Radio frequency power supply and inverter protection circuit thereof
By incorporating protection circuits, including switching modules and limiting protection circuits, into the inverter of the RF power supply, the problems of load instability and equipment damage caused by excessive RF power supply output current are solved, thereby improving the stability and safety of the equipment.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-21
- Publication Date
- 2026-03-20
AI Technical Summary
Existing RF power supplies may cause load instability or equipment damage when the output current is too high.
A protection circuit is set between the local oscillator signal circuit and the bridge switching circuit of the inverter, including a switching module, a first operational amplifier, a first voltage distribution module, an energy storage component, and a limiting protection circuit module. By comparing the output signal of the RF power supply with the limit signal, the switching module is controlled to disconnect to avoid excessively high output signals, and the voltage is limited to a safe range by the limiting protection circuit.
This effectively avoids damage to the load caused by excessively high output signals from the RF power supply, thus improving the stability and safety of the equipment.
Smart Images
Figure CN224021633U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to the technical field of radio frequency power supply equipment, specifically relates to a radio frequency power supply and inverter protection circuit thereof. BACKGROUND
[0002] Radio frequency power supply and its inverter have wide application in many industrial and scientific research fields, especially in the fields of semiconductor manufacturing, plasma processing, material processing and the like. The inverter is one of the core components in the radio frequency power supply, responsible for converting stable direct current into adjustable radio frequency alternating current. By controlling the switching frequency and duty cycle of the inverter, the frequency and amplitude of the output radio frequency signal can be adjusted.
[0003] When the output current of the radio frequency power supply is too high, sensitive load devices connected to the radio frequency power supply, such as plasma reaction chambers, may cause unstable plasma or produce unnecessary by-products, and even cause damage to the equipment due to the excessively high current. SUMMARY
[0004] The technical problem to be solved by the utility model is to overcome the defect that the output current of the radio frequency power supply in the prior art may cause unstable operation of the load or even damage to the equipment, thereby providing a radio frequency power supply and an inverter protection circuit thereof.
[0005] The utility model discloses an inverter protection circuit of radio frequency power supply sets up between the local oscillator signal circuit of control the inverter and bridge type switch circuit, its characterized in being, the protection circuit of inverter includes switching module, first operational amplifier, first pressure distribution module, energy storage component and the limiting amplitude protection circuit module of the first pressure distribution module;
[0006] The input end of the switching module is connected to the local oscillator signal circuit, and the output end controls the pass and break of the latch circuit. The latch circuit is arranged between the drive circuit of the inverter and the bridge type switch circuit.
[0007] The first pressure distribution module adjusts the first direct current source to form a first limiting signal.
[0008] The energy storage component converts the output signal of the radio frequency power supply to form an input signal.
[0009] The first non-inverting input end of the first operational amplifier obtains the input signal, the first inverting input end obtains the first limiting signal, and the first output end is connected to the control end of the switching module. According to the comparison result of the input signal and the first limiting signal, the pass and break of the switching module are controlled.
[0010] The amplitude limiting protection circuit module is connected in parallel with the first voltage distribution module and is arranged between the first DC power source and the ground, and a potential clamping node of the amplitude limiting protection circuit module is electrically connected between the first non-inverting input terminal and the energy storage component.
[0011] Further, the second operational amplifier and the second voltage distribution module are further included.
[0012] The second voltage distribution module adjusts a second DC power source to form a second limiting signal.
[0013] The second non-inverting input terminal of the second operational amplifier obtains the input signal, the second inverting input terminal obtains the second limiting signal, and a pre-warning signal of high or low is output according to the comparison between the input signal and the second limiting signal.
[0014] Further, the first DC power source and the second DC power source are the same DC power source, and the amplitude limiting protection circuit module and the second voltage distribution module are arranged in parallel.
[0015] Further, the amplitude limiting protection circuit module includes a first diode and a second diode connected in series in the same conduction direction, the cathode of the first diode is connected to the first DC power source, the anode of the second diode is connected to the ground, and the potential clamping node between the first diode and the second diode is connected between the first non-inverting input terminal and the energy storage component.
[0016] Further, the energy storage component is an energy storage capacitor, which is charged and boosted by the output current of the RF power source to form the input signal.
[0017] Further, the switching module is a relay.
[0018] Further, the switching module includes a first AND gate and a NOT gate, the first input terminal of the first AND gate is connected to the local oscillator signal circuit, the output terminal is connected to the latch circuit of the bridge switch circuit, the second input terminal of the first AND gate is connected to the output terminal of the NOT gate, and the input terminal of the NOT gate is connected to the first output terminal.
[0019] Further, the latch circuit is one or more than one second AND gate arranged in parallel, the first input terminal of the second AND gate is connected to the output terminal of the driving circuit, the output terminal is connected to the control terminal of the switch tube of the bridge switch circuit, and the second input terminal is connected to the output terminal of the switching module.
[0020] Further, the latch circuit is one or more than one relay arranged in parallel, the input terminal of the relay is connected to the output terminal of the driving circuit, the output terminal is connected to the control terminal of the switch tube of the bridge switch circuit, and the control terminal is connected to the output terminal of the switching module.
[0021] An inverter of a radio frequency power supply, the inverter comprises a local signal circuit, a driving circuit, a latch circuit, a bridge switch circuit and a protection circuit as described above;
[0022] The driving circuit is electrically coupled to the control end of the switch tube of the bridge switch circuit to switch on and off the switch tube.
[0023] The latch circuit is arranged between the driving circuit and the bridge switch circuit and is electrically coupled to the local signal circuit and controlled by the local signal circuit to switch the path and the circuit between the driving circuit and the bridge switch circuit.
[0024] The protection circuit is electrically coupled between the local signal circuit and the latch circuit and controls the on-off between the local signal circuit and the latch circuit according to the input signal formed by the energy storage component.
[0025] Further, the protection circuit is arranged in pairs with the local signal circuit; the local signal circuit is multiple, and the switching module of the protection circuit is the same as the number of the local signal circuit and arranged in pairs.
[0026] Further, the protection circuit is arranged in pairs with the local signal circuit; the local signal circuit is multiple, and the switching module of the protection circuit is the same as the number of the local signal circuit and arranged in pairs.
[0027] Beneficial effects: the utility model discloses a radio frequency power supply and its inverter protection circuit, and the protection circuit is arranged between the local signal circuit and the bridge switch circuit of control inverter, including switching module, first operational amplifier, first voltage distribution module, energy storage component and the limiting amplitude protection circuit module, the output signal of radio frequency power supply is obtained through energy storage component, and when the output signal of radio frequency power supply is greater than the preset threshold value, the connection of local signal circuit and bridge switch circuit is cut off through switching module, thereby avoiding that the high output signal of radio frequency power supply is output to the load, and avoiding equipment overload damage, and the utility model restricts voltage in the safe range through limiting amplitude protection circuit module, and the stability of protection circuit is further improved. BRIEF DESCRIPTION OF DRAWINGS
[0028] In order to more clearly illustrate the technical scheme in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiment or the prior art description will be briefly introduced below, and obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creating labor.
[0029] Figure 1 It is a schematic block diagram of the overall structure of the utility model.
[0030] Figure 2 A protection circuit schematic diagram of the utility model;
[0031] Figure 3 A schematic block diagram of another inverter structure of the utility model;
[0032] Figure 4 A schematic block diagram of another inverter structure of the utility model.
[0033] Legend:
[0034] 1, first pressure distribution module; 2, second pressure distribution module; 3, limiting amplitude protection circuit module; 4, switching module; 5, latch circuit; 6, bridge switch circuit; 7, drive circuit; 8, local oscillator signal circuit; 9, energy storage component; 10, protection circuit;
[0035] R1, input resistor; R2, second resistor; R3, third resistor; R4, fourth resistor; R5, fifth resistor; R6, sixth resistor; R7, seventh resistor; C1, energy storage capacitor; C2, second capacitor; C3, third capacitor; D1, first diode; D2, second diode; U1, first operational amplifier; U2, second operational amplifier; U3, NOT gate; U4, first AND gate; U5, second AND gate; VCC1, first DC source; VCC2, second DC source; VCC3, third DC source; VCC4, fourth DC source. DETAILED DESCRIPTION
[0036] In order to make the above objects, features and advantages of the present application more apparent, specific embodiments of the present application are described in detail below with reference to the accompanying drawings. In the following description, a large number of specific details are set forth in order to provide a sufficient understanding of the present application. However, the present application can be implemented in many different ways from those described herein, and those skilled in the art can make similar improvements without departing from the spirit of the present application, so the present application is not limited to the specific embodiments disclosed below.
[0037] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.
[0038] In addition, the terms "first", "second", etc. are used only for descriptive purposes and should not be construed as indicating or implying relative importance or an indicated number of technical features. Therefore, the features defined as "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise explicitly specified and limited.
[0039] In this application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection", "fixing" and other terms should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrated; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium, it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise explicitly limited. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.
[0040] Embodiment one:
[0041] Referring to Figure 1 and Figure 2 The embodiment provides an inverter protection circuit 10 of a radio frequency power supply, which is arranged between a local oscillator signal circuit 7 for controlling the inverter and a bridge switch circuit 6, and characterized in that the inverter protection circuit 10 comprises a switching module 4, a first operational amplifier U1, a first voltage distribution module 1, an energy storage component 9 and a limiting protection circuit module 3; the input end of the switching module 4 is connected to the local oscillator signal circuit 7, and the output end controls the on-off path of a latch circuit 5, which is arranged between a driving circuit 10 of the inverter and the bridge switch circuit 6; the first voltage distribution module 1 adjusts a first direct current source VCC1 to form a first limiting signal; the energy storage component 9 converts a radio frequency power supply output signal to form an input signal; the first non-inverting input end of the first operational amplifier U1 obtains the input signal, the first inverting input end obtains the first limiting signal, and the first output end is connected to the control end of the switching module 4, so as to control the on-off path of the switching module 4 according to the comparison result of the input signal and the first limiting signal; the limiting protection circuit module 3 is connected in parallel with the first voltage distribution module 1 and arranged between the first direct current source VCC1 and the ground, and the potential clamping node of the limiting protection circuit module 3 is electrically connected between the first non-inverting input end and the energy storage component 9.
[0042] The output signal of the radio frequency power supply is obtained by the energy storage component 9, and is compared by the first voltage distribution module 1 and the first operational amplifier U1, when the output signal of the radio frequency power supply is greater than a preset threshold, the connection between the local oscillator signal circuit 7 and the bridge type switch circuit 6 is cut off by the switching module 4, so that the high output signal of the radio frequency power supply is prevented from being output to the load, and the equipment is prevented from being damaged due to overload; meanwhile, the voltage is limited in a safe range by the limiting amplitude protection circuit module 3, and the stability of the protection circuit 9 is further improved.
[0043] Specifically, the first non-inverting input terminal of the first operational amplifier U1 obtains the input signal through the second resistor R2, the first voltage distribution module 1 comprises a third resistor R3 and a fourth resistor R4, the first inverting input terminal of the first operational amplifier U1 is connected with the first end of the third resistor R3 and the fourth resistor R4 respectively, the second end of the third resistor R3 is connected with a direct current source, and the second end of the fourth resistor R4 is grounded. The positive power supply end of the first operational amplifier U1 is connected with a third direct current source VCC3 and grounded through a second capacitor C2, and the negative power supply end of the first operational amplifier U1 is grounded.
[0044] The limiting amplitude protection circuit module 3 comprises a first diode D1 and a second diode D2 connected in series in the same conduction direction, the cathode of the first diode D1 is connected with a first direct current source VCC1, the anode of the second diode D2 is connected with the ground, and the potential clamping node between the first diode D1 and the second diode D2 is connected between the first non-inverting input terminal and the energy storage component 9.
[0045] In the embodiment, the energy storage component 9 is an energy storage capacitor C1, which is charged and boosted by the output current of the radio frequency power supply to form the input signal. The input resistor R1 is also included, the first end of the input resistor R1 is connected with the output signal of the radio frequency power supply, the second end is connected with the first end of the energy storage capacitor C1, and the second end of the energy storage capacitor C1 is grounded. The first end of the energy storage capacitor C1 forms the input signal.
[0046] In some embodiments of the embodiment, the switching module 4 is a relay, which is denoted as a first relay.
[0047] In the embodiments, the latch circuit 5 comprises one or more than one parallelly arranged relays, which are denoted as second relays, the input end of the second relay is connected with the output end of the driving circuit 7, the output end is connected with the control end of the switch tube of the bridge type switch circuit 6, and the control end is connected with the output end of the switching module 4.
[0048] In some other embodiments of the present embodiment, the switching module ④ comprises a first AND gate U4 and a NOT gate U3, the first input terminal of the first AND gate U4 is connected to the local oscillator signal circuit ⑧, the output terminal is connected to the latch circuit ⑤ of the bridge switch circuit ⑥, the second input terminal of the first AND gate U4 is connected to the output terminal of the NOT gate U3, and the first output terminal is connected to the input terminal of the NOT gate U3.
[0049] In the present embodiment, the latch circuit ⑤ comprises a plurality of second AND gates U5 arranged in parallel, the first input terminal of the second AND gate U5 is connected to the output terminal of the driving circuit ⑦, the output terminal is connected to the control terminal of the switch tube of the bridge switch circuit ⑥, and the second input terminal is connected to the output terminal of the switching module ④.
[0050] Embodiment two:
[0051] Referring to Figure 2 Fig. 10 shows an inverter protection circuit ⑩ of a radio frequency power supply according to the present embodiment, which comprises a second operational amplifier U2 and a second voltage distribution module ② in addition to the structure of the protection circuit ⑩ of embodiment one; the second voltage distribution module ② adjusts the second DC source VCC2 to form a second limiting signal; the second same-phase input terminal of the second operational amplifier U2 obtains an input signal, the second opposite-phase input terminal obtains the second limiting signal, and a pre-warning signal of high or low level is output according to the comparison between the input signal and the second limiting signal.
[0052] In the present embodiment, the second limiting signal is greater than the first limiting signal.
[0053] In the present embodiment, the first DC source VCC1 and the second DC source VCC2 are the same DC source, and the amplitude limiting protection circuit module ③ and the second voltage distribution module ② are arranged in parallel. Specifically, the second same-phase input terminal of the second operational amplifier U2 obtains an input signal through the fifth resistor R5, the second voltage distribution module ② comprises a sixth resistor R6 and a seventh resistor R7, the second opposite-phase input terminal of the second operational amplifier U2 is connected to the first terminal of the sixth resistor R6 and the seventh resistor R7 respectively, the second terminal of the sixth resistor R6 is connected to the DC source, and the second terminal of the seventh resistor R7 is grounded. The positive power supply terminal of the second operational amplifier U2 is connected to the fourth DC source VCC4 and grounded through the third capacitor C3, and the negative power supply terminal is grounded.
[0054] Specifically, when the input signal is less than the first limit signal, the first operational amplifier U1 outputs a low bit and the NOT gate U3 outputs a high bit, so the first AND gate U4 or the second AND gate U5 follows the output of the local oscillator signal circuit ⑧, and the inverter works normally under the control of the local oscillator signal circuit ⑧; when the input signal is greater than the first limit signal, the first operational amplifier U1 outputs a high bit and the NOT gate U3 outputs a low bit, so the first AND gate U4 or the second AND gate U5 outputs a low bit, and the inverter stops working; when the input signal is greater than the second limit signal, the second operational amplifier U2 outputs a high bit as a warning signal; when the input signal is less than the second limit signal, the second operational amplifier U2 outputs a low bit as a normal operation signal.
[0055] Example 3:
[0056] Reference Figure 3 and Figure 4 As shown, this embodiment provides an inverter for a radio frequency power supply. The inverter includes a local oscillator signal circuit ⑧, a drive circuit ⑦, a latch circuit ⑤, a bridge switch circuit ⑥, and a protection circuit ⑩ as in Embodiment 1 or Embodiment 2. The drive circuit ⑦ is electrically coupled to the control terminal of the switching transistor of the bridge switch circuit ⑥ to switch the switching transistor on and off. The latch circuit ⑤ is disposed between the drive circuit ⑦ and the bridge switch circuit ⑥ and is electrically coupled to the local oscillator signal circuit ⑧. It is controlled by the local oscillator signal circuit ⑧ to switch the connection and disconnection between the drive circuit ⑦ and the bridge switch circuit ⑥. The protection circuit ⑩ is electrically coupled between the local oscillator signal circuit ⑧ and the latch circuit ⑤, and controls the connection and disconnection between the local oscillator signal circuit ⑧ and the latch circuit ⑤ based on the input signal generated by the energy storage component ⑨.
[0057] Reference Figure 3 As shown, in some embodiments of this example, the protection circuit ⑩ is configured as follows: it is paired with the local oscillator signal circuit ⑧; there are multiple local oscillator signal circuits ⑧, and the switching module ④ of the protection circuit ⑩ is the same number as the local oscillator signal circuit ⑧ and is configured in pairs.
[0058] Reference Figure 4 As shown, in some other embodiments of this example, the protection circuit ⑩ is configured as follows: there are multiple protection circuits ⑩ or their switching modules ④, and they are configured in a one-to-many relationship with the local oscillator signal circuit ⑧.
[0059] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0060] The above embodiments only express several implementation ways of the present application, and the description is specific and detailed, but it should not be understood as a limitation to the patent scope of the application. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, several modifications and improvements can be made, which all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.
Claims
1. An inverter protection circuit for an radio frequency power supply, disposed between the local oscillator signal circuit controlling the inverter and the bridge switching circuit, characterized in that, The inverter's protection circuit includes a switching module, a first operational amplifier, a first voltage distribution module, an energy storage component, and a limiting protection circuit module. The input terminal of the switching module is connected to the local oscillator signal circuit, and the output terminal controls the opening and closing of the latch circuit. The latch circuit is configured between the inverter's drive circuit and the bridge switching circuit. The first voltage distribution module adjusts the first DC source to generate a first limit signal; The energy storage component converts the radio frequency power output signal into an input signal; The first non-inverting input terminal of the first operational amplifier acquires the input signal, the first inverting input terminal acquires the first limit signal, and the first output terminal is connected to the control terminal of the switching module. The switching module is controlled to open and close based on the comparison result between the input signal and the first limit signal. The limiting protection circuit module is connected in parallel with the first voltage distribution module and configured between the first DC source and ground. The potential clamping node of the limiting protection circuit module is electrically connected between the first in-phase input terminal and the energy storage component.
2. The inverter protection circuit for an RF power supply according to claim 1, characterized in that, It also includes a second operational amplifier and a second voltage distribution module; The second voltage distribution module adjusts the second DC source to generate a second limit signal; The second non-inverting input terminal of the second operational amplifier acquires the input signal, and the second inverting input terminal acquires the second limit signal. Based on the comparison between the input signal and the second limit signal, a high-level or low-level warning signal is output.
3. The inverter protection circuit for an RF power supply according to claim 2, characterized in that, The first DC source and the second DC source are the same DC source, and the limiting protection circuit module is connected in parallel with the second voltage distribution module.
4. The inverter protection circuit for an RF power supply according to claim 1, characterized in that, The limiting protection circuit module includes a first diode and a second diode connected in series in the same conduction direction. The cathode of the first diode is connected to the first DC source, and the anode of the second diode is connected to the ground. The potential clamping node between the first diode and the second diode is connected between the first in-phase input terminal and the energy storage component.
5. The inverter protection circuit for an RF power supply according to claim 1, characterized in that, The energy storage component is an energy storage capacitor, which is charged and boosted by the output current of the radio frequency power supply to form the input signal.
6. The inverter protection circuit for an RF power supply according to claim 1, characterized in that, The switching module is a relay.
7. The inverter protection circuit for an RF power supply according to claim 1, characterized in that, The switching module includes a first AND gate and a NOT gate. The first input terminal of the first AND gate is connected to the local oscillator signal circuit, and the output terminal is connected to the latch circuit of the bridge switch circuit. The second input terminal of the first AND gate is connected to the output terminal of the NOT gate, and the input terminal of the NOT gate is connected to the first output terminal.
8. The inverter protection circuit for an RF power supply according to claim 1, characterized in that, The latch circuit consists of one or more second AND gates arranged in parallel. The first input terminal of the second AND gate is connected to the output terminal of the drive circuit, the output terminal is connected to the control terminal of the switching transistor of the bridge switch circuit, and the second input terminal is connected to the output terminal of the switching module.
9. The inverter protection circuit for an RF power supply according to claim 1, characterized in that, The latch circuit consists of one or more relays arranged in parallel. The input terminal of each relay is connected to the output terminal of the drive circuit, the output terminal is connected to the control terminal of the switching transistor of the bridge switch circuit, and the control terminal is connected to the output terminal of the switching module.
10. A radio frequency power supply, characterized in that, The inverter includes a local oscillator signal circuit, a drive circuit, a latch circuit, a bridge switch circuit, and a protection circuit as described in any one of claims 1 to 9; The driving circuit is electrically coupled to the control terminal of the switching transistor of the bridge switching circuit to switch the switching transistor on and off. The latch circuit is configured between the drive circuit and the bridge switch circuit and is electrically coupled to the local oscillator signal circuit, and is controlled by the local oscillator signal circuit to switch the path and open circuit between the drive circuit and the bridge switch circuit; The protection circuit is electrically coupled between the local oscillator signal circuit and the latch circuit, and controls the on / off connection between the local oscillator signal circuit and the latch circuit based on the input signal generated by the energy storage component.
11. A radio frequency power supply according to claim 10, characterized in that, The protection circuit is configured in pairs with the local oscillator signal circuit; there are multiple local oscillator signal circuits, and the number of switching modules of the protection circuit is the same as that of the local oscillator signal circuits and they are configured in pairs.
12. The radio frequency power supply according to claim 10, characterized in that, The protection circuit is configured in such a way that there are multiple protection circuits or their switching modules, and there is a one-to-many configuration relationship between the protection circuit and the local oscillator signal circuit.