Power supplies, magnetic core transformers and printed circuit boards

Abstract

To provide a small transformer and a power supply including the small transformer while maintaining a transformer factor.SOLUTION: A power supply is provided which includes: an RF power source; a magnetic core transformer including a first transformer and a second transformer which boost an output of the RF power source; DC decoupling capacitors connected between a ground and a first terminal of respective output terminals of the first and second transformers; variable capacitors connected between the ground and a second terminal of the respective output terminals of the first and second transformers; a DC power source to provide a DC voltage to the first terminal; and an output terminal to output the DC voltage and a boosted RF voltage. Each of the first and second transformers includes an input coil, a magnetic core, and an output coil. The input coil includes an outer winding and an inner winding. The outer winding and the inner winding form a single turn winding, and are connected in series to each other.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a power supply device, and more particularly to a power supply device used in a mass spectrometer. [Background technology]

[0002] A mass spectrometer is an instrument that identifies or analyzes chemical substances through mass analysis. Such a mass spectrometer can analyze the constituent components of a sample by measuring the mass of the substance using its mass-to-charge ratio. A variety of methods can be used to ionize a sample within a mass spectrometer. The ionized sample is accelerated as it passes through an electric and / or magnetic field. This means that some or all of the ionized sample has its path bent by the electric and / or magnetic field. A detector can detect the ionized sample.

[0003] In quadrupole mass spectrometry, DC voltage and RF voltage can be applied to the quadrupole. The power supply can amplify the output of the RF power supply through a transformer and apply it to the quadrupole. An air core transformer is used as the transformer that amplifies the output of the RF power supply. In this case, a method is required to reduce the size while maintaining the transformer coefficient corresponding to the transformation ratio. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2018-126049 Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been made in consideration of the problems of the prior art, and the technical object of the present invention is to provide a compact transformer and a power supply device including a compact transformer while maintaining the transformer coefficient.

[0006] The problems to be solved by the present invention are not limited to those mentioned above, and another problem not mentioned will be clearly understood by a person having ordinary skill in the art from the following description. [Means for solving the problem]

[0007] A power supply device according to one embodiment of the present invention includes an RF power supply, a magnetic core transformer including a first transformer unit and a second transformer unit that boosts the output of the RF power supply, a DC decoupling capacitor connected between a first terminal of each of the first and second transformer units and ground, a variable capacitor connected between a second terminal of each of the first and second transformer units and ground, a DC power supply that supplies a DC voltage to the first terminal, and output terminals that output the DC voltage and a boosted RF voltage. Each of the first and second transformer units includes an input coil, a magnetic core, and an output coil. The input coil includes an outer winding and an inner winding, and the outer winding and the inner winding form a single winding and are connected in series.

[0008] According to another embodiment of the present invention, a printed circuit board includes a substrate, a first conductive line disposed on one side of the substrate, and a second conductive line disposed on the other side opposite the first side of the substrate, wherein the first conductive line includes an inner winding and an outer winding, the inner winding and the outer winding forming a single winding, and the outer winding and the inner winding are connected in series.

[0009] A magnetic core transformer according to another embodiment of the present invention includes first and second magnetic cores, and first and second printed circuit boards each having a first conductive line disposed on one side and a second conductive line disposed on the other side opposite the first side, the first conductive line including an inner winding and an outer winding, the inner winding and the outer winding constituting a single winding, and the outer winding and the inner winding are connected in series. [Effects of the Invention]

[0010] The power supply device, magnetic core transformer and printed circuit board according to the embodiments of the present invention can achieve a transformer coefficient that exceeds the winding ratio of the input coil and the output coil through the structure of the input coil. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a circuit diagram showing a power supply device for a mass spectrometer. [Figure 2] FIG. 1 is a circuit diagram illustrating a power supply device for a mass spectrometer according to an embodiment of the present invention. [Figure 3] 3 is a diagram showing a vertical cross section of the magnetic core transformer of FIG. 2. [Figure 4] 4 is a diagram showing a magnetic core and a printed circuit board of the magnetic core transformer of FIG. 3. [Figure 5A] 2 is a plan view of coils of a first conductive line and a second conductive line of a printed circuit board included in a magnetic core transformer according to an embodiment of the present invention. FIG. [Figure 5B] 2 is a plan view of coils of a first conductive line and a second conductive line of a printed circuit board included in a magnetic core transformer according to an embodiment of the present invention. FIG. [Figure 6A] 4 is an exploded view and a combined view of the magnetic core transformer of FIG. 3. [Figure 6B] 4 is an exploded view and a combined view of the magnetic core transformer of FIG. 3. [Figure 7] 4 is a diagram showing the magnetic field formed by the input coil and output coil of the magnetic core transformer of FIG. 3. [Figure 8]3 is an RF equivalent circuit of the power supply device of FIG. 2. [Figure 9A] 9 is a graph showing the characteristics of the RF equivalent circuit of FIG. 8. [Figure 9B] 9 is a graph showing the characteristics of the RF equivalent circuit of FIG. 8. [Figure 9C] 9 is a graph showing the characteristics of the RF equivalent circuit of FIG. 8. DETAILED DESCRIPTION OF THE INVENTION

[0012] In order to fully understand the structure and effects of the present invention, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0013] The present invention is not limited to the embodiments disclosed below, but may be embodied in various forms and may undergo various modifications and changes. However, the description of the present embodiments is provided to ensure complete disclosure of the present invention and to fully convey the scope of the invention to those skilled in the art to which the present invention pertains. In the accompanying drawings, the dimensions of components are shown larger than they actually are for the convenience of explanation, and the proportions of each component may be exaggerated or reduced.

[0014] The terms used in this specification are intended to describe the embodiments and are not intended to limit the present invention. Unless otherwise defined, the terms used in this specification may be interpreted as having the meaning commonly known to those skilled in the art.

[0015] In this disclosure, the singular forms include the plural forms unless the context clearly dictates otherwise. As used herein, "comprises" and / or "comprising" specify the presence of components, steps, operations and / or elements but do not exclude the presence or addition of one or more other components, steps, operations and / or elements.

[0016] In this disclosure, when a layer is referred to as being "on" another layer, it may be formed directly on top of the other layer, or there may be a third layer interposed between them.

[0017] In this disclosure, terms such as "first," "second," etc. are used to describe various regions, layers, etc., but these regions and layers should not be limited by these terms. These terms are merely used to distinguish a given region or layer from other regions or layers. Thus, a portion referred to as a "first portion" in one embodiment may be referred to as a "second portion" in another embodiment. The embodiments described and exemplified herein also include complementary embodiments. Parts designated with the same reference numerals throughout the specification represent the same components.

[0018] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a power supply device according to the present

[0019] 1 is a circuit diagram showing a power supply for a mass spectrometer. Referring to FIG. 1, the power supply 100 for a mass spectrometer includes an RF power supply 110, a transformer 120, a DC power supply 130, output terminals 141 and 142, and a quadrupole mass filter 150.

[0020] The RF power supply 110 generates a high frequency RF voltage that is relatively small in magnitude compared to the output of the power supply 100. The RF voltage generated by the RF power supply 110 may be boosted to a relatively large RF voltage via a transformer 120.

[0021] Transformer 120 includes input coil 121 and output coil 122. An RF voltage generated from an RF power supply is applied to the input coil. The RF voltage applied to the input coil forms a magnetic flux, and an induced electromotive force due to the magnetic flux is applied to output coil 122. Output coil 122 generates a differential RF voltage using a divided inductor.

[0022] The DC power supply 130 adds a DC component to the output voltage through the output coil 122. At this time, the DC voltage component generated via the DC power supply and the RF component transmitted via the output coil 122 are applied to the quadrupole mass filter 150 via output terminals 141 and 142.

[0023] A differential RF voltage and a DC voltage are applied to output terminals 141, 142. The frequency of the RF output via output terminals 141, 142 can reach several megahertz (MHz), and the amplitude of the voltage of the RF output can reach several kilovolts (KV). The voltage of the DC output via output terminals 141, 142 can reach several hundred volts (V). Output terminals 141, 142 deliver the differential RF and DC voltages to quadrupole mass filter 150.

[0024] The quadrupole mass filter 150 comprises four cylindrical rods arranged in parallel. The same power supply is applied to the diagonally arranged rods, and differential RF and DC voltages are applied to adjacent rods. An electromagnetic field is formed in the quadrupole mass filter 150, and ions of various masses are injected between the rods with the same energy. Ions within the quadrupole mass filter 150 can be separated according to mass, allowing the mass of the ions to be analyzed.

[0025] The transformer 120 must satisfy three requirements. First, the output coil 122 of the transformer 120 must provide resonance with other capacitive elements at the operating frequency. Second, the output coil 122 must be able to withstand high voltages. Third, the inductive coupling between the input coil 121 and the output coil 122 must be small enough to match the RF power supply 110, which generates a relatively low voltage. The inductive coupling in the transformer 120 is the electrical interaction caused by the shared magnetic field or magnetic flux between the input coil 121 and the output coil 122. It is expressed as a coupling coefficient between 0 and 1. The transformer coefficient is determined by the number of windings and sensitivity of the input coil 121 and the output coil 122. The higher the transformer coefficient, the more the magnetic field generated in the input coil 121 is transferred to the output coil 122, amplifying the output voltage of the transformer 120. The requirement to sufficiently minimize the inductive coupling between the input coil 121 and the output coil 122 means that the transformer coefficient must be large enough.

[0026] An air core transformer used in the transformer 120 has the advantage of a high Q value, which is a quality factor related to loss due to resistance, but has the disadvantage of being relatively large in size compared to other types of transformers. To reduce the size of the transformer 120 while maintaining the Q value, a magnetic core may be used in the transformer 120. For example, various types of magnetic cores, such as a silicon steel core or a ferrite core, may be used in the transformer 120. A ferrite core is a core made of a material formed by compressing iron powder, and has the advantage of having less eddy current loss in high-frequency power sources compared to a silicon steel core.

[0027] When the magnetic core is applied to the transformer 120, it must also satisfy the three requirements mentioned above. In this case, the output coil 122 must provide resonance with other capacitive elements at the operating frequency, which can be satisfied by determining the air gap of the magnetic core and the winding ratio of the input coil 121 and the output coil 122.

[0028] The fact that the output coil 122 of the magnetic core transformer can withstand high voltages can be met by selecting the creepage distance between adjacent windings of the output coil 122 and adjusting the air gap of the magnetic core.

[0029] The requirement that the inductive coupling between the input coil 121 and the output coil 122 must be small enough to match the RF power supply 110 can be satisfied by increasing the transformer coefficient. In this case, the following two methods can be considered to increase the transformer coefficient.

[0030] First, the turns ratio between the input coil 121 and the output coil 122 can be increased. However, as the number of turns in the output coil 122 increases, the self-inductance of the output coil 122 increases in proportion to the square of the number of turns, which limits resonance with the capacitive element. Note that the number of turns in the input coil 121 cannot be less than 1. Therefore, there is a limit to increasing the turns ratio.

[0031] Second, the coupling coefficient between the input coil 121 and the output coil 122 of the transformer 120 can be reduced. If the transformer 120 is an air-core transformer, the coupling coefficient can be reduced by reducing the area of ​​the input coil 121, dropping the output coil 122 from the input coil, or changing the angle between the geometric axes of the input coil 121 and the output coil 122. However, if a magnetic core is used to reduce the size of the transformer 120, the magnetic flux generated by the input coil 121 is concentrated in the core, which limits the reduction in the coupling coefficient, as with an air-core transformer. Therefore, a new method is needed to reduce the coupling coefficient between the input coil 121 and the output coil 122.

[0032] 2 is a circuit diagram showing a power supply for a mass spectrometer according to an embodiment of the present invention. Referring to FIG. 2, the power supply according to the embodiment of the present invention includes an RF power supply 210, matching capacitors 211 and 212, a magnetic core transformer 220, DC decoupling capacitors 232 and 235, variable capacitors 233 and 236, output terminals 241 and 242, and a quadrupole mass filter 250.

[0033] The RF power supply 210 has a configuration corresponding to that of the RF power supply 110 in Fig. 1 and generates a relatively small RF voltage. The RF voltage generated by the RF power supply 210 is boosted to a relatively large RF voltage via a magnetic core transformer 220.

[0034] The magnetic core transformer 220 includes a first transformer unit 221 and a second transformer unit 224. The first transformer unit 221 includes a portion of the magnetic core MC, a first input coil 222, and a first output coil 223. The second transformer unit 224 includes another portion of the magnetic core MC, a second input coil 225, and a second output coil 226. The RF voltage generated by the RF power source 210 may be input to the first input coil 222 and the second input coil 225, which form a magnetic flux concentrated in the magnetic core MC. The first output coil 223 and the second output coil 226 output a voltage induced by the magnetic flux formed in the magnetic core MC. The first input coil 222 and the second input coil 225 have the same shape, and the first output coil 223 and the second output coil 226 also have the same shape. An air gap G may be formed in the magnetic core MC.

[0035] The first input coil 222 and the second input coil 225 include an inner winding and an outer winding, but the inner winding and the outer winding may be configured as a single winding connected in series. Due to the structure of the first input coil 222 and the second input coil 225, each of the first input coil 222 and the second input coil 225 can add leakage inductance. The leakage inductance acts as a new self-inductance connected in series.

[0036] The matching capacitors 211, 212 are coupled in parallel to the first input coil 222 and the second input coil 225, respectively, to compensate for the leakage inductance added by the structure of the first input coil 222 and the second input coil 225.

[0037] A DC voltage of a first sign (for example, +Vdc) can be applied to the first DC terminal 231, and a DC voltage of a sign different from the first sign (for example, −Vdc) can be applied to the second DC terminal 234.

[0038] The DC decoupling capacitors 232 and 236 connect the RF voltage and the DC voltage, preventing the DC voltage from affecting the RF voltage and improving the accuracy of the analysis.

[0039] Variable capacitors 233 and 236 are coupled between ground and output terminals 241 and 242, respectively. The first output coil 223, the DC decoupling capacitor 232, and the variable capacitor 233 form a first resonant tank (1st RT), and the second output coil 226, the DC decoupling capacitor 235, and the variable capacitor 236 form a second resonant tank (2nd RT). The first resonant tank (1st RT) and the second resonant tank (2nd RT) efficiently transmit the RF output of the operating frequency of the magnetic core transformer 220 to the output terminals 241 and 242. The variable capacitors 233 and 236 are adjusted to resonate at the operating frequency.

[0040] The output terminals 241 and 242 correspond to the output terminals 141 and 142 in Figure 1. A differential RF voltage and a DC voltage are applied to the quadrupole mass filter 250 via the output terminals 241 and 242.

[0041] Quadrupole mass filter 250 corresponds to quadrupole mass filter 150 of FIG.

[0042] Meanwhile, the magnetic core transformer 220 according to the embodiment of the present invention has a relatively small size while meeting the requirements of a transformer through the structure of the first input coil 222 and the second input coil 225.

[0043] Figure 3 is a vertical cross-sectional view of the magnetic core transformer of Figure 2. Referring to Figure 3, the magnetic core transformer 220 of Figure 2 includes a first magnetic core (1st MC), a second magnetic core (2nd MC), a first printed circuit board (1st PCB), and a second printed circuit board.

[0044] The first magnetic core (1st MC) and the second magnetic core (2nd MC) are E-shaped cores. The central protrusions of the first magnetic core (1st MC) and the second magnetic core (2nd MC) pass through holes formed in the centers of the first and second printed circuit boards and are separated by an air gap G. The side protrusions of the first magnetic core (1st MC) and the second magnetic core (2nd MC) are separated by an air gap G on both sides of the first and second printed circuit boards, just like the central protrusions. The air gaps G of the central protrusions and the side protrusions may be equal or different. The air gap G formed between the first magnetic core (1st MC) and the second magnetic core (2nd MC) is determined by comprehensively considering the resonance at the operating frequency and the high voltage applied to the output coil.

[0045] Meanwhile, unlike the symmetrical depiction of the first magnetic core (1st MC) and the second magnetic core (2nd MC) in Figure 3, the first magnetic core (1st MC) and the second magnetic core (2nd MC) may be formed with an asymmetrical structure. For example, the protruding portion of the first magnetic core (1st MC) and the protruding portion of the second magnetic core (2nd MC) may have different lengths. Alternatively, the first magnetic core (1st MC) may be an E-shaped core, while the second magnetic core (2nd MC) may have a shape that does not include a protruding portion.

[0046] The first printed circuit board (1st PCB) and the second printed circuit board (2nd PCB) may be the same printed circuit board.

[0047] The first printed circuit board (1st PCB) includes a substrate BD, a first input coil 222, and a first output coil 223. A hole for inserting a magnetic core may be formed in the center of the substrate BD. The first input coil 222 may be disposed as a conductive line on one side of the first printed circuit board (1st PCB), and the first output coil 223 may be formed as a conductive line on the other side. That is, the conductive lines of the first input coil 222 and the first output coil 223 may be disposed on both sides of the substrate BD in the form of a printed circuit.

[0048] For the second printed circuit board (2nd PCB), similar to the first printed circuit board (1st PCB), the conductive lines of the second input coil 225 and the conductive lines of the second output coil 226 are formed on the substrate BD in the manner of a printed circuit.

[0049] In the assembly of the magnetic core transformer 220, the first printed circuit board (1st PCB) and the second printed circuit board (2nd PCB) are positioned so that the first input coil 222 and the second input coil 225 face outward, respectively. That is, the first output coil 223 of the first printed circuit board (1st PCB) and the second output coil 226 of the second printed circuit board (2nd PCB) are positioned to face each other. By arranging the first output coil 223 and the second output coil 226 close to each other, the coupling between the output coils 223 and 226 is increased.

[0050] An insulating material is applied to the substrate BD to prevent defects, including short circuits between windings, caused by high voltages being induced on the substrate BD. The first printed circuit board (1st PCB) and the second printed circuit board (2nd PCB) may be attached with an insulating adhesive containing insulating plastic to prevent dielectric breakdown due to high voltages.

[0051] The first printed circuit board (1st PCB) corresponds to the first transformer 221 in FIG. 2, and the second printed circuit board (2nd PCB) corresponds to the second transformer 224 in FIG.

[0052] The substrate BD can be made of various types of substrates such as an FR-4 substrate, a CEM substrate, a metal core substrate, a polyimide substrate, a copper core substrate, a ceramic substrate, or a PTFE substrate.

[0053] The conductive lines of the input coils 222, 225 and the output coils 223, 226 are made of copper, gold, silver, aluminum, steel alloy, etc. Alternatively, the input coils 222, 225 and the output coils 223, 226 may be formed on a single multi-layer printed circuit board. The first magnetic core (1st MC) and the second magnetic core (2nd MC) may be ferrite cores.

[0054] Figure 4 is a diagram showing the magnetic core and printed circuit board of the magnetic core transformer of Figure 3. Referring to Figure 3, the printed circuit board PCB includes a substrate BD, a first conductive line (1st CL) and a second conductive line (2nd CL).

[0055] A hole is formed in the center of the substrate BD to allow the magnetic core MC to pass through. The first conductive line (1st CL) has a structure in which an outer winding OT and an inner winding IT are connected in series as a single winding. At this time, currents of the same magnitude but opposite directions flow through the adjacent inner winding IT and outer winding OT. For example, currents I1 and I2 flowing through the first conductive line (1st CL) are equal in magnitude but opposite in direction.

[0056] The second conductive line (2nd CL) is formed on the opposite side of the substrate BD from the side on which the first conductive line (1st CL) is formed. The second conductive line (2nd CL) is a single-layer spiral coil with a specific number of turns. The number of turns of the second conductive line (2nd CL) is determined by comprehensively considering resonance at the operating frequency, creepage distance to prevent dielectric breakdown due to high voltage, and transformer coefficient.

[0057] The magnetic field in the inner region surrounded by the inner winding IT of the first conductive line (1st CL) and the region outside the outer winding OT decreases, resulting in magnetic coupling with the second conductive line (2nd CL). The magnetic field in the region between the inner winding IT and the outer winding OT increases, but the region is not magnetically coupled with the second conductive line (2nd CL). This reduces the coupling between the first conductive line (1st CL) and the second conductive line (2nd CL), and a certain amount of magnetic energy is stored only in the first conductive line (1st CL) rather than being transferred to the second conductive line (2nd CL). In other words, the mutual inductance between the first conductive line (1st CL) and the second conductive line (2nd CL) decreases, and leakage inductance is added to the first conductive line (1st CL). The leakage inductance acts as a new self-inductance connected in series with the first conductive line (1st CL). That is, the coupling coefficient between the first conductive line (1st CL) and the second conductive line (2nd CL) may be reduced, and the transformer coefficient may be increased while minimizing the number of windings of the second conductive line (2nd CL).

[0058] 5A and 5B are plan views of coils of a first conductive line and a second conductive line on a printed circuit board included in a magnetic core transformer according to an embodiment of the present invention. Referring to FIG. 5A and FIG. 5B, the first conductive line (1st CL) includes an outer winding OT and an inner winding IT connected in series to form a single winding.

[0059] A hole H through which the magnetic core passes is formed in the center of the substrate BD.

[0060] The first conductive line (1st CL) is disposed on the first surface SD1 of the substrate BD. The region in which a magnetic field is formed by the first conductive line (1st CL) is divided into a first region A1, a second region A2, and a third region A3 according to the inner winding IT and the outer winding OT. The first region A1 is an internal region of the inner winding IT, the second region A2 is a region between the inner winding IT and the outer winding OT, and the third region A3 is an external region of the outer winding.

[0061] The second conductive line (2nd CL) is disposed on the second surface SD2 of the substrate BD. The second surface SD2 is the opposite surface to the first surface SD1. The second conductive line (2nd CL) is in the shape of a spiral coil around a hole H formed in the center of the substrate.

[0062] As described in FIG. 4, the magnetic fields formed in the first region A1 and the third region A3 of the magnetic field generated by the RF voltage of the first conductive line (1st CL) magnetically couple the first conductive line (1st CL) and the second conductive line (2nd CL). Meanwhile, the magnetic field generated in the second region A2 does not couple with the second conductive line (2nd CL) and forms a leakage inductance. The leakage inductance in the second region may be treated as a self-inductance connected in series to the first conductive line (1st CL).

[0063] The structure of the first conductive line (1st CL) in which the inner winding IT and the outer winding OT are connected in series as a single winding reduces the coupling coefficient between the first conductive line (1st CL) and the second conductive line (2dCL), and increases the transformer coefficient while minimizing the number of windings of the second conductive line (2nd CL).

[0064] The first conductive line (1st CL) corresponds to the first input coil 222 or the second input coil 225 of the magnetic core transformer 220 in FIG. 2, and the second conductive line (2nd CL) corresponds to the first output coil 223 or the second output coil 226 of the magnetic core transformer 220 in FIG. 2.

[0065] 6A and 6B are exploded and assembled views of the magnetic core transformer of FIG. 3. Referring to FIGS. 6A and 6B, the assembly of the magnetic core transformer 220 can be seen. The assembly of the magnetic core transformer 220 is composed of a first magnetic core (1st MC), a second magnetic core (2nd MC), a first printed circuit board (1st PCB), and a second printed circuit board (2nd PCB).

[0066] The first magnetic core (1st MC) and the second magnetic core (2nd MC) are E-shaped magnetic cores with side protrusions and a central protrusion. The central protrusion of the first magnetic core (1st MC) passes through a hole formed in the center of the first printed circuit board (1st PCB), and the side protrusions cover the sides of the first printed circuit board (1st PCB). The first printed circuit board (1st PCB) is assembled with the first magnetic core (1st MC) so that the input coil is located on the first magnetic core (1st MC) side. The second magnetic core (2nd MC) and the second printed circuit board (2nd PCB) are also assembled in the same manner as described above.

[0067] An air gap G is formed between the first magnetic core (1st MC) and the second magnetic core (2nd MC). The air gap G is adjusted so that the RF voltage output by the output coil at the operating frequency resonates with other capacitive elements.

[0068] As described above, the first printed circuit board (1st PCB) and the second printed circuit board (2nd PCB) are attached with an insulating adhesive.

[0069] Figure 7 is a diagram showing the magnetic field formed by the input coil and output coil of the magnetic core transformer of Figure 3. Referring to Figure 7, magnetic coupling between the input coils 222, 225 and the output coils 223, 226 can be seen.

[0070] The first magnetic field MF1 is the magnetic field generated by the input coils 222, 225. Depending on the configuration of the input coils 222, 225 described above, magnetic flux MFX is added in the region between the inner and outer windings of the input coils 222, 225, and magnetic flux MFX is reduced in the interior region of the inner windings and the exterior region of the outer windings.

[0071] The second magnetic field MF2 is a magnetic field formed by the output coils 223 and 226. In the case of the output coils 223 and 226, most of the magnetic flux MFX is concentrated in the magnetic cores (1st MC and 2nd MC). Of the total magnetic flux MFX, only some of the magnetic flux MFX is coupled to both the input coils 222 and 225 and the output coils 223 and 226. This confirms that the coupling coefficient between the input coils 222 and 225 and the output coils 223 and 226 is reduced.

[0072] Figure 8 is an RF equivalent circuit of the power supply device of Figure 2. Referring to Figure 8, the power supply device of Figure 2 is represented by an RF equivalent circuit 300, which includes an input voltage Vin, a first capacitor C1, a first inductor L1, a second inductor L2, a third inductor L3, a fourth inductor L4, a second capacitor C2, a resistor R, and an output voltage Vout. In this case, the DC elements of Figure 2 may be ignored.

[0073] 2. The first inductor L1 corresponds to the first input coil 222, the second inductor L2 corresponds to the second input coil 225, the third inductor L3 corresponds to the first output coil 223, and the fourth inductor L4 corresponds to the second output coil 226. The first capacitor C1 corresponds to the matching capacitors 211 and 212 in FIG. 2. The second capacitor C2 corresponds to the variable capacitors 233 and 236, the capacitance of the quadrupole mass filter 250, and the capacitance of the connecting conductors in FIG. 2. The resistance R corresponds to the resistance of losses generated from the magnetic core MC in FIG. 2.

[0074] The self-inductances L11, L22, L33, and L44 of the inductors L1 to L4 in the RF equivalent circuit 300 are as shown in Table 1.

[0075] [Table 1]

[0076] The mutual inductances L12, L13, L14, L23, L24, and L34 of the inductors L1 to L4 in the RF equivalent circuit 300 are as shown in Table 2 below.

[0077] [Table 2]

[0078] The coupling coefficients K12, K13, K14, K23, K24, and K34 of the inductors L1 to L4 in the RF equivalent circuit 300 are as shown in Table 3 below.

[0079] [Table 3]

[0080] The capacitance of the first capacitor C1 is 1.61E-8 Farat (F), the capacitance of the second capacitor C2 is 5.355E-11 Farat (F), and the magnitude of the resistor R is 2.00E+5 ohms (ohms).

[0081] The RF equivalent circuit 300 can function as a bandpass filter. The bandpass filter of the RF equivalent circuit 300 is composed of a low-impedance resonant tank including a first capacitor C1, a first inductor L1, and a second inductor L2, and a high-impedance resonant tank including a second capacitor C2, a third inductor L3, and a fourth inductor L4. The characteristics of the RF equivalent circuit 300 will be described below with reference to FIGS. 9A to 9C.

[0082] 9A to 9C are graphs showing the characteristics of the RF equivalent circuit of FIG. 8. Referring to FIG. 9A, the effective transformer coefficient of the RF equivalent circuit 300 can be seen. In the RF equivalent circuit 300, the turns ratio between the first inductor L1 and the third inductor L3 is 14. That is, the number of turns of the first inductor L1 is 1, and the number of turns of the third inductor L3 is 14. However, due to the structural characteristics of the first inductor L1 and the second inductor L2, the coupling coefficients K13 and K24 between the first inductor L1 and the third inductor L3 and the second inductor L2 and the fourth inductor L4 are relatively small. In the graph of FIG. 9A, the operating frequency is 1.50 megahertz (MHz), and the ratio of the input voltage Vin to the output voltage Vout at the operating frequency is 76. For a conventional magnetic core transformer, the transformer coefficient must be the turns ratio of 14 or a similar value. Meanwhile, it can be seen that the coupling coefficients K13 and K24 are reduced and the effective transformer coefficient reaches 76 due to the input coil structure according to the embodiment of the present invention.

[0083] 9B and 9C show the magnitude and phase of the input impedance, respectively. At 1.5 megahertz (MHz), which is the operating frequency of the RF equivalent circuit 300, the phase of the input impedance becomes zero and the magnitude of the input impedance has a minimum value. At this time, it can be confirmed that the RF equivalent circuit 300 functions as a bandpass filter.

[0084] Although the embodiments of the present invention have been described above with reference to the accompanying drawings, those skilled in the art will understand that the present invention may be embodied in other specific forms without changing the technical spirit or essential characteristics of the present invention. Therefore, it should be understood that the embodiments described above are examples in all respects and are not limiting. [Explanation of symbols]

[0085] 100 Power supply 110 RF power supply 120 Transformer 130 DC power supply 141, 142 output terminals 150 Quadrupole Mass Filter 210 RF power supply 220 Magnetic Core Transformer 221 Transformer No. 1 222 First input coil 223 First output coil 224 Second Transformer Section 225 Second input coil 226 Second output coil 231 1st DC power supply terminal 232, 235 DC decoupling capacitor 233, 236 variable capacitor 234 2nd DC power supply terminal 241, 242 output terminals 250 Quadrupole Mass Filter

Claims

1. an RF power source; a magnetic core transformer including a first transformer unit and a second transformer unit that boosts the output of the RF power supply; a DC decoupling capacitor connected between a first terminal of each of the first and second transformer output terminals and ground; a variable capacitor connected between a second terminal of each of the first and second transformer units and ground; a DC power supply that supplies a DC voltage to the first terminal; an output terminal for outputting the DC voltage and the boosted RF voltage, each of the first transformer unit and the second transformer unit includes an input coil, a magnetic core, and an output coil; the input coil includes an outer winding and an inner winding, the outer winding and the inner winding form a single winding, and the outer winding and the inner winding are connected in series; each of the first transformer unit and the second transformer unit further includes a substrate; the input coil is formed on a first surface of the substrate, and the output coil is formed on a second surface of the substrate opposite to the first surface, The power supply device according to claim 1, wherein the output coil of the first transformer unit and the output coil of the second transformer unit are attached to the respective substrates so as to face each other.

2. 2. The power supply device according to claim 1, wherein the magnetic core of the first transformer unit and the magnetic core of the second transformer unit form an air gap.

3. The power supply device according to claim 1 , further comprising: a matching capacitor connected in parallel to both ends of the input coils of the first transformer and the second transformer.

4. 4. The power supply device according to claim 3, wherein the magnitude of each of the matching capacitors is determined so as to match the leakage impedance of each of the input coils of the first transformer unit and the second transformer unit.

5. 2. The power supply device according to claim 1, wherein the size of each of the DC decoupling capacitors is adjusted so as to resonate with each of the output coils of the first transformer unit and the second transformer unit and each of the variable capacitors.

6. 2. The power supply device according to claim 1, wherein the cores of the first transformer section and the second transformer section are E-shaped ferrite cores.

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