High-voltage driving circuit of passive buzzer
By combining the power supply module, voltage control module, drive integration module, signal processing module, and timing control module, the problem of increased circuit complexity in passive buzzers under high voltage was solved, and a compact and high-volume buzzer drive circuit was achieved.
Patent Information
- Application Number
- CN202520033748.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-08
- Publication Date
- 2026-01-27
- Estimated Expiration
- 2035-01-08
AI Technical Summary
When existing passive buzzers are driven at high voltages, the circuit design becomes more complex, resulting in a large size that cannot meet the requirements for miniaturization.
The design employs a combination of a power supply module, a voltage control module, a drive integration module, a signal processing module, and a timing control module. By using PWM signal control and voltage boosting through the voltage control module, the buzzer volume can be output between 140 and 150 decibels.
A compact design of the buzzer driver circuit was achieved, with a volume of 140-150 decibels, simplifying the circuit structure and meeting the demand for high volume.
Smart Images
Figure CN223842618U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of high voltage drive circuit technology, and in particular to a high voltage drive circuit for a passive buzzer. Background Technology
[0002] Buzzers are widely used in most household appliances for audible alerts. Most of these buzzers are active, driven by low voltages of 3.3V-5V, and are small in size but not very loud. However, in situations requiring higher volume, such as air raid warnings and fire alarms, passive buzzers are chosen. These passive buzzers are characterized by increasing volume with voltage, sometimes reaching over 120 decibels. However, due to the limitations of their application environment, buzzers are usually small in size, and high-voltage input involves transformers, solid-state capacitors, and other components. This design generally increases the number of electronic components in the buzzer control circuit, multiplying the complexity of the buzzer drive circuit and ultimately resulting in a large circuit design. Utility Model Content
[0003] This utility model addresses the shortcomings of existing technologies by providing the following technical solution:
[0004] A high-voltage drive circuit for a passive buzzer includes: a power supply module 1, a voltage control module, a drive integration module, a signal processing module, a power supply module 2, and a timing control module;
[0005] Specifically, the first power supply module is electrically connected to the voltage control module, the first power supply module is electrically connected to the drive integration module, the voltage control module is electrically connected to the drive integration module, the drive integration module is electrically connected to the signal processing module, the drive integration module is electrically connected to the second power supply module, the signal processing module is electrically connected to the timing control module, and the second power supply module is electrically connected to the timing control module.
[0006] As an improvement to the above technical solution, the voltage control module includes chip U3, resistors R2, R3, R4, and R5, inductor L1, capacitors C3, C4, C5, C6, and C7, transistor Q3, and diode D2.
[0007] Specifically, the power supply module is electrically connected to one side of the resistor R2 and one side of the inductor L1. The side of the inductor L1 connected to the power supply module is electrically connected to pins 10 and 1 of the chip U3, respectively. One side of the capacitor C3 is connected between the inductor L1 and pin 1 of the chip U3, and the other side of the capacitor C3 is grounded. Pin 2 of the chip U3 is electrically connected to the capacitor C4 and then grounded. Pin 4 of the chip U3 is connected in series with the capacitor C6 and then electrically connected to pin 5 of the chip U3. The capacitor C5 is connected in series with the resistor R6. Capacitor C5 and the other side of resistor R6 are connected in parallel across the two ends of capacitor C6. Pin 6 of chip U3 is grounded. Pin 7 of chip U3 is electrically connected to capacitor C7 and then grounded. Pin 7 of chip U3 is electrically connected to the source (S) of transistor Q3 through resistor R4. Pin 7 of chip U3 is also electrically connected to resistor R5 through resistor R4 and then grounded. Pin 8 of chip U3 is electrically connected to the gate (G) of transistor Q3 through resistor R3. The drain (D) of transistor Q3 is electrically connected to the output terminal of inductor L1 and outputs power through diode D2.
[0008] As an improvement to the above technical solution, the drive integration module includes a buzzer BUZ1, a chip U1, a capacitor C1, a capacitor C2, a diode D1, a transistor Q1, and a transistor Q2.
[0009] Specifically, pin 1 of the buzzer BUZ1 is electrically connected to pin 6 of the chip U1, pin 2 of the buzzer BUZ1 is grounded, one side of capacitor C1 is electrically connected to power supply module one, diode D1, and pin 1 of chip U1 respectively, one side of capacitor C1 is electrically connected to pin 4 of chip U1 and grounded, pin 3 of chip U1 is electrically connected to power supply module two, one side of capacitor C2 is electrically connected to diode D1, one side of capacitor C2 is electrically connected to pin 8 of chip U1, one side of capacitor C2 is electrically connected to pin 6 of chip U1, one side of capacitor C2 is electrically connected to the source (S) of transistor Q1, one side of capacitor C2 is electrically connected to the drain (D) of transistor Q2, pin 7 of chip U1 is electrically connected to the gate (G) of transistor Q1, pin 5 of chip U1 is electrically connected to the gate (G) of transistor Q2, and the source (S) of transistor Q2 is grounded.
[0010] As an improvement to the above technical solution, the signal processing module includes a pulse width modulation signal channel PWM1 and a resistor R1. One side of the pulse width modulation signal channel PWM1 is electrically connected to the resistor R1 and then connected to pin 2 of the chip U1.
[0011] As an improvement to the above technical solution, the timing control module includes a chip U2, pin 9 of the chip U2 is electrically connected to the power supply module, pin 7 of the chip U2 is grounded, and pin 4 of the chip U2 is electrically connected to the pulse width modulation signal channel PWM1.
[0012] The beneficial effects of this utility model are:
[0013] The entire circuit is designed for compactness, employing PWM signal control. A voltage control module amplifies the current output from the power supply module. The signal processing module generates circuits with high-level and low-level operating modes. When the alarm signal is in high-level mode, the buzzer driver circuit is activated; in low-level mode, it is deactivated. The voltage control module regulates the buzzer volume, maintaining it between 140 and 150 decibels. The integrated driver module collects, identifies, and processes signals from each module, issuing timely and accurate commands for optimal instruction delivery. Attached Figure Description
[0014] Figure 1 This is the overall circuit diagram of this utility model;
[0015] Figure 2 This is a circuit diagram of the drive integrated module in this utility model;
[0016] Figure 3 This is a circuit diagram of the timing control module in this utility model;
[0017] Figure 4 This is a circuit diagram of the voltage control module in this utility model.
[0018] Attached reference numerals: 1. Power supply module one; 2. Voltage control module; 3. Drive integration module; 4. Signal processing module; 5. Power supply module two; 6. Timing control module. Detailed Implementation
[0019] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model.
[0020] Most existing buzzers are active buzzers, which can be driven by low voltages of 3.3V-5V. They are small in size but not very loud. However, in situations where a high volume is required, such as air raid warnings and fire alarms, passive buzzers are chosen. These passive buzzers are characterized by increasing volume as the voltage increases, sometimes reaching over 120 decibels. However, due to the limitations of their practical environment, buzzers are usually small in size, and high-voltage inputs involve components such as transformers and solid-state capacitors. This type of design generally increases the number of electronic components in the entire buzzer control circuit, multiplying the complexity of the buzzer driver circuit and ultimately resulting in a large circuit design.
[0021] To resolve this issue, please refer to [link / reference]. Figure 1-4 A high-voltage drive circuit for a passive buzzer includes: a power supply module 1, a voltage control module 2, a drive integration module 3, a signal processing module 4, a second power supply module 5, and a timing control module 6.
[0022] Specifically, the power supply module 1 is electrically connected to the voltage control module 2, the power supply module 1 is electrically connected to the drive integration module 3, the voltage control module 2 is electrically connected to the drive integration module 3, the drive integration module 3 is electrically connected to the signal processing module 4, the drive integration module 3 is electrically connected to the power supply module 5, the signal processing module 4 is electrically connected to the timing control module 6, and the power supply module 5 is electrically connected to the timing control module 6.
[0023] In use, power supply module 1 and power supply module 5 provide power, voltage control module 2 can adjust the current and voltage output by power supply module 1, drive integration module 3 is used to control signal amplification and transmission, signal processing module 4 processes signal input and output, and timing control module 6 is used to control the timing sequence of operations.
[0024] In one embodiment, see Figure 4 The voltage control module 2 includes chip U3, resistors R2, R3, R4, and R5, inductor L1, capacitors C3, C4, C5, C6, and C7, transistor Q3, and diode D2.
[0025] Specifically, the power supply module 1 is electrically connected to one side of the resistor R2 and one side of the inductor L1. The side of the inductor L1 connected to the power supply module 1 is electrically connected to pins 10 and 1 of the chip U3, respectively. One side of the capacitor C3 is connected between the inductor L1 and pin 1 of the chip U3, and the other side of the capacitor C3 is grounded. Pin 2 of the chip U3 is electrically connected to the capacitor C4 and then grounded. Pin 4 of the chip U3 is connected in series with the capacitor C6 and then electrically connected to pin 5 of the chip U3. The capacitor C5 is connected in series with the resistor R6. The capacitor C5 and the other side of the resistor R6 are respectively connected in parallel across the two ends of the capacitor C6. Pin 6 of the chip U3 is grounded. Pin 7 of the chip U3 is electrically connected to the capacitor C7 and then grounded. Pin 7 of the chip U3 is electrically connected to the source (S) of the transistor Q3 through resistor R4. Pin 7 of the chip U3 is electrically connected to the resistor R5 through resistor R4 and then grounded. Pin 8 of the chip U3 is electrically connected to the gate (G) of the transistor Q3 through resistor R3. The drain (D) of the transistor Q3 is electrically connected to the output terminal of the inductor L1 and outputs power through the diode D2.
[0026] In operation, the current starts from the input of power supply module 1, and passes through multiple stages including filtering, step-down conversion, inductor energy storage, capacitor filtering, and feedback control, finally outputting a stable voltage to the load. The current passes through resistor R2 and enters capacitors C3, C4, and C5 for filtering. After filtering, the current enters pin 10 of chip U3. Chip U3 is a step-down DC-DC converter used to convert the input voltage to a lower output voltage. Chip U3 achieves voltage conversion through internal switching circuits and external inductors, capacitors, and other components. The current flows from pin 8 of chip U3 through inductor L1 to diode D2. Inductor L1 stores energy. When the internal switch of chip U3 is turned off, the energy in inductor L1 is released to capacitor C7 and resistor R5. Capacitor C7 is used for filtering to ensure the stability of the output voltage. The voltage divider composed of resistors R3 and R4 is used to feed the output voltage back to pins 6 and 5 of chip U3. This feedback mechanism is used to adjust the internal switching frequency and duty cycle of chip U3 to maintain the stability of the output voltage.
[0027] In one embodiment, see Figure 2 The drive integration module 3 includes a buzzer BUZ1, a chip U1, a capacitor C1, a capacitor C2, a diode D1, a transistor Q1, and a transistor Q2.
[0028] Specifically, pin 1 of the buzzer BUZ1 is electrically connected to pin 6 of the chip U1, pin 2 of the buzzer BUZ1 is grounded, one side of capacitor C1 is electrically connected to power supply module 1, diode D1, and pin 1 of chip U1 respectively, one side of capacitor C1 is electrically connected to pin 4 of chip U1 and grounded, pin 3 of chip U1 is electrically connected to power supply module 2, one side of capacitor C2 is electrically connected to diode D1, one side of capacitor C2 is electrically connected to pin 8 of chip U1, one side of capacitor C2 is electrically connected to pin 6 of chip U1, one side of capacitor C2 is electrically connected to the source (S) of transistor Q1, one side of capacitor C2 is electrically connected to the drain (D) of transistor Q2, pin 7 of chip U1 is electrically connected to the gate (G) of transistor Q1, pin 5 of chip U1 is electrically connected to the gate (G) of transistor Q2, and the source (S) of transistor Q2 is grounded.
[0029] In operation, current flows from power supply module 1, through the control of chip U1, and then through transistors Q1 and Q2 to drive buzzer BUZ1, causing buzzer BUZ1 to sound. The entire circuit controls the working state of buzzer BUZ1 through a PWM signal. When transistor Q1 is turned on, current flows from power supply module 1 through diode D1, pin 7 of chip U1, and the gate and drain of transistor Q1 to one end of buzzer BUZ1. When transistor Q2 is turned on, current flows from the other end of buzzer BUZ1 through the drain and source of transistor Q2 to ground. This alternating conduction method enables buzzer BUZ1 to sound. During operation, capacitors C1 and C2 are used for filtering and stabilizing the power supply voltage, while diode D1 is used to prevent reverse current flow and protect the circuit.
[0030] In one embodiment, see Figure 2-3 The signal processing module 4 includes a pulse width modulation signal channel PWM1 and a resistor R1. One side of the pulse width modulation signal channel PWM1 is electrically connected to the resistor R1 and then connected to pin 2 of the chip U1.
[0031] In use, PWM1 is typically used to receive pulse width modulation, or PWM signal for short. This signal is often used to control the power of electronic devices, such as motor speed control and light brightness adjustment. The signal input to the pulse width modulation signal channel PWM1 will control transistors Q1 and Q2 through chip U1, thereby controlling the buzzer BUZ1 to sound.
[0032] In one embodiment, see Figure 3The timing control module 6 includes a chip U2. Pin 9 of the chip U2 is electrically connected to the power supply module 5, pin 7 of the chip U2 is grounded, and pin 4 of the chip U2 is electrically connected to the pulse width modulation signal channel PWM1.
[0033] During use, pins 9 and 7 of chip U2 are power supply pins. Current enters chip U2 from pin 9 to provide power to the internal circuitry of chip U2, and then flows out from pin 7 to form a loop. Chip U2 is a microcontroller chip with multiple input and output pins, each with different functions, such as PWM output, timer, UART communication, SPI communication, etc. These functions enable it to control various external devices, such as motors, sensors, displays, etc.
[0034] The above embodiments are only used to illustrate the technical solution of this utility model, and are not intended to limit it. Any person skilled in the art can modify or change the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.
Claims
1. A high-voltage drive circuit for a passive buzzer, characterized in that, include: Power supply module 1 (1), voltage control module (2), drive integration module (3), signal processing module (4), power supply module 2 (5), and timing control module (6); Specifically, the power supply module one (1) is electrically connected to the voltage control module (2), the power supply module one (1) is electrically connected to the drive integration module (3), the voltage control module (2) is electrically connected to the drive integration module (3), the drive integration module (3) is electrically connected to the signal processing module (4), the drive integration module (3) is electrically connected to the power supply module two (5), the signal processing module (4) is electrically connected to the timing control module (6), and the power supply module two (5) is electrically connected to the timing control module (6).
2. The high-voltage drive circuit for a passive buzzer according to claim 1, characterized in that: The voltage control module (2) includes chip U3, resistors R2, R3, R4, R5, inductor L1, capacitors C3, C4, C5, C6, C7, transistor Q3, and diode D2. Specifically, the power supply module (1) is electrically connected to one side of the resistor R2 and one side of the inductor L1. The side of the inductor L1 connected to the power supply module (1) is electrically connected to pin 10 and pin 1 of the chip U3, respectively. One side of the capacitor C3 is connected between the inductor L1 and pin 1 of the chip U3. The other side of the capacitor C3 is grounded. Pin 2 of the chip U3 is electrically connected to the capacitor C4 and then grounded. Pin 4 of the chip U3 is connected in series with the capacitor C6 and then electrically connected to pin 5 of the chip U3. The capacitor C5 is connected in series with the resistor R6. The capacitor C5 and the other side of the resistor R6 are respectively connected in parallel across the two ends of the capacitor C6. Pin 6 of the chip U3 is grounded. Pin 7 of the chip U3 is electrically connected to the capacitor C7 and then grounded. Pin 7 of the chip U3 is electrically connected to the source (S) of the transistor Q3 through resistor R4. Pin 7 of the chip U3 is electrically connected to the resistor R5 through resistor R4 and then grounded. Pin 8 of the chip U3 is electrically connected to the gate (G) of the transistor Q3 through resistor R3. The drain (D) of the transistor Q3 is electrically connected to the output terminal of the inductor L1 and outputs power through the diode D2.
3. The high-voltage drive circuit for a passive buzzer according to claim 2, characterized in that: The drive integration module (3) includes a buzzer BUZ1, a chip U1, a capacitor C1, a capacitor C2, a diode D1, a transistor Q1, and a transistor Q2; Specifically, pin 1 of the buzzer BUZ1 is electrically connected to pin 6 of the chip U1, pin 2 of the buzzer BUZ1 is grounded, one side of the capacitor C1 is electrically connected to the power supply module one (1), diode D1 and pin 1 of the chip U1 respectively, one side of the capacitor C1 is electrically connected to pin 4 of the chip U1 and grounded, pin 3 of the chip U1 is electrically connected to the power supply module two (5), one side of the capacitor C2 is electrically connected to the diode D1, one side of the capacitor C2 is electrically connected to pin 8 of the chip U1, one side of the capacitor C2 is electrically connected to pin 6 of the chip U1, one side of the capacitor C2 is electrically connected to the source (S) of the transistor Q1, one side of the capacitor C2 is electrically connected to the drain (D) of the transistor Q2, pin 7 of the chip U1 is electrically connected to the gate (G) of the transistor Q1, pin 5 of the chip U1 is electrically connected to the gate (G) of the transistor Q2, and the source (S) of the transistor Q2 is grounded.
4. The high-voltage drive circuit for a passive buzzer according to claim 3, characterized in that: The signal processing module (4) includes a pulse width modulation signal channel PWM1 and a resistor R1. One side of the pulse width modulation signal channel PWM1 is electrically connected to the resistor R1 and then connected to pin 2 of the chip U1.
5. The high-voltage drive circuit for a passive buzzer according to claim 4, characterized in that: The timing control module (6) includes a chip U2. Pin 9 of the chip U2 is electrically connected to the power supply module (5). Pin 7 of the chip U2 is grounded. Pin 4 of the chip U2 is electrically connected to the pulse width modulation signal channel PWM1.