Radio frequency heating assembly and aerosol generating device

Abstract

The utility model discloses a radio frequency heating assembly and an aerosol generating device, and relates to the technical field of microwave heating, the radio frequency heating assembly comprises a microwave signal source, a push amplifier, a final amplifier and a heating structure, a microwave signal generated by the microwave signal source is amplified by the push amplifier and the final amplifier in sequence and is transmitted to the heating structure, and the heating structure is used for heating an object to be heated through microwaves; the microwave signal is amplified to a first preset power through the push amplifier and is amplified to a second preset power through the final amplifier, and the push amplifier and the final amplifier are discrete chips. According to the embodiment of the utility model, the heat output stability of the radio frequency heating assembly can be improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to microwave heating technical field especially relates to a radio frequency heating assembly and aerosol generating device. BACKGROUND

[0002] The principle of microwave heating is that the spin vibration friction of polar molecular material generates heat in the high-frequency electric field environment, and the heated medium receives microwave energy to increase the temperature. This technology is widely used in many fields. In the field of electronic atomization technology, the microwave / radio frequency heating type aerosol generating device can quickly heat and generate aerosol without long preheating time.

[0003] The radio frequency heating assembly and aerosol generating device use a microwave radio frequency generator (microwave source) as an energy source. The following problems exist: multi-stage power amplification modules are arranged on the same substrate to form an integrated chip, and the efficiency of each stage of amplifier is between 30% and 70%. During operation, a large amount of heat is generated, especially in the last stage of amplifier, which generates a large amount of heat consumption because of the maximum output power. The heat consumption generated in the last stage is quickly conducted to the front small signal amplifier, and the gain is sensitive to heat. This leads to rapid changes in overall gain during operation, thereby affecting the unstable heat output of the radio frequency heating assembly. SUMMARY

[0004] Therefore, the radio frequency heating assembly and aerosol generating device can improve the heat output stability of the radio frequency heating assembly.

[0005] In one aspect, the utility model provides a radio frequency heating assembly, including microwave signal source, push amplifier, last stage amplifier and heating structure, wherein: microwave signal generated by the microwave signal source is amplified and transmitted to the heating structure through the push amplifier and the last stage amplifier in turn, the heating structure is used for heating the article to be heated by microwave, the microwave signal is amplified to the first preset power through the push amplifier and is amplified to the second preset power through the last stage amplifier, and the push amplifier and the last stage amplifier are discrete chips.

[0006] Optionally, the last stage amplifier includes a third generation semiconductor GaN power amplifier.

[0007] Optionally, the range of the first preset power includes 0.4W-1W.

[0008] Optionally, the range of the second preset power includes 10W-30W.

[0009] Optionally, the push amplifier comprises a first chip, a plurality of filter circuits and a first matching network, the first chip comprises a plurality of stages of amplification circuits, the power supply of each stage of the amplification circuits is connected to the first chip through the filter circuits, and the output of the first chip is connected to the output port of the push amplifier through the first matching network.

[0010] Optionally, the push amplifier comprises a first filter circuit, a second filter circuit and a third filter circuit, the first chip comprises a first stage of amplification circuits, a second stage of amplification circuits and a third stage of amplification circuits, the input microwave signal is connected to the input port of the first chip through a direct current blocking capacitor, a first power supply is connected to the power input port of the first stage of amplification circuits through the first filter circuit, a second power supply is connected to the power input port of the second stage of amplification circuits through the second filter circuit, the first matching network is connected to the output port of the first chip and the output port of the push amplifier, and a third power supply is connected to the first matching network through the third filter circuit.

[0011] Optionally, the first filter circuit comprises a first resistor, a third capacitor and a sixth capacitor, the second filter circuit comprises a first capacitor and a fourth capacitor, and the third filter circuit comprises a second capacitor, a fifth capacitor and a first inductor; one end of the first resistor is connected to the first power supply, the other end of the first resistor is connected to the power input port of the first stage of amplification circuits, two ends of the third capacitor are respectively connected to one end of the first resistor and a ground terminal, and two ends of the sixth capacitor are respectively connected to the other end of the first resistor and the ground terminal; two ends of the first capacitor and the fourth capacitor are respectively connected to the second power supply and the ground terminal; one end of the first inductor is connected to the third power supply, the other end of the first inductor is connected to the first matching network, and two ends of the second capacitor and the fifth capacitor are respectively connected to the third power supply and the ground terminal.

[0012] Optionally, the final stage of amplification circuits comprises a second matching network, a GaN power amplifier, a third matching network, a fourth filter circuit and a fifth filter circuit, the input microwave signal is connected to the gate port of the GaN power amplifier through the second matching network, a gate power supply is connected to the second matching network through the fourth filter circuit, the drain port of the GaN power amplifier is connected to the output port of the final stage of amplification circuits through the third matching network, and a drain power supply is connected to the third matching network through the fifth filter circuit.

[0013] Optionally, the fourth filter circuit includes a second inductor, a second resistor, a first RF cutoff capacitor, and a first filter capacitor; the fifth filter circuit includes a second RF cutoff capacitor and a second filter capacitor; one end of the second inductor is connected to the gate power supply, the other end of the second inductor is connected to one end of the second resistor, the other end of the second resistor is connected to the second matching network, and both ends of the first RF cutoff capacitor and the first filter capacitor are respectively connected to the gate power supply and ground; both ends of the second RF cutoff capacitor and the second filter capacitor are respectively connected to the drain power supply and ground.

[0014] Optionally, the radio frequency heating assembly further includes a circuit board, on which the drive amplifier and the final stage amplifier are spaced apart.

[0015] Optionally, the driver amplifier and the final stage amplifier are disposed on the same side of the circuit board, and the circuit board is further provided with an isolation wall between the driver amplifier and the final stage amplifier disposed on the circuit board.

[0016] Optionally, the circuit board also has a heat dissipation structure on the side opposite to the driver amplifier and the final stage amplifier.

[0017] On the other hand, this utility model embodiment provides an aerosol generation device, including the above-mentioned radio frequency heating component, wherein the heating structure includes a resonant cavity for accommodating an aerosol forming matrix, and the radio frequency signal output by the final stage amplifier is transmitted to the resonant cavity to heat the aerosol forming matrix.

[0018] Optionally, the aerosol generator further includes a switch, a circulator, a power coupler, a power detection unit, and a microcontroller. The switch connects the output of the microwave signal source to the input of the driver amplifier. The radio frequency signal output by the final stage amplifier is transmitted to the resonant cavity via the circulator. The reflected signal from the resonant cavity is transmitted to the power coupler via the circulator. The power coupler samples the reflected signal and sends the sampled signal to the power detection unit. The microcontroller controls the microwave signal source, the switch, and the driver amplifier based on the power signal sent by the power detection unit.

[0019] The implementation of this utility model embodiment has the following beneficial effects: The radio frequency heating component includes a microwave signal source, a driver amplifier, a final stage amplifier, and a heating structure. The microwave signal generated by the microwave signal source is amplified sequentially by the driver amplifier and the final stage amplifier and transmitted to the heating structure. The heating structure is used to heat the item to be heated by microwaves. The microwave signal is amplified to a first preset power by the driver amplifier and then amplified to a second preset power by the final stage amplifier. By combining the driver amplifier and the final stage amplifier to form a link design, the power of the radio frequency signal emitted from the microwave signal source is amplified step by step, thereby generating a sufficiently large radio frequency power energy to generate the required heat. The driver amplifier and the final stage amplifier are discrete chips, and the heat generated by the final stage amplifier is dissipated quickly, reducing the impact of the heat generated by the final stage amplifier on the driver amplifier, thereby improving the heat output stability of the radio frequency heating component. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of a radio frequency heating assembly provided in an embodiment of the present invention;

[0021] Figure 2 This is a schematic diagram of the structure of a driver amplifier provided in an embodiment of the present invention;

[0022] Figure 3 This is a circuit diagram of a driver amplifier provided in an embodiment of the present invention;

[0023] Figure 4 This is a schematic diagram of the structure of a final stage amplifier provided in an embodiment of this utility model;

[0024] Figure 5 These are circuit schematics of various fourth filter circuits provided in embodiments of this utility model;

[0025] Figure 6 This is a circuit schematic diagram of a final stage amplifier provided in an embodiment of the present invention;

[0026] Figure 7 This is a side view of a circuit board in a radio frequency heating assembly provided in an embodiment of the present invention;

[0027] Figure 8 This is a top view of a circuit board in a radio frequency heating assembly provided in an embodiment of the present invention;

[0028] Figure 9 This is a schematic diagram of the structure of an aerosol generating device provided in an embodiment of this utility model. Detailed Implementation

[0029] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0030] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion.

[0031] Unless otherwise defined, all technical and scientific terms used in the embodiments of this utility model have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the embodiments of this utility model is for the purpose of describing the embodiments of this application only and is not intended to limit this application.

[0032] See Figure 1 This utility model provides a radio frequency heating component, including a microwave signal source, a driver amplifier, a final stage amplifier, and a heating structure. The microwave signal generated by the microwave signal source is amplified by the driver amplifier and the final stage amplifier in sequence and transmitted to the heating structure. The heating structure is used to heat the item to be heated by microwaves. The microwave signal is amplified to a first preset power by the driver amplifier and then amplified to a second preset power by the final stage amplifier. The driver amplifier and the final stage amplifier are discrete chips.

[0033] A microwave signal source is used to generate radio frequency (RF) signals. The frequency and power of the microwave signal source are determined according to the actual application, and this embodiment does not impose specific limitations. For example, the microwave signal source is usually a phase-locked loop (PLL) signal generator or a voltage-controlled oscillator (VCO), which generates RF signals of 2.4–2.5 GHz according to preset requirements, with very low output power, typically in the range of -5 to 5 dBm.

[0034] The driver amplifier amplifies the signal generated by the microwave signal source to the power level required by the final stage amplifier. The final stage amplifier provides sufficient signal drive capability to ensure that the RF heating component can efficiently and stably output the required RF power to achieve the desired heat.

[0035] The implementation of this utility model embodiment has the following beneficial effects: The radio frequency heating component includes a microwave signal source, a driver amplifier, and a final stage amplifier. The microwave signal generated by the microwave signal source is amplified sequentially by the driver amplifier and the final stage amplifier. The microwave signal is amplified to a first preset power by the driver amplifier and then amplified to a second preset power by the final stage amplifier. By combining the driver amplifier and the final stage amplifier to form a link design, the power of the radio frequency signal emitted from the microwave signal source is amplified step by step, thereby generating a sufficiently large radio frequency power energy to generate the required heat. The driver amplifier and the final stage amplifier are discrete chips, and the heat generated by the final stage amplifier is quickly dissipated, reducing the impact of the heat generated by the final stage amplifier on the driver amplifier, thereby improving the heat output stability of the radio frequency heating component.

[0036] Optionally, the final stage amplifier includes a third-generation semiconductor GaN power amplifier.

[0037] Third-generation GaN power amplifiers utilize third-generation semiconductor technology, consisting of a die and internal matching components, and are packaged in a plastic package. The die employs SiC-based GaN technology; device packaging includes, but is not limited to, various forms of plastic packages such as QFN (QuadFlat No-leads Package), DFN (Dual Flat No-leads Package), and LGA (Land Grid Array).

[0038] Using a third-generation semiconductor GaN power amplifier in the final stage can reduce size and facilitate miniaturization.

[0039] Optionally, the range of the first preset power includes 0.4W to 1W.

[0040] It should be noted that the first preset power is determined based on the actual application, and this embodiment does not impose specific limitations. For example, the minimum output power of the driver amplifier is about 0.4W, and the maximum output power of the driver amplifier can reach about 30dBm (i.e., 1W).

[0041] In some specific embodiments, the driver amplifier may consist of an integrated 2-stage or 3-stage amplifier to enable the driver amplifier to output greater power.

[0042] Optionally, the range of the second preset power is 10W to 30W.

[0043] It should be noted that the second preset power is determined based on the actual application, and this embodiment does not impose specific limitations. The final stage amplifier is used to further amplify the input signal to the power level required by subsequent applications. Depending on the requirements of different products, the range of the second preset power includes, but is not limited to, 10W to 30W.

[0044] Optionally, the driver amplifier includes a first chip, several filter circuits, and a first matching network. The first chip includes several stages of amplification circuits. The power supply of each stage of amplification circuit is connected to the first chip through the filter circuit. The output of the first chip is connected to the final stage amplifier through the first matching network.

[0045] The functions of filtering circuits include, but are not limited to, DC isolation and / or RF cutoff of input signals. Matching networks are used to achieve impedance matching, ensuring efficient signal transmission and minimizing reflections. By adjusting the impedance in the circuit, matching networks enable signals to be smoothly transmitted from one component to another during transmission, reducing signal reflections and losses, thereby improving the efficiency and stability of the circuit.

[0046] It should be noted that the number of amplifier stages included in the first chip is determined based on the actual application, and this embodiment does not impose specific limitations. The specific structure of the filter circuit is determined based on the actual application, and this embodiment does not impose specific limitations. The structure of the filter circuit varies depending on the input power supply.

[0047] Optionally, see Figure 2 The driver amplifier includes a first filter circuit, a second filter circuit, and a third filter circuit. The first chip includes a first-stage amplifier circuit, a second-stage amplifier circuit, and a third-stage amplifier circuit. The input microwave signal is connected to the input port of the first chip through a DC blocking capacitor. The first power supply is connected to the power input port of the first-stage amplifier circuit through the first filter circuit. The second power supply is connected to the power input port of the second-stage amplifier circuit through the second filter circuit. The first matching network is connected to the output port of the first chip and the output port of the driver amplifier. The third power supply is connected to the first matching network through the third filter circuit.

[0048] It should be noted that the sizes of the first, second, and third power supplies are determined based on the actual application, and this embodiment does not impose specific limitations. The microwave signal is isolated from the DC signal or voltage by a DC blocking capacitor, allowing the AC signal to pass through. The DC blocking capacitor reduces the interference of the DC signal on the AC signal, thereby ensuring the normal operation of the circuit and improving its reliability and stability. The first power supply provides voltage to the first-stage amplifier circuit through a first filter circuit for RF blocking and filtering; the second power supply provides voltage to the second-stage amplifier circuit through a second filter circuit for RF blocking and filtering; and the third power supply provides voltage to the third-stage amplifier circuit through a third filter circuit for RF blocking and filtering. The first matching network consists of microstrip lines, capacitors, inductors, etc.

[0049] Optionally, see Figure 3The first filter circuit includes a first resistor R1, a third capacitor C3, and a sixth capacitor C6. One end of the first resistor R1 is connected to the first power supply V1, and the other end of the first resistor R1 is connected to the power input port of the first stage amplifier circuit. The two ends of the third capacitor C3 are connected to one end of the first resistor R1 and ground GND, respectively. The two ends of the sixth capacitor C6 are connected to the other end of the first resistor R1 and ground GND, respectively. The third capacitor C3 is used for filtering, the sixth capacitor C6 is used for radio frequency blocking, and the first resistor R1 can improve power supply stability.

[0050] The second filter circuit includes a first capacitor C1 and a fourth capacitor C4. The two ends of the first capacitor C1 and the fourth capacitor C4 are respectively connected to the second power supply V2 and the ground GND. The first capacitor C1 is used for filtering, and the fourth capacitor C4 is used for radio frequency blocking.

[0051] The third filter circuit includes a second capacitor C2, a fifth capacitor C5, and a first inductor L1. One end of the first inductor L1 is connected to the third power supply V3, and the other end of the first inductor L1 is connected to the first matching network. The two ends of the second capacitor C2 and the fifth capacitor C5 are respectively connected to the third power supply V3 and the ground GND. The first inductor L1 and the fifth capacitor C5 are used for radio frequency blocking, and the second capacitor C2 is used for filtering.

[0052] Specifically, see Figure 3 The first chip also includes an enable port pin, a ground port pin, and other power supply port pins. The microwave signal SG is connected to the signal input port pin of the first chip through a DC blocking capacitor C8. The power supply VDD is filtered by capacitor C13 and then connected to the enable port pin. The power supply VDD is filtered by capacitor C14 and then connected to the bias voltage port pin. The first matching network consists of microstrip lines, capacitors, inductors, etc. The seventh capacitor C7 and the twelfth capacitor C12 are connected to the microstrip line and ground respectively. The ninth capacitor C9 is connected in series with the inductor L2 and then connected to the end of the microstrip line. One end of the tenth capacitor C10 is connected to one end of the inductor L2 and ground. One end of the eleventh capacitor C11 is connected to the other end of the inductor L2 and ground. The output of the first matching network is the output signal SGOUT.

[0053] Optionally, see Figure 4 The final stage amplifier includes a second matching network, a GaN power amplifier, a third matching network, a fourth filter circuit, and a fifth filter circuit. The microwave signal output from the final stage amplifier drives the amplifier and serves as the input microwave signal to the second matching network. The input microwave signal is connected to the gate port of the GaN power amplifier through the second matching network. The gate power supply is connected to the second matching network through the fourth filter circuit. The drain port of the GaN power amplifier is connected to the output port of the final stage amplifier through the third matching network. The drain power supply is connected to the third matching network through the fifth filter circuit.

[0054] It should be noted that the fourth and fifth filter circuits are determined based on the actual application, and this embodiment does not impose specific limitations. The fourth filter circuit includes various combinations of capacitors, resistors, and inductors, and the fifth filter circuit includes several capacitors. The input signal can be connected to the second matching network through a DC blocking capacitor, and the third matching network is connected to the output port through a DC blocking capacitor.

[0055] In one specific embodiment, see Figure 5 RFIN represents the input signal, see [link / reference] Figure 5 It includes three different fourth filter circuits. C21 / C23 / C25 represent DC blocking capacitors. Figure 5 The fourth filter circuit in (a) includes a resistor R11 and a capacitor C22. The resistor R11 is connected to the gate power supply and the second matching network, and the capacitor C22 is connected to the gate power supply and ground. Figure 5 The fourth filter circuit in (b) includes a resistor R12, an inductor L11 and a capacitor C24. The resistor R12 and the inductor L11 are connected in series. The other end of the resistor R12 is connected to the second matching network. The other end of the inductor L11 is connected to the gate power supply. The capacitor C24 is connected to the gate power supply and ground. Figure 5 The fourth filter circuit in (c) includes a resistor R13, an inductor L12, and capacitors C26 / C27. The resistor R13 and the inductor L12 are connected in series. The other end of the resistor R13 is connected to the second matching network, the other end of the inductor L12 is connected to the gate power supply, and the capacitors C26 / C27 are connected to the gate power supply and ground respectively.

[0056] The second and third matching networks optimize impedance to improve efficiency and bandwidth, while using appropriate bias to ensure stable device operation. The second and third matching networks achieve optimal performance within the desired frequency band, with performance parameters including, but not limited to, output power, gain flatness, and efficiency.

[0057] Using GaN HEMT (High Electron Mobility Transistor) as the core, a two-dimensional electron gas is formed by AlGaN / GaN heterojunction to achieve high current density and high operating voltage. By controlling the electron density in the channel through the gate, linear amplification of the signal is achieved.

[0058] Optionally, see Figure 6 The fourth filter circuit includes a second inductor L2, a second resistor R22, a first RF cutoff capacitor C31, and a first filter capacitor C32. One end of the second inductor L2 is connected to the gate power supply Vgate, and the other end of the second inductor L2 is connected to one end of the second resistor R22. The other end of the second resistor R22 is connected to the second matching network. The two ends of the first RF cutoff capacitor C31 and the first filter capacitor C32 are respectively connected to the gate power supply Vgate and ground.

[0059] The fifth filter circuit includes a second RF cutoff capacitor C34 and a second filter capacitor C33; the two ends of the second RF cutoff capacitor C34 and the second filter capacitor C33 are respectively connected to the drain power supply Vdrain and the ground terminal.

[0060] Specifically, see Figure 6 PA_IN represents the input signal, PA_OUT represents the output signal, capacitors C35 / C36 are DC blocking capacitors, capacitors C37 / C38 form a second matching network with the microstrip line, and capacitors C39 / C40 form a third matching network with the microstrip line.

[0061] Referring to Table 1, in a specific embodiment, the microwave signal source input power (2.50dBm / 0W) is amplified through multiple stages of a driver amplifier, interstage matching network, and final stage amplifier, reaching a power of (44.05dBm / 25.41W) at the circulator. The amplification power of the driver amplifier and interstage matching network is relatively small, while the amplification power of the final stage amplifier is relatively large.

[0062] Table 1

[0063]

[0064] Optionally, the radio frequency heating assembly also includes a circuit board on which the driver amplifier and the final stage amplifier are spaced apart.

[0065] See Figure 7 , Figure 7 This is a side view of the circuit board in the radio frequency heating assembly. The radio frequency heating assembly includes a circuit board 40, on which a driver amplifier 10 and a final stage amplifier 20 are spaced apart. There is sufficient space between them to reduce the influence of the final stage amplifier on the driver amplifier and to accelerate the heat dissipation.

[0066] Optionally, the driver amplifier and the final stage amplifier are located on the same side of the circuit board, and the circuit board is also provided with an isolation wall between the driver amplifier and the final stage amplifier.

[0067] See Figure 8 , Figure 8 This diagram shows a top view of the circuit board in the RF heating assembly. The driver amplifier 10 and the final stage amplifier 20 are located on the same side of the circuit board 30, and a shielding wall 50 is provided between the driver amplifier 10 and the final stage amplifier 20. Placing a shielding wall directly in the area where the driver amplifier and final stage amplifier are located reduces self-excitation, increases system stability, and lowers EMC / EMI risks. As an example, the shielding wall 50 can be a metal coating formed on the circuit board.

[0068] Optionally, the circuit board also has a heat dissipation structure on the side opposite to the driver amplifier and the final stage amplifier. That is, the heat dissipation structure and the driver amplifier are located on opposite sides of the circuit board, and the heat dissipation structure and the final stage amplifier are located on opposite sides of the circuit board, wherein the driver amplifier and the final stage amplifier are located on the same side of the circuit board.

[0069] See Figure 7 The circuit board 10 also has a heat dissipation structure 40 on the same side of the circuit board away from the driver amplifier 10 and the final stage amplifier 20. The heat dissipation structure 40 can serve as a heat dissipation channel to further accelerate the heat dissipation of the final stage amplifier and reduce the direct conduction of heat from the final stage amplifier to the driver amplifier. Specifically, the heat dissipation structure 40 can be a metal component made of metal materials, such as an aluminum metal plate.

[0070] This utility model provides an aerosol generation device, including the above-mentioned radio frequency heating component, wherein the heating structure includes a resonant cavity for accommodating the aerosol forming matrix, and the radio frequency signal output by the final stage amplifier is transmitted to the resonant cavity to heat the aerosol forming matrix.

[0071] As an example, the heating structure can refer to a metal outer conductor made of metallic material and defining a receiving cavity, such as a cylinder open at one end and closed at the other. Furthermore, the outer conductor may contain an inner conductor in ohmic contact with the inner conductor. Other structural forms are also possible, but not limited to these; other structures based on existing technology can be used. The aforementioned object to be heated includes, but is not limited to, solid tobacco, tobacco paste, and tobacco liquid.

[0072] Optionally, the aerosol generator further includes a switch, a circulator, a power coupler, a power detection unit, and a microcontroller. The switch connects the output of the microwave signal source to the input of the driver amplifier. The radio frequency signal output from the final stage amplifier is transmitted to the resonant cavity via the circulator. The reflected signal from the resonant cavity is transmitted to the power coupler via the circulator. The power coupler samples the reflected signal and sends the sampled signal to the power detection unit. The microcontroller controls the microwave signal source, the switch, and the driver amplifier based on the power signal sent by the power detection unit.

[0073] See Figure 9 This utility model provides an aerosol generating device, including the above-mentioned radio frequency heating component, as well as a switch, a circulator, a power coupler, a power detection unit, a microcontroller, and a resonant cavity. The switch is connected to the output terminal of the microwave signal source and the input terminal of the driver amplifier. The radio frequency signal output by the final stage amplifier is transmitted to the resonant cavity through the circulator. The reflected signal from the resonant cavity is transmitted to the power coupler through the circulator. The power coupler samples the reflected signal and sends the sampled signal to the power detection unit. The microcontroller controls the microwave signal source, the switch, and the driver amplifier according to the power signal sent by the power detection unit.

[0074] It should be noted that the input terminal of the switch is connected to the microwave signal source to control the signal transmission on and off, and to control the output mode, such as continuous output or pulse modulation output mode, and also serves as an emergency protection mechanism. The output terminal of the switch is connected to a driver amplifier to receive the RF signal from the switch and amplify it at a medium power level. The driver amplifier is a multi-stage amplifier that amplifies the small signal from the microwave signal source to a level sufficient to drive the final stage amplifier. The output terminal of the driver amplifier is connected to the input terminal of the final stage amplifier. The amplified RF signal from the driver amplifier is transmitted to the resonant cavity via a circulator, with a portion of the RF signal returning to the circulator. The circulator strips the signal reflected back from the resonant cavity and transmits it to a power coupler. The power coupler samples a suitable amount of the reflected RF signal, and after passing through a power detection unit, obtains the RF power and sends it to the microcontroller so that the microcontroller can control the microwave signal source, the switch, and the driver amplifier.

[0075] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0076] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between apparatuses or units through some interfaces, and may be electrical, mechanical, or other forms.

[0077] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0078] The above is a detailed description of the preferred embodiments of the present utility model. However, the present utility model is not limited to the described embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present utility model. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.

Claims

1. A radio frequency heating assembly, characterized by, The microwave signal source, the push amplifier, the final amplifier and the heating structure, wherein: the microwave signal generated by the microwave signal source is amplified by the push amplifier and the final amplifier in turn and transmitted to the heating structure, the heating structure is used for heating the goods to be heated by microwave, the microwave signal is amplified to the first preset power by the push amplifier and the second preset power by the final amplifier, and the push amplifier and the final amplifier are discrete chips.

2. The radio frequency heating assembly of claim 1, wherein, The final amplifier comprises a third generation semiconductor GaN power amplifier.

3. The radio frequency heating assembly of claim 1, wherein, The first preset power ranges from 0.4W to 1W.

4. The radio frequency heating assembly of claim 1, wherein, The second preset power ranges from 10W to 30W.

5. The radio frequency heating assembly of claim 1, wherein, The push amplifier comprises a first chip, a plurality of filter circuits and a first matching network, the first chip comprises a plurality of amplification circuits, the power supply of each amplification circuit is connected to the first chip through the filter circuit, and the output of the first chip is connected to the final amplifier through the first matching network.

6. The radio frequency heating assembly of claim 5, wherein, The push amplifier comprises a first filter circuit, a second filter circuit and a third filter circuit, the first chip comprises a first amplification circuit, a second amplification circuit and a third amplification circuit, the input microwave signal is connected to the input port of the first chip through a direct current blocking capacitor, a first power supply is connected to the power input port of the first amplification circuit through the first filter circuit, a second power supply is connected to the power input port of the second amplification circuit through the second filter circuit, the first matching network is connected to the output port of the first chip and the output port of the push amplifier, and a third power supply is connected to the first matching network through the third filter circuit.

7. The radio frequency heating assembly of claim 6, wherein, The first filter circuit comprises a first resistor, a third capacitor and a sixth capacitor, the second filter circuit comprises a first capacitor and a fourth capacitor, and the third filter circuit comprises a second capacitor, a fifth capacitor and a first inductor; one end of the first resistor is connected to the first power supply, the other end of the first resistor is connected to the power input port of the first amplification circuit, two ends of the third capacitor are respectively connected to one end of the first resistor and a ground terminal, and two ends of the sixth capacitor are respectively connected to the other end of the first resistor and the ground terminal; two ends of the first capacitor and the fourth capacitor are respectively connected to the second power supply and the ground terminal; one end of the first inductor is connected to the third power supply, the other end of the first inductor is connected to the first matching network, and two ends of the second capacitor and the fifth capacitor are respectively connected to the third power supply and the ground terminal.

8. The radio frequency heating assembly of claim 1, wherein, The final amplifier comprises a second matching network, a GaN power amplifier, a third matching network, a fourth filter circuit and a fifth filter circuit, the input microwave signal is connected to the gate port of the GaN power amplifier through the second matching network, a gate power supply is connected to the second matching network through the fourth filter circuit, the drain port of the GaN power amplifier is connected to the output port of the final amplifier through the third matching network, and a drain power supply is connected to the third matching network through the fifth filter circuit.

9. The radio frequency heating assembly of claim 8, wherein, The fourth filter circuit comprises a second inductor, a second resistor, a first radio frequency cutoff capacitor and a first filter capacitor, and the fifth filter circuit comprises a second radio frequency cutoff capacitor and a second filter capacitor; one end of the second inductor is connected to the gate power supply, the other end of the second inductor is connected to one end of the second resistor, the other end of the second resistor is connected to the second matching network, and both ends of the first radio frequency cutoff capacitor and the first filter capacitor are respectively connected to the gate power supply and the ground end; both ends of the second radio frequency cutoff capacitor and the second filter capacitor are respectively connected to the drain power supply and the ground end.

10. The radio frequency heating assembly of any one of claims 1 to 9, wherein, The radio frequency heating assembly further comprises a circuit board, and the push amplifier and the final-stage amplifier are arranged on the circuit board.

11. The radio frequency heating assembly of claim 10, wherein, The push amplifier and the final-stage amplifier are arranged on the same side of the circuit board, and the circuit board is further provided with an isolation wall between the push amplifier and the final-stage amplifier.

12. The radio frequency heating assembly of claim 11, wherein, The circuit board is further provided with a heat dissipation structure on the other side away from the push amplifier and the final-stage amplifier.

13. An aerosol-generating device comprising: The radio frequency heating assembly comprises a heating structure, and the push amplifier and the final-stage amplifier are arranged on the circuit board.

14. The aerosol-generating device of claim 13, wherein, The radio frequency heating assembly further comprises a switch, a circulator, a power coupler, a power detection unit and a microcontroller. The switch is connected to the output end of the microwave signal source and the input end of the push amplifier. The radio frequency signal output by the final-stage amplifier is transmitted to the resonant cavity through the circulator. The reflected signal of the resonant cavity is transmitted to the power coupler through the circulator. The power coupler samples the reflected signal and sends the sampled signal to the power detection unit. The microcontroller controls the microwave signal source, the switch and the push amplifier according to the power signal sent by the power detection unit.

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