CN217471272U - Surface acoustic wave drive control circuit and electron cigarette - Google Patents

Abstract

The utility model discloses a surface acoustic wave drive control circuit, include: the device comprises a direct-current power supply circuit module (1), a microcontroller module (2), a high-frequency pulse generating circuit module (3), a band-pass filter circuit module (4), an adjustable switching power supply circuit module (5), a driving amplifying circuit module (6), a resonance network (7), an impedance matching network (8), a transmission line variable-voltage coupler module (9) and a surface acoustic wave atomization chip (10). The utility model also discloses a contain surface acoustic wave drive control circuit's electron cigarette. The surface acoustic wave drive control circuit of the utility model has high output frequency and power stability; when the electronic cigarette is used for the electronic cigarette, the smoke concentration is high, and the smoke particle size is small.

Description

Surface acoustic wave drive control circuit and electronic cigarette

Technical Field

The utility model relates to an electron cigarette field, concretely relates to surface acoustic wave drive control circuit reaches and contains surface acoustic wave drive control circuit's electron cigarette.

Background

Electronic cigarettes are increasingly popular with consumers as a novel low-harm cigarette substitute. Currently, electronic cigarette atomization technologies are mainly classified into three major categories: the first type is an electrothermal atomization electronic cigarette, which mainly supplies power to a resistance wire formed by winding nickel alloy, stainless steel alloy, titanium alloy and the like through a battery, so that the resistance wire generates heat, and then heats cigarette liquid in a heat conduction mode to form smoke for a user to suck. The mode driving control circuit has high conversion efficiency, but the resistance wire can be continuously heated up to 500-600 ℃, so that the smoke liquid can be cracked at high temperature to release harmful components such as aldehydes and the like, thereby having potential safety and health hazards and influencing the smoking experience of users. The second is ultrasonic atomization electronic cigarette, which converts electric energy into vibration mechanical energy with frequency of kHz-3MHz by an ultrasonic transducer, so that a smoke liquid film on the surface of the transducer generates cavitation to form smoke. In this way, the problems of low atomization efficiency of the smoke liquid and difficulty in thinning the particle size of the smoke exist due to the non-concentration of ultrasonic energy and low vibration frequency. The third is Surface Acoustic Wave (SAW) atomized electronic cigarette, which converts electric energy into high-frequency vibration mechanical energy (the frequency is up to 20MHz and above) transmitted along the Surface of a piezoelectric material, the SAW and the smoke liquid on the Surface of the piezoelectric substrate material generate a strong sound induced microflow effect, Surface capillary waves are further excited on the Surface of the smoke liquid, and the smoke liquid forms smoke under the ultrahigh frequency oscillation action of the Surface capillary waves. The particle size of the smoke generated by the method can reach the nanometer level, the smoke liquid does not directly contact with the interdigital transducer, and the method belongs to a non-contact low-temperature atomization technology and is the electronic smoke atomization technology with the most development potential at present. The applicant designs a surface acoustic wave electronic cigarette system for the first time in 2018, and the surface acoustic wave electronic cigarette system is disclosed in Chinese patent ZL 201810076941.1.

Compared with an electrothermal electronic cigarette and an ultrasonic atomization electronic cigarette, the surface acoustic wave atomization electronic cigarette has obvious advantages, but a key factor for preventing the technology from rapidly realizing industrialization is that the energy conversion efficiency of an ultrahigh frequency drive control circuit is low. Most of power of the prior art is converted into heat energy, so that the temperature of a control circuit is greatly increased, the dissipated power is increased, the burning probability of a power device is increased, the power output to an acoustic surface wave atomization chip is correspondingly reduced, the working state of the atomization chip is gradually deteriorated, the generated smoke concentration is gradually reduced, and the suction experience of a user is directly influenced.

The present invention has been made to solve the above problems.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to ultrahigh frequency surface acoustic wave electron cigarette drive control circuit energy conversion efficiency is low among the prior art, output is little, power and frequency stability are poor and overall size scheduling problem on the large side provides a surface acoustic wave electron cigarette drive control circuit and electron cigarette thereof. The utility model discloses a surface acoustic wave drive control circuit energy conversion efficiency is high, output is big, power and frequency stability are high, noise figure is little, the small in size, with low costs longe-lived, uses its surface acoustic wave electron cigarette consumption panel temperature low, safe and stable reliable, smog concentration is high, the smog particle diameter is little, the suction taste is good, portable compact.

The technical scheme of the utility model as follows:

the utility model discloses a first aspect discloses a surface acoustic wave drive control circuit, a serial communication port, it includes: the system comprises a direct current power supply circuit module 1, a Microcontroller (MCU) module 2, a high-frequency pulse generating circuit module 3, a band-pass filter circuit module 4, an adjustable switching power supply circuit module 5, a driving amplifying circuit module 6, a resonant network 7, an impedance matching network 8, a transmission line transformer coupler module 9 and a surface acoustic wave atomizing chip 10.

Preferably, the output end of the dc power supply circuit module 1 is electrically connected to a microcontroller module 2, the output end of the microcontroller module 2 is electrically connected to the control ends of the high-frequency pulse generation circuit module 3 and the adjustable switching power supply circuit module 5, the output end of the high-frequency pulse generation circuit module 3 is electrically connected to the input end of the band-pass filter circuit module 4, and the output ends of the band-pass filter circuit module 4 and the adjustable switching power supply circuit module 5 are electrically connected to the input end of the driving amplification circuit module 6; the output end of the driving amplification circuit module 6 is electrically connected with the input end of the resonance network 7, the output end of the resonance network 7 is electrically connected with the input end of the impedance matching network 8, the output end of the impedance matching network 8 is electrically connected with the input end of the transmission line voltage transformation coupler module 9, and the feedback end of the transmission line voltage transformation coupler module 9 is electrically connected with the signal acquisition end of the microcontroller module 2; the output end of the transmission line voltage transformation coupler module 9 is electrically connected with the surface acoustic wave atomization chip 10 through a coaxial cable. By the structure, the direct current power supply circuit module 1 provides power supply signals for the microcontroller module 2 and the high-frequency pulse generating circuit module 3, the microcontroller module 2 generates high-frequency pulse signals with the same frequency as the characteristic response frequency of the surface acoustic wave atomization chip 10 by controlling the high-frequency pulse generating circuit module 3, the generated high-frequency pulse signals remove interference signals through the band-pass filter circuit module 4 to obtain pure sine wave signals, the microcontroller module 2 simultaneously controls the adjustable switching power supply circuit module 5 to amplify the sine wave signals input to the driving amplification circuit module 6, the amplified signals are matched with the impedance of a load through the impedance matching network 8, the signals matched with the impedance are synthesized into a complete radio frequency signal through the transmission line transformer coupler module 9, and the radio frequency signal is used for providing high-frequency high-voltage excitation signals for the surface acoustic wave atomization chip 10, the surface acoustic wave atomization chip 10 is used for exciting and generating a surface acoustic wave vibration elastic wave signal which can atomize the smoke liquid to form smoke.

Preferably, the dc power circuit module 1 provides a power signal for other circuit modules after a dc power is stabilized by a capacitor filter and a voltage stabilizer; further, the direct current power supply is preferably a direct current 12V rechargeable battery.

Preferably, the high-frequency pulse generating circuit module 3 generates a radio frequency signal by using a Direct Digital Synthesizer (DDS), and the frequency stability of the radio frequency signal is high, thereby completely meeting the requirements of a power amplifier switch.

Preferably, the band-pass filter circuit module 4 adopts a Multi-way negative Feedback active second-order band-pass filter in the form of Multi-level Feedback (MFB).

Preferably, the driving amplifying circuit module 6 adopts a class D power amplifier, and the class D power amplifier is composed of four Metal-oxide-semiconductor Field-effect transistors (MOSFETs), and two of the MOSFETs are connected in parallel to form a push-pull resonant circuit; the signal processed by the band-pass filter circuit module 4 passes through a high-frequency transformer T1 to make two groups of parallel transistors obtain reverse excitation voltage and alternately conduct.

Preferably, the adjustable switching power supply circuit module 5 sets an adjustable resistor corresponding to each of the four MOSFET transistors in the driving amplification circuit module 6, so as to adjust the bias voltage of each transistor to ensure that the final output of each transistor is the same, and to keep the whole system stable.

Preferably, the drains and the sources of the four MOSFET transistors are respectively connected in parallel with a cement resistor, so that the dissipation power of the transistors can be effectively balanced, when the transistors are burnt out, the corresponding drains and the corresponding gates are switched on, the voltage of the drains is fed back to the gates, and the diodes are switched off in the reverse direction, so that the purpose of protecting the voltage stabilizing circuit is achieved.

Preferably, the output power of the two groups of transistors which are respectively connected in parallel is coupled after being subjected to impedance matching, so that the independence of each transistor is ensured, the output difference caused by the individual difference of the transistors is avoided, the stability of the power supply is improved, and each group of transistors are coupled after outputting standard sine wave signals, so that the power synthesis is easier.

Preferably, the two groups of power amplification signals output by the driving amplification circuit module 6 are coupled into a complete radio frequency signal by adopting a transmission line transformer, and the transmission line transformer coupler module 9 has both the transformation performance and the transmission line characteristic, and has the advantages of wide frequency band, small volume and high isolation.

Preferably, the surface acoustic wave atomizing chip 10 is composed of at least a piezoelectric base material and an interdigital transducer attached to the surface of the piezoelectric base material; the piezoelectric substrate material can be lithium niobate, tantalum acid crystal, quartz and other piezoelectric crystals, or can be aluminum nitride, zinc oxide and other piezoelectric film materials, or piezoelectric ceramic body materials; the interdigital transducer can be an electrode in a finger crossing shape such as a straight shape or an arc shape, and the electrode material can be conductive metal with good conductivity such as gold, silver, aluminum, copper and the like.

Preferably, the output signal of the push-pull resonant circuit passes through the resonant network 7 and the impedance matching network 8, and then flows into the transmission line transformer coupler module 9 to be coupled into a complete radio frequency signal, and the synthesized radio frequency signal is connected with the input end of the surface acoustic wave atomization chip 10.

The utility model discloses the second aspect discloses an electron cigarette contains above-mentioned arbitrary any surface acoustic wave drive control circuit.

The utility model has the advantages that:

1. compared with the prior art, the utility model discloses a surface acoustic wave drive control circuit can not only realize about 30MHz the drive control of hyperfrequency surface acoustic wave electron cigarette, and the whole small in size of circuit moreover, energy conversion efficiency can reach more than 80%, and output can reach 15W, and power and frequency stability are high, and noise figure is little, and is with low costs longe-lived.

2. Utilize the utility model discloses drive control circuit's electron cigarette not only has the advantage of surface acoustic wave non-contact low temperature atomization technique, and the low plate temperature of consumption is low (< 60 ℃), and safe and stable reliable, smog concentration is high, the smog particle diameter is little (about 10nm, is less than the particle diameter of electron cigarette sold in the market at present), the suction taste is good, portable compact moreover.

Drawings

Fig. 1 is a block diagram of the surface acoustic wave driving control circuit of the present invention.

Fig. 2 is a schematic diagram of the bandpass filter circuit of the present invention.

Fig. 3 is a schematic diagram of the driving amplifying circuit, the impedance matching network and the coupling circuit of the present invention.

The reference signs are: 1. the device comprises a direct current power supply circuit module, a microcontroller module, a high-frequency pulse generation circuit module, a band-pass filter circuit module, an adjustable switching power supply circuit module, a driving amplification circuit module, a resonant network, an impedance matching network, a transmission line voltage transformation coupler module, a surface acoustic wave atomization chip, a direct current power supply circuit module 2, a microcontroller module 3, a high-frequency pulse generation circuit module, a band-pass filter circuit module 4, a band-pass filter circuit module 5, an adjustable switching power supply circuit module, a driving amplification circuit module 6, a resonant network 7, an impedance matching network 8, a transmission line voltage transformation coupler module 9, a surface acoustic wave atomization chip 10.

Detailed Description

The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. It is obvious that the described embodiments are only a few examples of the present invention, and not all examples. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without any creative effort belong to the protection scope of the present invention.

As shown in fig. 1, the utility model discloses a high efficiency surface acoustic wave electron cigarette drive control circuit, including direct current power supply circuit module 1, microcontroller module 2, high frequency pulse production circuit module 3, band-pass filter circuit module 4, adjustable switching power supply circuit module 5, drive amplifier circuit module 6, resonant network 7, impedance matching network 8, transmission line variable voltage coupler module 9 and surface acoustic wave atomizing chip 10.

In an optional embodiment, the output end of the dc power circuit module 1 is electrically connected to a microcontroller module 2, the output end of the microcontroller module 2 is electrically connected to the high-frequency pulse generating circuit module 3 and the control end of the adjustable switching power circuit module 5, the output end of the high-frequency pulse generating circuit module 3 is electrically connected to the input end of the band-pass filter circuit module 4, and the output ends of the band-pass filter circuit module 4 and the adjustable switching power circuit module 5 are electrically connected to the input end of the driving amplifying circuit module 6; the output end of the driving amplifying circuit module 6 is electrically connected with the input end of the resonant network 7, the output end of the resonant network 7 is electrically connected with the input end of the impedance matching network 8, the output end of the impedance matching network 8 is electrically connected with the input end of the transmission line variable-voltage coupler module 9, and the feedback end of the transmission line variable-voltage coupler module 9 is electrically connected with the signal acquisition end of the microcontroller module 2; the output end of the transmission line voltage transformation coupler module 9 is electrically connected with the surface acoustic wave atomization chip 10 through a coaxial cable.

In an alternative embodiment, the dc power circuit module 1 provides power signals for the microcontroller module 2 and the high-frequency pulse generating circuit module 3, the microcontroller module 2 controls the high-frequency pulse generating circuit module 3 to generate a high-frequency pulse signal having the same frequency as the characteristic response frequency of the surface acoustic wave atomizing chip 10, the generated high-frequency pulse signal passes through the band-pass filter circuit module 4 to remove interference signals and obtain a pure sine wave signal, the microprocessor module 2 simultaneously controls the adjustable switching power circuit module 5 to amplify the sine wave signal input to the driving amplifying circuit module 6, the amplified signal passes through the impedance matching network 8 to realize impedance matching with a load, the signal realizing impedance matching is synthesized into a complete rf signal by the transmission line transformer coupler module 9, the rf signal is used for providing a high-frequency high-voltage excitation signal for the surface acoustic wave atomizing chip 10, the surface acoustic wave atomization chip 10 is used for exciting and generating a surface acoustic wave vibration elastic wave signal which can enable smoke liquid to form smoke.

In one embodiment, the dc power circuit module 1 provides a power signal for other circuit modules after a dc power is stabilized by a capacitor filter and a voltage stabilizer, the dc power is a dc 12V rechargeable battery, the voltage stabilizer is a 78L05 three-port voltage stabilizer, and can output a stable 5V dc voltage to provide a start power for other power modules.

In an optional embodiment, the microcontroller module 2 selects an STM32F103 microprocessor, and the high-frequency pulse generation circuit module 3 generates a radio-frequency signal by using a direct digital frequency synthesizer DDS chip AD9850, so that the frequency stability is high, and the requirements of a power amplifier switch are completely met.

In an alternative embodiment, the band pass filter circuit module 4 employs a multi-feedback active second-order band pass filter in the form of a multi-stage feedback MFB, and the specific implementation is as shown in fig. 2, the amplifier employs an AD8008 chip, where in order to eliminate the self-excitation effect and operate stably, a high-frequency decoupling capacitor C01 is directly connected across between the power supply terminals VCC and VEE, and another decoupling capacitor C02 is grounded.

As shown in fig. 3, in an alternative embodiment, the driving amplifying circuit module 6 employs a class D power amplifier, and specifically includes four MOSFET transistors (N1, N2, N3, and N4), N1 and N2 are connected in parallel, N3 and N4 are connected in parallel, and two of them are connected in parallel to form a push-pull resonant circuit, and a signal processed by the band-pass filter circuit module 4 passes through a high-frequency transformer T1 to make two groups of parallel transistors obtain reverse excitation voltages to be alternately turned on, that is, when N1 and N2 are turned on, N3 and N4 are turned off, and when N3 and N4 are turned on, N1 and N2 are turned off.

In an alternative embodiment, the signal processed by the high frequency transformer T1 is connected to the gate of a MOSFET transistor in the power amplification circuit, the source of the MOSFET transistor is grounded, and the drain is connected to the impedance matching network 8 and the resonant network 7.

In an alternative embodiment, the resonant network 7 mainly includes an LC filter, the drain of each MOSFET transistor has a group of LC resonant filter circuits, and the resonant filter circuits respectively connected to the MOSFET transistors N1, N2, N3, and N4 are respectively denoted as XZ1, XZ2, XZ3, and XZ4, and can output a standard sine wave signal after being filtered by the resonant network.

In an alternative embodiment, the impedance matching network 8 is composed of an LC circuit, the drain of each MOSFET transistor has a group of impedance matching circuits, the impedance matching networks respectively connected to the MOSFET transistors N1, N2, N3, and N4 are respectively denoted as ZK1, ZK2, ZK3, and ZK4, and all output impedance values of the respective paths are matched to be the characteristic impedance of the output line of 50 Ω.

In an alternative embodiment, the drains and sources of the MOSFET transistor groups (N1N2, N3N4) connected in parallel in pairs in the driving amplification circuit module 6 are respectively connected in parallel with a cement resistor (R12, R34), which can effectively balance the dissipation power of the transistors, when the transistors are burned out, the corresponding drains and gates are turned on, the drain voltage is fed back to the gates, and the diodes are turned off in the reverse direction, thereby achieving the purpose of protecting the voltage stabilizing circuit.

In an alternative embodiment, the adjustable switching power supply circuit module 5 is provided with an adjustable resistor RP1, RP2, RP3 and RP4 corresponding to four MOSFET transistors (N1, N2, N3 and N4) in the driving amplifier circuit module 6, respectively, for adjusting the bias voltage of each transistor to ensure that the final output of each transistor is the same, so as to keep the whole system stable.

In an optional embodiment, the output signal of the impedance matching network 8 is electrically connected to the input end of the transmission line transformer coupler module 9, the transmission line transformer coupler has both transformer performance and transmission line characteristics, and combines two reverse signals into a complete rf signal for driving the surface acoustic wave atomizing chip 10, which has the advantages of wide frequency band, small volume and high isolation.

The utility model discloses a when surface acoustic wave drive control circuit is used for the electron cigarette, can realize the stable sinusoidal signal output under the ultrahigh frequency to drive surface acoustic wave atomizing chip and stabilize the atomized smoke liquid. Tests show that the energy conversion efficiency can reach more than 80% and the output power can reach 15W under the frequency of 30 MHz; the smoke particle size for the electronic cigarette is about 10nm, which is lower than the particle size of the current commercial electronic cigarette. Due to the low-temperature characteristic of tobacco liquid atomization and the small particle size of smoke, the smoking taste experience is better.

The embodiments of the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to the above-mentioned embodiments, which are only illustrative and not restrictive, and those skilled in the art can make many forms without departing from the spirit and scope of the present invention, and these forms are within the scope of the present invention.

Claims (9)

1. A surface acoustic wave drive control circuit, comprising: the device comprises a direct-current power supply circuit module (1), a microcontroller module (2), a high-frequency pulse generating circuit module (3), a band-pass filter circuit module (4), an adjustable switching power supply circuit module (5), a driving amplifying circuit module (6), a resonance network (7), an impedance matching network (8), a transmission line transformer coupler module (9) and a surface acoustic wave atomization chip (10); the output end of the direct current power supply circuit module (1) is electrically connected with a microcontroller module (2), the output end of the microcontroller module (2) is electrically connected with the high-frequency pulse generating circuit module (3) and the control end of the adjustable switching power supply circuit module (5), the output end of the high-frequency pulse generating circuit module (3) is electrically connected with the input end of the band-pass filter circuit module (4), the band-pass filter circuit module (4) is electrically connected with the output end of the adjustable switching power supply circuit module (5) and the input end of the driving amplification circuit module (6), the output end of the driving amplification circuit module (6) is electrically connected with the input end of the resonant network (7), the output end of the resonant network (7) is electrically connected with the input end of the impedance matching network (8), and the output end of the impedance matching network (8) is electrically connected with the input end of the transmission line transformer coupler module (9), the feedback end of the transmission line voltage transformation coupler module (9) is electrically connected with the signal acquisition end of the microcontroller module (2); the output end of the transmission line voltage transformation coupler module (9) is electrically connected with the surface acoustic wave atomization chip (10) through a coaxial cable.

2. A surface acoustic wave drive control circuit according to claim 1, wherein said DC power supply circuit block (1) is stabilized by a DC power supply through a capacitor filter and a regulator to supply power signals to other circuit blocks.

3. A surface acoustic wave drive control circuit according to claim 1, wherein said high-frequency pulse generating circuit block (3) generates a radio frequency signal using a direct digital synthesizer.

4. A surface acoustic wave drive control circuit according to claim 1, characterized in that the band-pass filter circuit module (4) employs a multi-path negative feedback active second-order band-pass filter in the form of multi-stage feedback.

5. A surface acoustic wave drive control circuit according to claim 1, wherein said drive amplifier circuit block (6) employs a class D power amplifier, and said class D power amplifier is composed of four mosfets, and two of them are connected in parallel to form a push-pull resonant circuit.

6. A surface acoustic wave drive control circuit according to claim 5, wherein the adjustable switching power supply circuit module (5) is provided with four adjustable resistors respectively connected to the gates of four MOSFETs in the drive amplifier circuit module (6); the drain and the source of each of the four metal-oxide-semiconductor field effect transistors are connected in parallel with a cement resistor.

7. A surface acoustic wave drive control circuit according to claim 1, wherein said surface acoustic wave atomizer chip (10) comprises a piezoelectric base material, and an interdigital transducer attached to a surface of said piezoelectric base material.

8. A surface acoustic wave drive control circuit according to claim 5, wherein the output signal of the push-pull resonant circuit passes through the resonant network (7) and the impedance matching network (8), and then flows into the transmission line transformer coupler module (9) to be coupled into a complete radio frequency signal, and the synthesized radio frequency signal is connected with the input end of the surface acoustic wave atomization chip (10).

9. An electronic cigarette comprising the surface acoustic wave drive control circuit according to any one of claims 1 to 8.

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