a possible implementation, the buzzer driving circuit further includes: an (n + 1)-th controllable switch;

[0012] The (n + 1)-th controllable switch is connected between the buzzer access port and the ground; the control end of the (n + 1)-th controllable switch is used to access the control unit.

[0013] In a possible implementation, the (n + 1)-th controllable switch includes: a switching transistor, a resistor circuit connected between the switching transistor and the control terminal of the (n + 1)-th controllable switch, and a capacitor connected between the control electrode and the output electrode of the switching transistor.

[0014] In a possible implementation, the buzzer driving circuit further includes: a resistor-capacitor series circuit;

[0015] One end of the resistor-capacitor series circuit is connected to the connection point between the sound adjustment circuit and the buzzer access port, and the other end is grounded.

[0016] A second aspect of the present application provides an electronic device, including: the buzzer driving circuit according to the first aspect or any implementation manner of the first aspect, and a buzzer connected to the buzzer driving circuit.

[0017] In a possible implementation, the electronic device is an air conditioner remote controller.

[0018] A third aspect of the present application provides an electrical appliance device, including: the electronic device according to the second aspect or any implementation manner of the second aspect.

[0019] In a possible implementation, the electrical appliance device is an air conditioner.

[0020] With the above technical solution, the buzzer driving circuit provided by the present application connects multiple resistor circuits in parallel and then connects them in series with the same buzzer. By changing the combination of the on-off states of these resistor circuits (that is, changing the combination mode of the closing and opening states of the n controllable switches in the sound adjustment circuit), the magnitude of the current flowing through the buzzer can be changed, thereby realizing the adjustment of the buzzer volume. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In combination with the accompanying drawings and with reference to the following specific implementation manners, the above and other features, advantages, and aspects of the various embodiments of the present disclosure will become more obvious. Throughout the drawings, the same or similar reference numerals represent the same or similar elements. It should be understood that the drawings are schematic, and the original elements and elements are not necessarily drawn to scale.

[0022] Figure 1 is a schematic diagram of a buzzer driving circuit provided by the present application;

[0023] Figure 2 is a schematic diagram of another buzzer driving circuit provided by the present application;

[0024] Figure 3 is a schematic diagram of another buzzer driving circuit provided by the present application;

[0025] Figure 4 is a schematic diagram of another buzzer driving circuit provided by the present application;

[0026] Figure 5 This is the schematic diagram of another buzzer driving circuit provided for this application;

[0027] Figure 6 This is the schematic diagram of another buzzer driving circuit provided for this application. Detailed implementation manners

[0028] A buzzer is an electronic device that can emit a buzzing sound. It generates vibrations through a piezoelectric sheet or electromagnetic coil inside, and then drives the air to vibrate to produce sound. Buzzers are widely used in various electronic devices to issue alarms, reminders, or notifications, etc.

[0029] The volume requirements for the buzzer to sound in different scenarios of electronic devices may vary. Taking the application of the buzzer in an air conditioner remote controller, an electronic device, as an example:

[0030] An air conditioner remote controller is a device that connects the indoor unit and the outdoor unit of an air conditioner. Its main function is to control and adjust the operating state and functions of the air conditioner by wired means under the operation of the user, controlling the electronic control board built into the indoor unit. Common functions of the air conditioner remote controller include temperature adjustment, wind speed control, mode selection (such as cooling, heating, air supply, dehumidification, etc.), timing function, etc., as well as other possible functions such as sleep mode, ventilation, negative ions, etc. When the user normally presses the buttons on the air conditioner remote controller, the buzzer inside the air conditioner remote controller should emit a small-volume sound as the button press sound to avoid discomfort caused by too loud button press sound.

[0031] In addition, refrigerants are needed in the refrigeration process of an air conditioner. The leakage of refrigerants will not only cause environmental pollution but also may cause great harm to human health. Therefore, modern air conditioner designs usually require a refrigerant leakage alarm function to detect refrigerant leakage in time, repair it in time, and reduce potential risks. As the main interaction device between the user and the air conditioner system, the air conditioner remote controller plays an important role in the refrigerant leakage alarm system. When refrigerant leakage is detected, the buzzer inside the air conditioner remote controller should emit a large-volume sound as the alarm sound to alert the user.

[0032] It can be seen that the air conditioner remote controller requires the internal buzzer to be able to emit a small-volume button press sound during normal button use, and the internal buzzer to be able to emit a large-volume alarm sound in case of an emergency. However, most of the existing buzzers on the market have a fixed and non-adjustable volume, making it difficult to meet diverse usage requirements.

[0033] To meet the different requirements for the buzzer volume of electronic devices in different scenarios, a feasible solution is to expand the number of buzzers used in the electronic device from one to multiple, and connect different resistors in series to different buzzers so that the current intensity (i.e., the magnitude of the current) flowing through different buzzers is unequal. The buzzer will emit sounds of different volumes when driven by different current intensities. The greater the current intensity, the louder the sound emitted by the buzzer. Then, according to the volume requirements of different scenarios, selectively turn on the corresponding buzzer to achieve the volume effect matching the current scenario. Still taking the buzzer applied in the air conditioner remote control as an example, the air conditioner remote control needs to use two buzzers. One buzzer is connected in series with a large resistor in the circuit to reduce the current flowing through the buzzer and emit a low-volume key sound, and the other buzzer is connected in series with a small resistor in the circuit to increase the current flowing through the buzzer and emit a high-volume alarm sound.

[0034] However, although the above solution realizes the adjustability of the buzzer volume, since multiple buzzers need to be used, the cost is relatively high.

[0035] To meet the different requirements for the buzzer volume of electronic devices in different scenarios in a low-cost manner, the embodiment of the present application discloses a buzzer driving circuit. The buzzer driving circuit connects multiple resistor circuits in parallel and then connects them in series with the same buzzer. By changing the on-off state combination of these resistor circuits, the magnitude of the current flowing through the buzzer can be changed, thereby realizing the adjustment of the buzzer volume. That is, according to the volume requirements of different scenarios, selectively turn on the corresponding resistor circuit to achieve the volume effect matching the current scenario. The embodiment of the present application only uses one buzzer to emit sounds of different volumes, and the circuit cost is low.

[0036] Next, in conjunction with the accompanying drawings, the technical solution of the buzzer driving circuit disclosed in the embodiment of the present application will be described in detail. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention. As those of ordinary skill in the art know, with the development of technology and the emergence of new scenarios, the technical solution provided by the embodiment of the present application is also applicable to similar technical problems.

[0037] In the description, claims and the above-mentioned drawings of this application, terms such as "first" and "second" are used to distinguish similar objects, and do not necessarily describe a specific order or sequence. It should be understood that such terms can be interchanged under appropriate circumstances, which is only a way of distinguishing objects with the same attributes when describing embodiments of this application. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, so that a process, method, system, product or device including a series of units does not have to be limited to those units, but may include other units not clearly listed or inherent to these processes, methods, products or devices.

[0038] See Figure 1 , a buzzer driving circuit provided by an embodiment of this application includes: a sound adjustment circuit and a buzzer access port;

[0039] The buzzer access port is an interface for accessing buzzer B1;

[0040] The sound adjustment circuit is connected in series with the buzzer access port between power supply VCC and ground;

[0041] The sound adjustment circuit is a parallel circuit, and the parallel circuit is composed of n branches, n≥2. A resistance circuit and a controllable switch are connected in series inside each branch, and the control end of the controllable switch in each branch is used to access a control unit ( Figure 1 not shown in the figure).

[0042] For ease of description, these n branches are respectively named branch Z1, branch Z2, branch Z3,..., branch Zn, the resistance circuit in branch Zi is named resistance circuit i; the controllable switch in branch Zi is named controllable switch Ki; i = 1, 2, 3,..., n.

[0043] Next, in conjunction with Figure 1 , the working principle of the embodiment of this application will be described in detail:

[0044] After correctly inserting or soldering the two pins of buzzer B1 to the buzzer access port and connecting the control ends of controllable switches K1 to controllable switches Kn to the control unit, the control unit can control the closing and opening of controllable switches K1 to controllable switches Kn. When at least one of the controllable switches K1 to controllable switches Kn is closed, both ends of the sound adjustment circuit are connected; when the at least one controllable switch is opened, both ends of the sound adjustment circuit are disconnected.

[0045] The sound adjustment circuit has two states: connected at both ends and disconnected at both ends. When the two ends of the sound adjustment circuit are connected, current will flow through the buzzer B1, causing the buzzer B1 to emit sound; when the two ends of the sound adjustment circuit are disconnected, no current will flow through the buzzer B1, and the buzzer B1 stops emitting sound. The state switching frequency of the sound adjustment circuit determines the sounding frequency of the buzzer B1. And the sounding frequency of the buzzer B1 affects the pitch of the buzzer B1. The higher the sounding frequency of the buzzer B1, the higher the pitch of the buzzer B1. Therefore, by adjusting the state switching frequency of the sound adjustment circuit, the pitch of the buzzer B1 can be adjusted.

[0046] The volume of the sound emitted by the buzzer B1 depends on the current intensity flowing through the buzzer B1. The greater the current intensity, the greater the volume of the sound emitted by the buzzer B1. Then, according to the volume requirements in different scenarios, the control unit selectively closes the corresponding controllable switches, which can change the total resistance value of the sound adjustment circuit, and further change the current intensity flowing through the buzzer B1 after the two ends of the sound adjustment circuit are connected, so that the volume of the sound emitted by the buzzer B1 meets the requirements of the scenario. Among them, selectively closing the corresponding controllable switches means selectively changing the on-off state combination of n resistor circuits in the sound adjustment circuit, that is, selectively changing the combination method of the on and off states of n controllable switches in the sound adjustment circuit.

[0047] Still taking the buzzer applied to the air conditioner wire controller as an example, assuming n = 3, for the following scenarios 1 to 3, there are:

[0048] Scenario 1. The scenario where the user normally presses the buttons on the air conditioner wire controller:

[0049] When the user normally presses the buttons on the air conditioner wire controller, the control unit can control the controllable switch K1 to open and close at a relatively low frequency, and the controllable switches K2 and K3 remain off. At this time, the current flowing through the buzzer B1 is small and the sounding frequency of the buzzer B1 is low, so that the buzzer B1 can emit a soft sound with a small volume as the button press sound.

[0050] Scenario 2. The scenario where the refrigerant leakage concentration is relatively low:

[0051] When the refrigerant leakage is detected but the refrigerant leakage concentration is low (taking Freon as an example of the refrigerant, it is generally stipulated internationally that the concentration of Freon in the air below 0.1 ppm is safe. When the concentration of Freon in the air is detected to exceed 0.1 ppm but be lower than 0.2 ppm, it is considered that the refrigerant leakage concentration is low; when the concentration of Freon in the air is detected to exceed 0.2 ppm, it is considered that the refrigerant leakage concentration is high), the control unit can control the controllable switches K1~K2 to open and close synchronously at a relatively high frequency (opening and closing synchronously means opening and closing at the same time), and the controllable switch K3 remains open. At this time, the current flowing through the buzzer B1 is large and the sounding frequency of the buzzer B1 is high, so that the buzzer B1 can emit a louder and sharper sound as an alarm sound.

[0052] Scenario 3. Scenario with a high refrigerant leakage concentration:

[0053] When the refrigerant leakage concentration is high, the control unit can control the controllable switches K1~K3 to open and close synchronously at an even higher frequency. At this time, compared with Scenario 2, the current flowing through the buzzer B1 is even larger and the sounding frequency of the buzzer B1 is even higher, so that the buzzer B1 can emit a louder and sharper sound as an alarm sound.

[0054] Of course, for some electronic devices, the buzzer B1 can also maintain a fixed tone. At this time, keep the state switching frequency of the sound adjustment circuit as a fixed value, and only change the combination mode of the closing and opening states of n controllable switches according to the scenario change.

[0055] The embodiment of the present application can meet the different requirements of the electronic device for the buzzer volume in different scenarios only by using one buzzer. Moreover, the cost of the controllable switches introduced in the embodiment of the present application is much lower than that of the buzzer, so the overall cost is low.

[0056] In a possible implementation, the controllable switch in each branch includes: a switching tube, a resistor circuit connected between the control electrode of the switching tube and the control end of the controllable switch, and a resistor circuit connected between the output electrode of the switching tube and the control end of the controllable switch; the input electrode of the switching tube is connected to the power supply VCC. In addition, the resistor circuit mentioned in the embodiment of the present application can be a single resistor or a series-parallel combination of multiple resistors.

[0057] Taking n = 3 as an example, see Figure 2, the switching transistor in the controllable switch K1 is the switching transistor Q1, the resistor circuit connected between the control electrode of the switching transistor Q1 and the control terminal of the controllable switch K1 is the resistor R1, and the resistor circuit connected between the output electrode of the switching transistor Q1 and the control terminal of the controllable switch K1 is the resistor R2; the switching transistor in the controllable switch K2 is the switching transistor Q2, the resistor circuit connected between the control electrode of the switching transistor Q2 and the control terminal of the controllable switch K2 is the resistor R4, and the resistor circuit connected between the output electrode of the switching transistor Q2 and the control terminal of the controllable switch K2 is the resistor R5; the switching transistor in the controllable switch K3 is the switching transistor Q3, the resistor circuit connected between the control electrode of the switching transistor Q3 and the control terminal of the controllable switch K3 is the resistor R7, and the resistor circuit connected between the output electrode of the switching transistor Q3 and the control terminal of the controllable switch K3 is the resistor R8; the resistor circuit 1 is the resistor R3, the resistor circuit 2 is the resistor R6, and the resistor circuit 3 is the resistor R9.

[0058] Still referring to Figure 2 , in the controllable switch K1, the level of the control electrode of the switching transistor Q1 determines whether the switching transistor Q1 is in the on or off state; the resistor R1 mainly functions as a current limiter; the resistor R2 is a bias resistor, which can ensure that the switching transistor Q1 operates under appropriate working conditions and provides stable and reliable circuit performance. Taking the above scenario 1 as an example, the control unit can control the switching frequency of the controllable switch K1 by outputting a PWM (Pulse Width Modulation) signal to the control terminal of the controllable switch K1, and then control the state switching frequency of the sound adjustment circuit to obtain a soft key tone. The structures of the controllable switches K2 to Kn are the same as that of the controllable switch K1 and will not be elaborated here.

[0059] The switching transistor mentioned in the embodiments of the present application can be a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor), an IGBT (Insulated Gate Bipolar Transistor), or a triode. When the switching transistor is a MOSFET, the input electrode of the switching transistor is the drain of the MOSFET, the output electrode of the switching transistor is the source of the MOSFET, and the control electrode of the switching transistor is the gate of the MOSFET. When the switching transistor is an IGBT, the input electrode of the switching transistor is the collector of the IGBT, the output electrode of the switching transistor is the emitter of the IGBT, and the control electrode of the switching transistor is the gate of the IGBT. When the switching transistor is a triode, the input electrode of the switching transistor is the collector of the triode, the output electrode of the switching transistor is the emitter of the triode, and the control electrode of the switching transistor is the base of the triode.

[0060] In a possible implementation, referring to Figure 3, any of the buzzer driving circuits disclosed above further includes: a resistor circuit connected in parallel with the buzzer access port ( Figure 3 taking only this resistor circuit as resistor R11 as an example in

[0061] ). Specifically, since the impedance of buzzer B1 itself is very small, it is very easy to be affected by external interference and have problems. To solve this problem, a resistor can be connected in parallel across buzzer B1 to play the roles of current limiting, voltage limiting and amplitude stabilization, making the sound quality of buzzer B1 better and more stable.

[0062] In a possible implementation, referring to Figure 4 , any of the buzzer driving circuits disclosed above further includes: a controllable switch S1 connected between the buzzer access port and the ground, and the control end of the controllable switch S1 is used to access the control unit.

[0063] The controllable switch S1 can be used to turn off the sound of buzzer B1 with one key and be used as a switch to adjust the sounding frequency of buzzer B1. At this time, controllable switches K1~controllable switches Kn are only used as switches to adjust the sounding volume of buzzer B1, thus avoiding the need for synchronous control of multiple switches (there is a difficulty in synchronous control when controlling multiple controllable switches among controllable switches K1~controllable switches Kn to turn on and off simultaneously).

[0064] In a possible implementation, still referring to Figure 5 , the controllable switch S1 includes: a switching transistor Q4, a resistor circuit connected between the switching transistor Q4 and the control end of the controllable switch S1 ( Figure 5 taking only this resistor circuit as resistor R12 as an example in

[0065] ), and a capacitor C1 connected between the control electrode and the output electrode of the switching transistor Q4. Resistor R12 mainly plays a role in current limiting, and capacitor C1 mainly plays roles such as suppressing self-excited oscillation and filtering, which are used to ensure the stability and performance of the switching transistor Q4 in the circuit. The switching transistor Q4 can be a MOSFET, an IGBT, or a triode. Figure 6 , any of the buzzer driving circuits disclosed above further includes: a resistor-capacitor series circuit, one end of the resistor-capacitor series circuit is connected to the connection point between the sound adjustment circuit and the buzzer access port, and the other end is grounded;

[0066] The resistor-capacitor series circuit includes: a capacitor E1, and a resistor circuit connected in series with the capacitor E1 ( Figure 6 taking only this resistor circuit as resistor R10 as an example in

[0067] Specifically, when the buzzer B1 is powered off, the charge stored in the capacitor E1 gradually decreases. As the charge on the capacitor E1 gradually decreases, the buzzer B1 emits a lingering sound, and the volume of this lingering sound gradually becomes smaller until it disappears, which is very beautiful. The resistor R10 is mainly used to reduce the charging and discharging current of the capacitor E1 and lower the charging and discharging speed of the capacitor E1.

[0068] In any of the above-disclosed embodiments, the sounding frequency of the buzzer B1 can be set according to actual needs. In some electronic devices, by adjusting the sounding frequency of the buzzer B1, it is even possible to produce the effects of do, re, mi, fa, sol, la, si, and precisely control the playing of songs.

[0069] The embodiment of the present application also discloses an electronic device, which includes: any of the buzzer driving circuits disclosed above, and a buzzer connected to the buzzer driving circuit.

[0070] In a possible implementation, the electronic device is, for example, an air conditioner wired controller.

[0071] The embodiment of the present application also discloses an electrical appliance device, which includes: any of the electronic devices disclosed above.

[0072] In a possible implementation, the electrical appliance device is, for example, an air conditioner. An air conditioner itself is a complex system, which mainly consists of several parts such as a refrigeration / heating cycle system, an air circulation and ventilation system, an electrical control system, and a cabinet (including a bottom plate, etc.). An air conditioner wired controller is a control component in the air conditioner's electrical control system, which is responsible for receiving user operation instructions and controlling the operating state of the air conditioner indoor unit in a wired manner.

[0073] In this specification, the various embodiments are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts among the various embodiments can be referred to each other. For the electronic devices and electrical appliance devices disclosed in the embodiments, since they include all the features of the buzzer driving circuit disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the relevant descriptions of the buzzer driving circuit part.

[0074] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the embodiments of the present invention. Therefore, the embodiments of the present invention will not be limited to these embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A buzzer driving circuit, characterized in that: include: Sound adjustment circuit and buzzer access port; The buzzer access port is an interface for accessing a buzzer; The sound adjustment circuit and the buzzer access port are connected in series between the power supply and the ground; The sound adjustment circuit is a parallel circuit, which consists of n branches, n≥2, each branch has a resistance circuit and a controllable switch connected in series, and the control end of the controllable switch in each branch is used to access the control unit.

2. The buzzer driving circuit according to claim 1, characterized in that: The controllable switch in each branch includes: a switch tube, a resistance circuit connected between a control electrode of the switch tube and a control end of the controllable switch, and a resistance circuit connected between an output electrode of the switch tube and the control end of the controllable switch; The input pole of the switch tube is connected to the power supply.

3. The buzzer driving circuit according to claim 1, characterized in that: The buzzer driving circuit further includes: a resistance circuit connected in parallel with the buzzer access port.

4. The buzzer driving circuit according to claim 1, characterized in that: The buzzer driving circuit further includes: an n+1th controllable switch; The n+1th controllable switch is connected between the buzzer access port and the ground; and the control end of the n+1th controllable switch is used to access the control unit.

5. The buzzer driving circuit according to claim 4, characterized in that: The n+1th controllable switch includes: a switch tube, a resistance circuit connected between the switch tube and the control end of the n+1th controllable switch, and a capacitor connected between the control electrode and the output electrode of the switch tube.

6. The buzzer driving circuit according to any one of claims 1 to 5, characterized in that: The buzzer driving circuit further includes: a resistor-capacitor series circuit; One end of the resistor-capacitor series circuit is connected to the connection point between the sound adjustment circuit and the buzzer access port, and the other end is grounded.

7. An electronic device, characterized in that: include: A buzzer driving circuit as claimed in any one of claims 1 to 6, and a buzzer connected to the buzzer driving circuit.

8. The electronic device according to claim 7, characterized in that: The electronic device is an air conditioner wire controller.

9. An electrical device, characterized in that: include: The electronic device as claimed in claim 7 or 8.

10. The electrical equipment according to claim 9, characterized in that: The electrical equipment is an air conditioner.

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