Micro-grid atomizer control circuit with low noise

Abstract

The invention discloses a micro-grid atomizer control circuit with low noise, a first pin of a USB connector in the micro-grid atomizer control circuit is electrically connected with a right side lead end of a three-pin inductor, a left side lead end of the three-pin inductor is electrically connected with a polar plate of a first capacitor, and a shell of the first capacitor is grounded; a grid electrode of the MOS tube is electrically connected with one end of the first resistor and one end of the second resistor, a shell of the second resistor is grounded, and the other end of the first resistor is connected with PWM signals output by a chip machine. A middle lead end of the three-pin inductor and a fourth pin of the USB connector are electrically connected with a drain electrode of the MOS tube, a source electrode of the MOS tube is electrically connected with one end of the third resistor, and a shell of the third resistor is grounded; the noise of the atomizer is smaller than 45 dB, and the atomizer is friendly to users sensitive to sound; the pulse width modulation (PWM) signal adopted by the invention has the advantages of high flexibility, energy conservation, low hardware requirement and easiness in programming and control.

Description

Technical Field

[0001] The invention belongs to the technical field of atomizers, and in particular relates to a microgrid atomizer control circuit with low noise. Background Art

[0002] At present, diseases such as bronchial asthma, respiratory viral infection and pneumonia are at a high incidence, and aerosol inhalation is one of the most effective methods for treating these diseases. Because the drug directly enters the respiratory tract and lungs, the target organs, through inhalation, it is faster and more effective than oral drugs, and its dosage is only one-tenth of other drug administration methods at most, which significantly reduces the side effects of drugs, especially for children. In inhalation therapy, how to transmit the drug to the patient's respiratory tract and lungs, the inhalation device plays a key role.

[0003] Noise refers to the sound produced when the atomizer is working. The level of noise directly affects the user's comfort and experience. The noise generated by the micro-grid atomizer is related to the power. The higher the power, the greater the noise. Proper adjustment of voltage and power can reduce the noise of the atomizer. In actual operation, the purpose of noise reduction can be achieved through an oscillation circuit. The traditional oscillation circuit uses the NE555 typical astable circuit for oscillation. The NE555 oscillation generates a fixed frequency drive signal.

[0004] Disadvantages of the traditional NE555 oscillation circuit of the atomizer: 1. The output current is small, which is not suitable for directly driving high-power loads. It needs to be driven by an output buffer or other driving circuits. In addition, due to the limitations of its working principle, NE555 is not very suitable for high-frequency and high-precision applications. 2. The power consumption is relatively high. The power consumption of NE555 exceeds that of an NMOS chip, which may become a limitation of its application in some occasions with strict power consumption requirements. 3. Sensitive to static electricity. Although NE555 has many advantages, it is sensitive to static electricity. Therefore, special care should be taken during handling and use to avoid damage caused by static electricity. Summary of the invention

[0005] The invention provides a microgrid atomizer control circuit with low noise to solve the existing problems.

[0006] To solve the above problems, the technical solution provided by the present invention is as follows:

[0007] The embodiment of the present invention provides a microgrid atomizer control circuit with low noise, including a power supply, a single-chip microcomputer, a three-pin inductor L1, a first capacitor C1, a MOS tube and a USB connector, a first resistor R1, a second resistor R2 and a third resistor R3; the power supply is electrically connected to the single-chip microcomputer, the first pin 1 of the USB connector is electrically connected to the right lead terminal 3 of the three-pin inductor L1, the left lead terminal 1 of the three-pin inductor L1 is electrically connected to one plate of the first capacitor C1, and the shell of the first capacitor C1 is grounded; the gate of the MOS tube is electrically connected to one end of the first resistor R1 and the second resistor R2 respectively, the shell of the second resistor R2 is grounded, and the other end of the first resistor R1 is connected to the PWM signal output by the microcontroller; the middle lead terminal 2 of the three-pin inductor L1 and the fourth pin 4 of the USB connector are both electrically connected to the drain of the MOS tube, the source of the MOS tube is electrically connected to one end of the third resistor R3, and the shell of the third resistor R3 is grounded.

[0008] In an optional embodiment of the present invention, when the amplitude of the PWM signal wave is 5V, the MOS tube is turned on, current flows through the three-pin inductor L1, the third resistor R3 and the MOS tube, and the three-pin inductor L1 stores energy.

[0009] In an optional embodiment of the present invention, when the amplitude of the PWM signal wave is 0V, the MOS tube is turned off, and the energy stored in the three-legged inductor L1 is released.

[0010] In an optional embodiment of the present invention, the single chip microcomputer outputs a PWM signal wave through its P0.6 pin.

[0011] In an optional embodiment of the present invention, the power supply is directly provided by a power adapter with a power supply of 5V / 1A.

[0012] Compared with the prior art, the embodiment of the present invention provides a microgrid atomizer control circuit with low noise, which has the following beneficial effects: (1) The level of noise directly affects the user's comfort and use experience. The noise of a better atomizer should be ≤65dB, and the lower the noise, the better. The noise of the atomizer of the present invention is ≤45dB, which is more friendly to sound-sensitive users. (2) The advantages of the pulse width modulation PWM signal of the present invention are: High flexibility: PWM technology allows the microcontroller to generate analog signals in a digital way, thereby realizing precise control of various devices. By adjusting the pulse width, the output voltage or current can be flexibly controlled. Energy saving: PWM controls the output power by adjusting the duty cycle of the signal, thereby achieving the purpose of reducing the power of the device. Low hardware requirements: Compared with using a dedicated analog circuit, the microcontroller system using PWM technology has lower hardware requirements and reduces system costs. Easy to program and control: The generation and control of PWM signals are relatively simple, and most microcontroller programming languages ​​provide direct support for PWM functions. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions in the embodiments or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0014] Figure 1 A schematic diagram of a microgrid atomizer control circuit with low noise provided in an embodiment of the present application.

[0015] Figure 2 A schematic diagram of a boost circuit of a microgrid atomizer control circuit with low noise provided in an embodiment of the present application.

[0016] Figure 3 A schematic diagram of a single chip microcomputer in a microgrid atomizer control circuit with low noise provided in an embodiment of the present application.

[0017] Figure 4 A schematic diagram of a power supply in a microgrid atomizer control circuit with low noise provided in an embodiment of the present application. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0019] like Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, an embodiment of the present invention provides a microgrid atomizer control circuit with low noise, including a power supply, a single-chip microcomputer, a three-pin inductor L1, a first capacitor C1, a MOS tube and a USB connector, a first resistor R1, a second resistor R2 and a third resistor R3; the power supply is electrically connected to the single-chip microcomputer, the first pin 1 of the USB connector is electrically connected to the right lead terminal 3 of the three-pin inductor L1, the left lead terminal 1 of the three-pin inductor L1 is electrically connected to one plate of the first capacitor C1, and the shell of the first capacitor C1 is grounded; the gate of the MOS tube is electrically connected to one end of the first resistor R1 and the second resistor R2 respectively, the shell of the second resistor R2 is grounded, and the other end of the first resistor R1 is connected to the PWM signal output by the microcontroller; the middle lead terminal 2 of the three-pin inductor L1 and the fourth pin 4 of the USB connector are both electrically connected to the drain of the MOS tube, the source of the MOS tube is electrically connected to one end of the third resistor R3, and the shell of the third resistor R3 is grounded.

[0020] The single-chip microcomputer provides a square wave to control the on and off of the MOS tube in the boost resonant circuit. The square wave frequency provided is the resonant frequency of the boost resonant circuit. The three-pin inductor L1 is self-coupled and boosted, and the atomizer starts to work. This embodiment directly uses the single-chip microcomputer to generate a fixed-frequency PWM wave to supply the MOS tube, which is then boosted by a three-pin inductor. The boosted square wave enters the microgrid atomizer, which can break up the water droplets and atomize them.

[0021] The noise generated by the micro-grid atomizer of the present invention in the working state is far lower than the noise range that irritates the human ear, providing a comfortable atomization environment for users. The noise in the working state is lower than 45dB, which is far lower than the most comfortable volume range for the human ear (about 88-92dB), thereby protecting the hearing health of children. The PWM signal wave control method can more accurately control the voltage and power to achieve the effect of reducing noise.

[0022] The three-pin inductor works on the principle of electromagnetic induction. When the input voltage is applied to the inductor, the inductor will generate a magnetic field. The magnetic field will then induce an induced current, forming a cycle of charge accumulation and release in the circuit connected to the inductor. This cycle can increase the input voltage to the required working voltage. When the amplitude of the PWM signal wave is 5V, the MOS tube is turned on, and the current flows through the three-pin inductor L1, the third resistor R3, and the MOS tube, and the three-pin inductor L1 stores energy. When the amplitude of the PWM signal wave is 0V, the MOS tube is turned off, and the energy stored in the three-pin inductor L1 is released. The microgrid atomizer control circuit can boost the value of the input voltage to make the atomizer work through the above circuit principle.

[0023] like Figure 3As shown, the microcontroller outputs a PWM signal wave through its P0.6 pin. Since the PWM signal wave task directly determines the resonant frequency of the resonant circuit, and the effective vibration frequency is one of the most important functions of the entire atomization system. Since the resonant frequency of the microgrid atomizer is relatively high, the ordinary PWM of the microcontroller cannot achieve such a high output frequency. Therefore, we use an enhanced 15-bit PWM signal wave.

[0024] Through a large number of tests, it is found that a higher duty cycle will produce stronger atomization intensity, but it will also increase the power consumption of the atomizer and the consumption of atomizing liquid; a lower duty cycle will produce weaker atomization intensity, but can reduce power consumption and atomizing liquid consumption. The duty cycle of the PWM signal wave is more suitable between 30% and 60%.

[0025] like Figure 4 As shown, the power supply is directly provided by the power adapter with a power supply of 5V / 1A.

[0026] The embodiment of the present invention also provides a microgrid atomizer control method with low noise, comprising the following steps:

[0027] Step 1: The circuit board is electrically connected to the microgrid atomizer, and the power adapter provides power to the circuit board. Step 2: Select a new microgrid atomizer, select the preset gear on the circuit board, and press the start button to start atomization. Step 3: Measure the noise during atomization. Step 4: The test results are shown in Table 1.

[0028] Noise test: Place the noise meter and atomizer on the workbench, adjust the atomization rate to the maximum, and test the noise level at the front, back, left and right of the atomizer at a distance of 1m during normal working hours.

[0029] Table 1

[0030] In summary, although the present invention has been disclosed as above in terms of preferred embodiments, the above preferred embodiments are not intended to limit the present invention. A person skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be based on the scope defined in the claims.

Claims

1. A microgrid atomizer control circuit with low noise, characterized in that: The invention comprises a power supply, a single-chip computer, a three-pin inductor L1, a first capacitor C1, a MOS tube and a USB connector, a first resistor R1, a second resistor R2 and a third resistor R3; the power supply is electrically connected to the single-chip computer, the first pin 1 of the USB connector is electrically connected to the right lead terminal 3 of the three-pin inductor L1, the left lead terminal 1 of the three-pin inductor L1 is electrically connected to one plate of the first capacitor C1, and the shell of the first capacitor C1 is grounded; the gate of the MOS tube is electrically connected to one end of the first resistor R1 and the second resistor R2 respectively, the shell of the second resistor R2 is grounded, and the other end of the first resistor R1 is connected to the PWM signal output by the microcontroller; the middle lead terminal 2 of the three-pin inductor L1 and the fourth pin 4 of the USB connector are both electrically connected to the drain of the MOS tube, the source of the MOS tube is electrically connected to one end of the third resistor R3, and the shell of the third resistor R3 is grounded.

2. A microgrid atomizer control circuit with low noise according to claim 1, characterized in that: When the amplitude of the PWM signal wave is 5V, the MOS tube is turned on, and current flows through the three-pin inductor L1, the third resistor R3 and the MOS tube, and the three-pin inductor L1 stores energy.

3. A microgrid atomizer control circuit with low noise according to claim 2, characterized in that: When the amplitude of the PWM signal wave is 0V, the MOS tube is turned off, and the energy stored in the three-leg inductor L1 is released.

4. The microgrid atomizer control circuit with low noise according to claim 1, characterized in that: The single chip microcomputer outputs a PWM signal wave through its P0.6 pin.

5. The microgrid atomizer control circuit with low noise according to claim 1, characterized in that: The power supply is directly provided by a power adapter with a power supply of 5V / 1A.

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