Buzzer device, driving system for a buzzer and method thereof

Abstract

A buzzer driving system is electrically connected to a buzzer. The driving system includes a driving unit and a boost unit. The driving unit receives an analog audio signal and outputs a driving voltage to the buzzer according to the analog audio signal. The boost unit is electrically connected to the driving unit and boosts an input voltage to generate an operating voltage to the driving unit. The driving system generates the driving voltage through an analog signal to improve the output audio quality of the buzzer.

Description

[Technical Field]

[0001] The present invention relates to a driving system and method for driving a buzzer, and more particularly to a driving system and method that can drive a buzzer to operate through analog signals. [Previous Technology]

[0002] Buzzers are widely used as sound-generating devices in products such as alarms, multimedia devices, automotive electronic equipment, toys, etc. They can be mainly divided into piezoelectric and electromagnetic types. When the buzzer is powered on, the internal metal plate vibrates in the resonant cavity and produces a sound.

[0003] Existing buzzers are mainly driven by digital signals, so most buzzers can only emit a single tone, and sound details are easily filtered out by the buzzer, resulting in poor output sound quality, which is difficult to compare with the output sound quality of a speaker. However, compared with a speaker, buzzers still have irreplaceable advantages such as small size, large volume, low cost and not easily damaged. Therefore, how to solve the existing problems of buzzers is one of the important issues that related manufacturers want to solve. [Summary of the Invention]

[0004] In view of the above, the object of the present invention is to provide a driving system and method for a buzzer that can drive the operation of a buzzer through an analog signal, so as to improve the sound quality of the buzzer and enable the buzzer to display the sound details in the audio signal.

[0005] To achieve the aforementioned objective, the buzzer driving system of the present invention is electrically connected to a buzzer. The buzzer driving system includes a driving unit and a boost unit. The driving unit receives an analog audio signal and outputs a driving voltage to the buzzer according to the analog audio signal. The boost unit is electrically connected to the driving unit and boosts an input voltage to generate an operating voltage to the driving unit.

[0006] Based on the purpose of this invention, this invention further provides a method for driving a buzzer, comprising: boosting an input voltage to generate an operating voltage; receiving an analog audio signal; and outputting a driving voltage according to the analog audio signal.

[0007] Compared with conventional technology that drives a buzzer through a pulse width modulation signal, the buzzer driving system and method of the present invention generate the driving voltage required by the buzzer through an analog signal, so that the buzzer is no longer limited to only responding to digital signals to emit a single tone, but can display sound quality and sound details comparable to a general loudspeaker through an analog signal, thus ensuring the sound quality emitted by the buzzer.

Implementation Method

[0009] The main objective of this invention is to provide a driving system and method that can drive a buzzer 2 to operate through analog signals, so that the operation of the buzzer 2 is not limited by analog or digital signals, and can benefit from the characteristics of analog signals, so that the sound emitted by the buzzer 2 is no longer just a single tone, but has more sound details.

[0010] The following describes the possible embodiments of the present invention in detail with reference to the accompanying drawings. However, it should be noted that the following implementation details are not intended to limit the scope of the claims made by the present invention, but are only intended to facilitate understanding by those skilled in the art.

[0011] Please refer to Figure 1. The driving system 1 of the buzzer of the present invention is electrically connected to a buzzer 2 and includes a boost unit 10 and a driving unit 20. The driving system 1 of the buzzer is an independent system of the buzzer 2 and is set separately from the buzzer 2. Therefore, it can be directly used on the existing buzzer 2 without adjusting the architecture of the buzzer 2.

[0012] The boost unit 10 can be electrically connected to an external input power source and receive an input voltage provided by the input power source. The boost unit 10 boosts the input voltage to generate an operating voltage and outputs the operating voltage to the drive unit 20. The voltage value of the operating voltage output by the boost unit 10 can be preset to a certain value according to the operating requirements of the drive unit 20 and the buzzer 2. The voltage value of the input voltage may fluctuate depending on the condition of the input power source.

[0013] For example, the operating voltage can be preset to 18V, and the input voltage can fall within the range of 2V to 5V. Regardless of how the input voltage value fluctuates, the boost unit 10 will boost the input voltage to the preset 18V and output it to the drive unit 20 to ensure the stability of the operation of the drive unit 20 and to prevent it from being affected by changes in the input voltage.

[0014] The drive unit 20 is electrically connected to the boost unit 10 and the buzzer 2. The drive unit 20 receives an analog audio signal corresponding to the buzzer 2 and outputs a drive voltage to the buzzer 2 according to the analog audio signal, so that the buzzer 2 emits a sound according to the drive voltage.

[0015] The drive unit 20 is powered by the working voltage provided by the boost unit 10 to maintain operation, and the boost unit 10 uses the working voltage to raise the voltage level of the output stage of the drive unit 20, thereby increasing the voltage value of the drive voltage generated by the drive unit 20 and correspondingly enhancing the volume emitted by the buzzer 2 when driven by the drive voltage.

[0016] Referring to Figures 2 and 3, the driving unit 20 includes a gain control circuit 21, a first-stage amplifier circuit 22, and a second-stage amplifier circuit 23. The gain control circuit 21 amplifies the analog audio signal according to a certain amplification factor to generate a single-ended signal, and the driving unit 20 outputs the driving voltage to the buzzer 2 according to the single-ended signal. The driving unit 20 can set the amplification factor of the gain control circuit 21 accordingly based on the boost factor of the boost unit 10 to boost the input voltage to one of the boost factors of the operating voltage. In other words, the amplification factor corresponds to the boost factor.

[0017] The first-stage amplifier circuit 22 has a first input terminal, a second input terminal, and an output terminal. The first input terminal of the first-stage amplifier circuit 22 is electrically connected to the gain control circuit 21 to receive the single-ended signal. The second input terminal of the first-stage amplifier circuit 22 is electrically connected to a standard voltage ref (Voltage Reference), and the output terminal of the first-stage amplifier circuit 22 is electrically connected to one of the positive terminals of the buzzer 2. After amplifying the single-ended signal, the first-stage amplifier circuit 22 outputs a first voltage through its output terminal.

[0018] The second-stage amplifier circuit 23 has a first input terminal, a second input terminal, and an output terminal. The first input terminal of the second-stage amplifier circuit 23 is electrically connected to the output terminal of the first-stage amplifier circuit 22 to receive the first voltage. The second input terminal of the second-stage amplifier circuit 23 is electrically connected to the standard voltage ref, and the output terminal of the second-stage amplifier circuit 23 is electrically connected to one of the negative terminals of the buzzer 2. After amplifying the first voltage, the second-stage amplifier circuit 23 outputs a second voltage through its output terminal.

[0019] The driving voltage corresponds to the difference between the first voltage and the second voltage. The driving unit 20 outputs the driving voltage to the buzzer 2 through the first stage amplifier circuit 22 and the second stage amplifier circuit 23 to drive the buzzer 2 to emit a sound effect corresponding to the driving voltage.

[0020] In one embodiment, the analog audio signal may include a human voice audio signal, a speech audio signal, or a music audio signal. In one embodiment, the analog audio signal may include an audio signal generated after performing audio signal processing on a specific frequency band of the human voice audio signal, speech audio signal, or music audio signal, wherein the audio signal processing may include, but is not limited to, attenuating or enhancing the intensity of the audio signal in the specific frequency band. In one embodiment, the analog audio signal may include an audio signal generated after low-pass filtering a digital signal (e.g., a PWM signal).

[0021] In the embodiment of FIG2, the gain control circuit 21 of the driving unit 20 is a differential amplifier 211. The differential amplifier 211 has a pair of differential input terminals and an output terminal. The pair of differential input terminals are used to receive the analog audio signal, and the output terminal of the differential amplifier 211 is electrically connected to the first input terminal of the first stage amplifier circuit 22. The differential amplifier 211 amplifies the analog audio signal according to the amplification factor to generate the single-ended signal, and outputs the single-ended signal to the first input terminal of the first stage amplifier circuit 22 through the output terminal. The analog audio signal can be a differential signal. The differential amplifier 211 receives the positive signal in the analog audio signal through one of the positive input terminals of the pair of differential input terminals and receives the negative signal in the analog audio signal through one of the negative input terminals of the pair of differential input terminals.

[0022] In addition to amplifying the voltage of the analog audio signal through the differential amplifier 211, the present invention can also suppress the common-mode noise of the analog audio signal through the differential amplifier 211, thereby improving the quality of the single-ended signal.

[0023] In the embodiment of FIG. 3, the gain control circuit 21 of the driving unit 20 includes an amplifier 212, an input resistor Rin, and a feedback resistor Rf. A negative input terminal of the amplifier 212 is connected in series with the input resistor Rin, and the feedback resistor Rf is connected in series between the negative input terminal and an output terminal of the amplifier 212. A positive input terminal of the amplifier 212 receives the standard voltage ref, and the output terminal of the amplifier 212 is electrically connected to the first input terminal of the first-stage amplifier circuit 22. The amplification factor of the gain control circuit 21 corresponds to the resistance ratio of the feedback resistor Rf to the input resistor Rin. The driving unit 20 can control the amplification factor by adjusting the resistance values ​​of the feedback resistor Rf and the input resistor Rin, wherein the input resistor Rin and the feedback resistor Rf can be variable resistors.

[0024] The buzzer 2 can be a piezoelectric buzzer 2, the main structure of which includes a piezoelectric element, a metal sheet and a housing. The piezoelectric element can be made of piezoelectric ceramic material. When subjected to voltage, the piezoelectric element deforms due to the piezoelectric effect, which drives the metal sheet to vibrate and produce sound. In addition to covering the piezoelectric element and the metal sheet, the housing also constitutes the resonant cavity of the piezoelectric element and the metal sheet.

[0025] Compared with ordinary speakers, the buzzer 2 has the advantages of low power consumption, loud sound, small size, low cost and not easy to damage. Moreover, the structure and material characteristics of the buzzer 2 make it still highly durable and stable in extreme environments such as high temperature or humidity. Compared with speakers that are easily damaged and have a high unit price, the buzzer 2 has irreplaceable advantages.

[0026] Referring to Figure 4, the buzzer driving method of the present invention is applied to the buzzer 2 and can be executed by the buzzer driving system 1. The buzzer driving method includes the following steps:

[0027] S10: Boost an input voltage to generate an operating voltage. Step S10 can be performed by the boost unit 10, and the input voltage is boosted to the operating voltage at a boost ratio.

[0028] S20: Receive an analog audio signal. Step S20 can be executed by the driving unit 20, and the analog audio signal can be a differential signal.

[0029] S30: Output a drive voltage to the buzzer 2 according to the analog audio signal. Step S30 can be executed by the drive unit 20.

[0030] In a preferred embodiment, step S30 sets an amplification factor according to the boost factor, amplifies the analog audio signal by the amplification factor to generate a single-ended signal, and outputs the drive voltage according to the single-ended signal. The drive voltage corresponds to the difference between a first amplified voltage and a second amplified voltage, the first amplified voltage being generated by signal amplification of the single-ended signal, and the second amplified voltage being generated by signal amplification of the first amplified voltage.

[0031] In summary, the buzzer driving system 1 and method of the present invention can process analog audio signals to generate the driving voltage required by the buzzer 2. Compared with the conventional method of driving the buzzer 2 through pulse width modulation signals, the present invention not only allows the buzzer 2 to no longer be limited to being used under digital signals and only emitting a single tone, but also allows the buzzer 2 to retain the sound details of the original audio through analog signals, so that the buzzer 2 can exhibit sound quality comparable to that of a general loudspeaker, while retaining the advantages of the buzzer 2 such as large volume, low component cost and high durability.

[0032] This invention is disclosed herein only by preferred embodiments. However, it should be understood by anyone skilled in the art that the above embodiments are only for describing the invention and are not intended to limit the scope of the patent rights claimed by the invention. Any changes or substitutions that are equivalent to or equivalent to the above embodiments should be interpreted as being covered within the spirit or scope of the invention. Therefore, the scope of protection of this invention should be based on the claims defined below. [Simplified Explanation of the Diagram]

[0008] Figure 1: A block diagram of an embodiment of the driving system for the buzzer of the present invention. Figure 2: Another block diagram of an embodiment of the driving system for the buzzer of the present invention. Figure 3: Another block diagram of an embodiment of the driving system for the buzzer of the present invention. Figure 4: A flowchart of the driving method for the buzzer of the present invention.

Claims

1. A buzzer driving system electrically connected to a buzzer, comprising: a driving unit for receiving an analog audio signal and outputting a driving voltage to the buzzer according to the analog audio signal; and a boost unit electrically connected to the driving unit for boosting an input voltage to generate an operating voltage to the driving unit.

2. The driving system for the buzzer as described in claim 1, wherein, The driver unit includes a gain control circuit, which amplifies the analog audio signal according to a gain factor to generate a single-ended signal; the driver unit outputs the drive voltage to the buzzer according to the single-ended signal.

3. The buzzer driving system as described in claim 2, wherein, The analog audio signal is a differential signal; the gain control circuit includes a differential amplifier having a pair of differential inputs that receive the analog audio signal and output the single-ended signal from an output.

4. The buzzer driving system as described in claim 2, wherein, The drive unit sets the amplification factor according to a boost factor of the input voltage to the operating voltage.

5. The buzzer driving system as described in claim 4, wherein, The gain control circuit includes an amplifier, an input resistor, and a feedback resistor. One negative input terminal of the amplifier is connected in series with the input resistor, and the feedback resistor is connected in series between the negative input terminal of the amplifier and one output terminal of the amplifier. The drive unit adjusts the resistance ratio of the input resistor and the feedback resistor according to the boost ratio to control the amplification factor.

6. The driving system for the buzzer as described in claim 2, wherein, The driving unit includes: a first-stage amplifier circuit electrically connected to the gain control circuit, which outputs a first amplified voltage at an output terminal based on the single-ended signal received at a negative input terminal and a reference voltage received at a positive input terminal; and a second-stage amplifier circuit electrically connected to the output terminal of the first-stage amplifier circuit, which outputs a second amplified voltage at an output terminal based on the first amplified voltage received at a negative input terminal and the reference voltage received at a positive input terminal; wherein the driving voltage corresponds to the difference between the first amplified voltage and the second amplified voltage.

7. A method for driving a buzzer, comprising: boosting an input voltage to generate an operating voltage; receiving an analog audio signal; and outputting a driving voltage based on the analog audio signal.

8. A method for driving a buzzer as described in claim 7, wherein, An amplification factor is set according to a boost factor that boosts the input voltage to the operating voltage; the analog audio signal is amplified according to the amplification factor to generate a single-ended signal, and the drive voltage is output according to the single-ended signal.

9. A method for driving a buzzer as described in claim 8, wherein, The signal amplifies the single-ended signal to generate a first amplified voltage, and the signal amplifies the first amplified voltage to generate a second amplified voltage, the drive voltage corresponding to the difference between the first amplified voltage and the second amplified voltage.

10. A method for driving a buzzer as described in claim 7, wherein, The analog audio signal is a differential signal.

Images