JP4900623B2 - Compound balun - Google Patents

Description

  The present invention relates to a composite balun that combines a balanced transmission line and an unbalanced transmission line.

  Conventionally, a chip-shaped laminated balun is known as a balanced-unbalanced converter of a transmission line in a high-frequency circuit. The balun usually includes a first and second line portions that constitute a pair of balanced transmission lines, a third and fourth line portions that constitute one unbalanced transmission line that is electromagnetically coupled to the balanced transmission lines, and a ground electrode. And a laminated body formed by stacking a plurality of dielectric sheets. The first line portion and the third line portion are electromagnetically coupled to each other at a portion facing each other across the dielectric sheet to form a coupler. Similarly, the second line portion and the fourth line portion sandwich the dielectric sheet. The coupler is configured by electromagnetic coupling at the opposing portions.

  However, since the conventional stacked balun had only one balun built in one chip, for example, when it is necessary to incorporate a plurality of baluns into a mobile communication device such as a mobile phone, a wireless LAN, etc. It was necessary to secure a plurality of mounting areas on the printed circuit board. Therefore, there has been a problem that the communication apparatus is increased in size.

  Attempts have already been made to solve the above-mentioned problems. For example, Patent Document 1 includes a plurality of baluns, each of which is a pair of balanced transmission lines, one unbalanced transmission line electromagnetically coupled to the pair of balanced transmission lines via a dielectric layer, and balanced transmission. Disclosed is a multilayer composite balun configured by stacking a ground electrode and a plurality of dielectric layers that are opposed to each other via a dielectric layer on at least one of a transmission line and an unbalanced transmission line. .

  By the way, when the composite balun is inserted in the front stage of the power amplifier PA of the mobile communication device and the differential input to the power amplifier is supplied from the balun in advance, the composite balun is arranged in the subsequent stage of the radio frequency integrated circuit RFIC, and the balun is When the power is supplied to the radio frequency integrated circuit RFIC via the DC voltage, it is necessary to supply a DC voltage to the power amplifier PA and the radio frequency integrated circuit RFIC through the composite balun. Patent Document 1 does not disclose a configuration for satisfying such a requirement. Further, if a DC voltage is supplied to the power amplifier PA and the radio frequency integrated circuit RFIC through the composite balun, a countermeasure against noise entering through the power supply circuit is necessary. Patent Document 1 does not disclose anything.

JP 2002-329611 A

  An object of the present invention is to provide a composite balun that is useful when a DC voltage needs to be supplied to a power amplifier or a radio frequency integrated circuit.

  Another object of the present invention is to provide a composite balun that takes measures against noise that enters through a power supply circuit when a DC voltage needs to be supplied to a power amplifier or a radio frequency integrated circuit. It is.

  In order to solve the above-described problem, a composite balun according to the present invention includes a plurality of baluns, at least one capacitor, and a DC voltage supply terminal. The plurality of baluns and the capacitor are built in one chip. Each of the baluns includes first to fourth coupled lines, a first balanced terminal, a second balanced terminal, and an unbalanced terminal. One end of the first coupled line is connected to the unbalanced terminal, and one end of the second coupled line is connected to the other end of the first coupled line. The third coupled line is electromagnetically coupled to the first coupled line, one end is connected to the first balanced terminal, the other end is connected to the DC voltage supply terminal, and the fourth coupled line is The second coupling line is electromagnetically coupled, one end is connected to the second balanced terminal, and the other end is connected to the DC voltage supply terminal. One end of the capacitor is connected to the DC voltage supply terminal, and the other end is led to a ground terminal.

  As described above, in the composite balun according to the present invention, a plurality of baluns, which are the main parts, are built in one chip. In the case of incorporating into a circuit board, etc., it is sufficient to secure a mounting area for one or more pieces on a printed circuit board, and it is possible to meet the demand for downsizing.

  In each of the plurality of baluns, one end of the first coupled line is connected to the unbalanced terminal, one end of the second coupled line is connected to the other end of the first coupled line, and the third coupled line is Since the first coupling line is electromagnetically coupled, one end is connected to the first balanced terminal, the fourth coupled line is electromagnetically coupled to the second coupled line, and one end is connected to the second balanced terminal, the third In addition, a composite balun is obtained in which the fourth coupled line is a balanced transmission line and the first and second coupled lines are unbalanced transmission lines.

  Since the other end of the third coupled line is connected to the DC voltage supply terminal and the other end of the fourth coupled line is connected to the DC voltage supply terminal, the DC voltage is applied to the power amplifier or the radio frequency integrated circuit. When it is necessary to supply, a user-friendly composite balun that can supply a DC voltage through the composite balun is obtained.

  Further, since the capacitor includes a capacitor having one end connected to the DC voltage supply terminal and the other end guided to the ground terminal, noise entering through the power supply circuit can be absorbed by the capacitor. In addition, since this capacitor is built in one chip together with a plurality of baluns, the mounting work on the user side becomes easier and the circuit board can be used as compared with the case where the capacitors are externally attached to the composite balun. The mounting area seen above is reduced.

As described above, according to the present invention, the following effects can be obtained.
(A) It is possible to provide a composite balun that is useful when a DC voltage needs to be supplied to a power amplifier or a radio frequency integrated circuit.
(B) When it is necessary to supply a DC voltage to a power amplifier or a radio frequency integrated circuit, it is possible to provide a composite balun that can prevent noise entering through the power supply circuit.

  Other objects, configurations and advantages of the present invention will be described in more detail with reference to the accompanying drawings. The accompanying drawings are merely examples.

It is a circuit diagram which shows the structure of the composite balun which concerns on this invention. It is a circuit diagram which shows another example of the composite balun which concerns on this invention. It is a circuit diagram which shows the use condition of the composite balun shown in FIG. It is an exploded view which shows the laminated structure of the composite balun which concerns on this invention. It is a figure which shows the terminal arrangement | positioning which looked at the chip | tip which comprises the composite balun which concerns on this invention from the bottom face side. It is a perspective view which shows the laminated structure of a capacitor among the laminated structures shown in FIG. It is a perspective view which shows the laminated structure of the balun main part among the laminated structures shown in FIG.

  Referring to FIG. 1, the composite balun according to the present invention includes a plurality of baluns BL1 to BL3, at least one capacitor C11 to C13, and a DC voltage supply terminal T20. Although the number of baluns BL1 to BL3 is three in the drawing, two or more baluns are sufficient. The capacitors C11 to C13 basically correspond to the number of baluns BL1 to BL3.

  The baluns BL1 to BL3 and the capacitors C11 to C13 are built in one chip 1. Such a chip 1 is usually composed of a hexahedral ceramic dielectric, and a necessary conductor pattern is buried in a layer inside thereof, and the conductor pattern is made conductive by a through electrode disposed between the layers. can get.

  Each of the baluns BL1 to BL3 includes first to fourth coupled lines (L11 to L14) to (L31 to L34), a first balanced terminal (T2, T5, T8), and a second balanced terminal (T1, T6, T9) and unbalanced terminals (T15, T18, T12).

  The basic configurations of the baluns BL1 to BL3 are the same. However, since the resonance frequencies are different from each other, the pattern and length of the coupled line are different. The baluns BL1 to BL3 are individually described as follows. First, in the balun BL1, one end of the first coupling line L11 is connected to the unbalanced terminal T18, and one end of the second coupling line L12 is connected to the other end of the first coupling line L11. The third coupled line L13 is electromagnetically coupled to the first coupled line L11, one end is connected to the first balanced terminal T2, the other end is connected to the DC voltage supply terminal T20, and the fourth coupled line L14 is The two coupled lines L12 are electromagnetically coupled, one end is connected to the second balanced terminal T1, and the other end is connected to the DC voltage supply terminal T20. The first to fourth coupled lines L11 to L14 are configured as strip lines having a line length of λ / 4 with respect to the wavelength λ of the target frequency signal. The first coupling line L11 and the third coupling line L13 are opposed to each other with the ceramic dielectric layer in between, thereby causing electromagnetic coupling. The second coupling line L12 and the fourth coupling line L14 are the same, and are opposed to each other with the ceramic dielectric layer interposed therebetween, thereby causing electromagnetic coupling.

  One end of the capacitor C11 is connected to the DC voltage supply terminal T20, and the other end is led to the ground terminal. The capacitor C11 includes at least a pair of electrodes facing each other with the ceramic dielectric layer constituting the chip interposed therebetween, and is determined by the dielectric constant, thickness, and electrode area of the ceramic dielectric layer.

  Next, in the balun BL2, one end of the first coupling line L21 is connected to the unbalanced terminal T15, and one end of the second coupling line L22 is connected to the other end of the first coupling line L21. The third coupled line L23 is electromagnetically coupled to the first coupled line L21, one end is connected to the first balanced terminal T5, and the other end is connected to the DC voltage supply terminal T20. The fourth coupled line L24 is electromagnetically coupled to the second coupled line L22, one end is connected to the second balanced terminal T6, and the other end is connected to the DC voltage supply terminal T20. The first to fourth coupled lines L21 to L24 are also configured as strip lines having a line length of λ / 4 with respect to the wavelength λ of the target frequency signal. The first coupling line L21 and the third coupling line L23 are opposed to each other with the dielectric layer interposed therebetween, thereby causing electromagnetic coupling. The same applies to the second coupling line L22 and the fourth coupling line L24, which face each other with the dielectric layer in between, thereby causing electromagnetic coupling.

  One end of the capacitor C12 is connected to the DC voltage supply terminal T20, and the other end is led to the ground terminal. The capacitor C12 includes at least a pair of electrodes facing each other with the ceramic dielectric layer constituting the chip interposed therebetween, and is determined by the dielectric constant, thickness, and electrode area of the ceramic dielectric layer.

  Further, in the balun BL3, one end of the first coupling line L31 is connected to the unbalanced terminal T12, and one end of the second coupling line L32 is connected to the other end of the first coupling line L31. The third coupled line L33 is electromagnetically coupled to the first coupled line L31, one end is connected to the first balanced terminal T8, the other end is connected to the DC voltage supply terminal T20, and the fourth coupled line L34 is The two coupled lines L32 are electromagnetically coupled, one end is connected to the second balanced terminal T9, and the other end is connected to the DC voltage supply terminal T20. The first to fourth coupled lines L31 to L34 are configured as strip lines having a line length of λ / 4 with respect to the wavelength λ of the target frequency signal. The first coupling line L31 and the third coupling line L33 are opposed to each other with the ceramic dielectric layer interposed therebetween, thereby causing electromagnetic coupling. The second coupling line L32 and the fourth coupling line L34 are the same, and are opposed to each other with the ceramic dielectric layer interposed therebetween, thereby generating electromagnetic coupling.

  One end of the capacitor C13 is connected to the DC voltage supply terminal T20, and the other end is led to the ground terminal. The capacitor C13 includes at least a pair of electrodes facing each other across the ceramic dielectric layer constituting the chip, and is determined by the dielectric constant, thickness, and electrode area of the ceramic dielectric layer.

  As described above, in the composite balun according to the present invention, the plurality of baluns BL1 to BL3, which are the main parts, are built in one chip 1. Therefore, the plurality of baluns BL1 to BL3 are connected to a mobile phone or the like. When incorporated into a mobile communication device, wireless LAN, or the like, a mounting area for one piece may be secured on the printed circuit board, and a demand for miniaturization can be met.

  In each of the plurality of baluns BL1 to BL3, one end of the first coupled line (L11, L21, L31) is connected to the unbalanced terminal (T18, T15, T12), and the second coupled line (L12, L22, L32) has one end connected to the other end of the first coupled line (L11, L21, L31), and the third coupled line (L13, L23, L33) is the first coupled line (L11, L21, L31). Are coupled to the first balanced terminals (T2, T5, T8), and the fourth coupled lines (L14, L24, L34) are electromagnetically coupled to the second coupled lines (L12, L22, L32). Since one end is connected to the second balanced terminal (T1, T6, T9), the third and fourth coupled lines (L13, L23, L33), (L14, L24, L34) are used as balanced transmission lines. 1 and 2 If line (L11, L21, L31), the composite balun is obtained and (L12, L22, L32) the unbalanced transmission line.

  The other end of the third coupled line (L13, L23, L33) is connected to the DC voltage supply terminal T20, and the other end of the fourth coupled line (L14, L24, L34) is connected to the DC voltage supply terminal T20. Therefore, when it is necessary to supply a DC voltage to a power amplifier or a radio frequency integrated circuit, an easy-to-use composite balun that can supply a DC voltage through the composite balun can be obtained.

  Furthermore, since it includes capacitors C11 to C13 having one end connected to the DC voltage supply terminal T20 and the other end led to the ground terminal, noise entering through the power supply circuit is absorbed by the capacitors C11 to C13. Can do. In addition, since the capacitors C11 to C13 are built in one chip 1 together with a plurality of baluns BL1 to BL3, the user-side capacitors C11 to C13 are compared with the case where the capacitors C11 to C13 are externally attached to the composite balun. The mounting work is facilitated and the mounting area viewed on the circuit board is reduced.

  Next, another embodiment of the composite balun according to the present invention will be described with reference to FIG. In FIG. 2, the same reference numerals are given to the components that are the same as the components that appear in FIG. 1, and duplicate descriptions are omitted. A feature of this embodiment is that the capacitor C1 is shared by the plurality of baluns BL1 to BL3. That is, the baluns BL1 to BL3 are plural, but the capacitor C1 is only one on the circuit. Even when a plurality of capacitors are connected in parallel or in series, if they are equivalently expressed as one capacitor on the electric circuit, this is one capacitor.

  If it is the said structure, since the capacitor C1 may be sufficient while providing several baluns BL1-BL3, size reduction can be advanced further. In addition, it is possible to simplify the laminated structure in the case of actual production, contributing to downsizing and cost reduction.

  Next, an example in which the composite balun shown in FIG. 2 is used will be described with reference to FIG. The composite balun shown in FIG. 1 can be used in the same state. The power amplifiers PA1 to PA3 are connected to the unbalanced terminals T18, T15, and T12 of the baluns BL1 to BL3, respectively, and a pair of balanced terminals (T2, T1), (T5, T6), and (T8, T9). Each of these is connected to radio frequency integrated circuits RFIC1 to RFIC4. Each of the baluns BL1 to BL3 is interposed between the radio frequency integrated circuits RFIC1 to RFIC4 that handle balanced signals and the power amplifiers PA1 to PA3 that handle unbalanced signals, and operate as a balanced-unbalanced converter.

  In this case, as already described, in the composite balun according to the present invention, the other end of the third coupled line (L13, L23, L33) is connected to the DC voltage supply terminal T20, and the fourth coupled line (L14 , L24, and L34) are connected to the DC voltage supply terminal T20 at the other end, so that the power amplifiers PA1 to PA3 and the radio frequency integrated circuits RFIC1 to RFIC4 that need to supply a DC voltage are DC-connected through a composite balun. The voltage Vcc can be supplied.

  Furthermore, since the capacitor C1 having one end connected to the DC voltage supply terminal T20 and the other end led to the ground terminal GROUND is included, noise entering through the power supply circuit can be absorbed by the capacitor C1. In addition, since the capacitor C1 is built in one chip 1 together with a plurality of baluns BL1 to BL3, the mounting work on the user side is easy as compared with the case where the capacitor C1 is externally attached to the composite balun. At the same time, the mounting area viewed on the circuit board is reduced.

  Next, a specific laminated structure of the composite balun illustrated in FIG. 2 will be described with reference to FIGS. First, referring to FIG. 4, a structure in which dielectric layers LY1 to LY18 are sequentially stacked is described. The dielectric layers LY1 to LY18 are integrated by firing after laminating ceramic dielectric sheets, and are not actually in the disassembled state shown in the figure. FIG. 4 is an exploded view of each layer simply to explain the structure.

  First, as shown in FIG. 4 in an enlarged manner, the lowermost dielectric layer LY1 has terminals T1 to T20 arranged at predetermined intervals on the periphery of the lower surface. Since the terminals T1 to T20 are formed only on the lower surface of the dielectric layer LY1, when the composite balun is mounted on the substrate, a connection solder fillet is not formed. For this reason, the mounting area is reduced. Among the terminals T1 to T20, the terminal T1 is the second balanced terminal of the balun BL1, the terminal T2 is also the first balanced terminal, the terminals T5 and T6 are the first and second balanced terminals of the balun BL2, and the terminals T8 and T9 are the balun BL3. The first and second balanced terminals are respectively configured. The terminal T18 is an unbalanced terminal of the balun BL1, the terminal 15 is an unbalanced terminal of the balun BL2, and the terminal 12 is an unbalanced terminal of the balun BL3. The remaining terminals T3, T4, T7, T10, T11, T13, T14, T16, T17 and T19 are used as ground terminals. Terminal T20 is a DC voltage supply terminal.

  Next, the dielectric layers LY2, LY3, and LY4 that sequentially overlap the dielectric layer LY1 constitute the capacitor C1 shown in FIG. As shown in FIG. 6 in an enlarged manner, the capacitor C1 includes an electrode E1 formed on the surface of the intermediate dielectric layer LY3 and a ground electrode G1 formed on the surface of the dielectric layer LY2 positioned therebelow. And a capacitor C02 generated between the electrode E1 of the dielectric layer LY3 and the ground electrode G2 formed on the surface of the dielectric layer LY4 positioned thereon are connected in parallel. . Accordingly, the capacitance C1 of the capacitor C1 is C1 = C01 + C02.

  The dielectric layer LY5 located on the dielectric layer LY4 is a spacer layer provided with a group of through electrodes H, and a dielectric layer LY6 having a wiring pattern group P1 and a dielectric layer having a wiring pattern group P2 thereon. The body layers LY7 are sequentially overlapped.

  The dielectric layers LY8 to LY15 sequentially overlapping the dielectric layer LY7 are used to configure the first to fourth coupled lines of the baluns BL1 to BL3. The details are shown in FIG. Referring to FIG. 7, first, on one surface of the dielectric layer LY8, a strip-shaped conductor constituting the fourth coupled line L14 of the balun BL1 and a strip-shaped conductor constituting the third coupled line L13 are spaced apart. They are arranged side by side in one direction. In the lateral direction of the third coupled line L13, the strip-shaped conductors constituting the third coupled line L23 of the balun BL2 and the strip-shaped conductors also constituting the fourth coupled line L24 are spaced apart from each other at an interval. They are arranged side by side in one direction. Further, in the lateral direction of the fourth coupling line L24 of the balun BL2, the strip-shaped conductors constituting the third coupling line L33 of the balun BL3 and the strip-like conductors constituting the fourth coupling line L34 are spaced apart from each other. They are arranged side by side in one direction at intervals.

  Next, on one surface of the dielectric layer LY9 overlying the dielectric layer LY8, a strip-like conductor constituting the second coupling line L12 of the balun BL1 and a strip-like conductor similarly constituting the first coupling line L11 are provided. They are arranged side by side in one direction at intervals. In the lateral direction of the first coupling line L11, the strip-like conductors constituting the first coupling line L21 of the balun BL2 and the strip-like conductors constituting the second coupling line L22 are spaced apart from each other with a gap therebetween. They are arranged side by side in one direction. Further, in the lateral direction of the second coupling line L22 of the balun BL2, a strip-shaped conductor constituting the first coupling line L31 of the balun BL3 and a strip-like conductor also constituting the second coupling line L32 are spaced apart from each other. They are arranged side by side in one direction at intervals.

  Therefore, between the dielectric layer LY8 and the dielectric layer LY9, with respect to the balun BL1, the first coupled line L11 and the third coupled line L13, and the second coupled line L12 and the fourth coupled line L14 are dielectric layers. Electromagnetic coupling is performed via LY9. Regarding the balun BL2, the first coupled line L21 and the third coupled line L23, and the second coupled line L22 and the fourth coupled line L24 are electromagnetically coupled through the dielectric layer LY9. Further, regarding the balun BL3, the first coupling line L31 and the third coupling line L33, and the second coupling line L32 and the fourth coupling line L34 are electromagnetically coupled via the dielectric layer LY9.

  Next, on one surface of the dielectric layer LY10 overlying the dielectric layer LY9, a strip-like conductor constituting the fourth coupling line L14 of the balun BL1, and a strip-like conductor also constituting the third coupling line L13 are provided. Are arranged side by side in one direction at intervals. In the lateral direction of the third coupled line L13, the strip-shaped conductors constituting the third coupled line L23 of the balun BL2 and the strip-shaped conductors also constituting the fourth coupled line L24 are spaced apart from each other at an interval. They are arranged side by side in one direction. Further, in the lateral direction of the fourth coupling line L24 of the balun BL2, a strip-like conductor constituting the third coupling line L33 of the balun BL3 and a strip-like conductor also constituting the fourth coupling line L34 are spaced apart from each other. Are arranged side by side in one direction at intervals.

  Therefore, between the dielectric layer LY9 and the dielectric layer LY10, with respect to the balun BL1, the first coupling line L11 and the third coupling line L13, and the second coupling line L12 and the fourth coupling line L14 are dielectrics. Electromagnetic coupling will occur through the layer LY10. Regarding the balun BL2, the first coupling line L21 and the third coupling line L23, and the second coupling line L22 and the fourth coupling line L24 are electromagnetically coupled via the dielectric layer LY10. Further, regarding the balun BL3, the first coupling line L31 and the third coupling line L33, and the second coupling line L32 and the fourth coupling line L34 are electromagnetically coupled through the dielectric layer LY10.

  Next, on one surface of the dielectric layer LY11 that overlaps the dielectric layer LY10, a strip-shaped conductor that constitutes the second coupling line L12 of the balun BL1, and a strip-like conductor that also constitutes the first coupling line L11. Are arranged side by side in one direction at intervals. In the lateral direction of the first coupled line L11, the strip-shaped conductors constituting the first coupled line L21 of the balun BL2 and the strip-shaped conductors also constituting the second coupled line L22 are spaced apart from each other at an interval. They are arranged side by side in one direction. Further, in the lateral direction of the second coupling line L22 of the balun BL2, a strip-shaped conductor constituting the first coupling line L31 of the balun BL3 and a strip-like conductor also constituting the second coupling line L32 are spaced apart from each other. They are arranged side by side in one direction at intervals.

  Therefore, between the dielectric layer LY10 and the dielectric layer LY11, with respect to the balun BL1, the first coupling line L11 and the third coupling line L13, and the second coupling line L12 and the fourth coupling line L14 are dielectrics. Electromagnetic coupling will occur via the layer LY11. Regarding the balun BL2, the first coupling line L21 and the third coupling line L23, and the second coupling line L22 and the fourth coupling line L24 are electromagnetically coupled via the dielectric layer LY11. Further, regarding the balun BL3, the first coupling line L31 and the third coupling line L33, and the second coupling line L32 and the fourth coupling line L34 are electromagnetically coupled via the dielectric layer LY11.

  Further, on one surface of the dielectric layer LY12 overlapping the dielectric layer LY11, a strip-shaped conductor constituting the fourth coupled line L14 of the balun BL1 and a strip-shaped conductor also constituting the third coupled line L13 are provided. Are arranged side by side in one direction at intervals. In the lateral direction of the third coupled line L13, the strip-shaped conductors constituting the third coupled line L23 of the balun BL2 and the strip-shaped conductors also constituting the fourth coupled line L24 are spaced apart from each other at an interval. They are arranged side by side in one direction. Further, in the lateral direction of the fourth coupling line L24 of the balun BL2, a strip-like conductor constituting the third coupling line L33 of the balun BL3 and a strip-like conductor also constituting the fourth coupling line L34 are spaced apart from each other. Are arranged side by side in one direction at intervals.

  Therefore, between the dielectric layer LY11 and the dielectric layer LY12, with respect to the balun BL1, the first coupling line L11 and the third coupling line L13, and the second coupling line L12 and the fourth coupling line L14 are dielectrics. Electromagnetic coupling will occur through the layer LY12. Regarding the balun BL2, the first coupled line L21 and the third coupled line L23, and the second coupled line L22 and the fourth coupled line L24 are electromagnetically coupled via the dielectric layer LY12. Further, regarding the balun BL3, the first coupling line L31 and the third coupling line L33, and the second coupling line L32 and the fourth coupling line L34 are electromagnetically coupled via the dielectric layer LY12.

  On one surface of the dielectric layer LY13 that overlaps with the dielectric layer LY12, a strip-shaped conductor that constitutes the second coupling line L12 of the balun BL1 and a strip-shaped conductor that also constitutes the first coupling line L11 are spaced apart. They are arranged side by side in one direction with a gap therebetween. In the lateral direction of the first coupled line L11, the strip-shaped conductors constituting the first coupled line L21 of the balun BL2 and the strip-shaped conductors also constituting the second coupled line L22 are spaced apart from each other at an interval. They are arranged side by side in one direction. Further, in the lateral direction of the second coupling line L22 of the balun BL2, a strip-shaped conductor constituting the first coupling line L31 of the balun BL3 and a strip-like conductor also constituting the second coupling line L32 are spaced apart from each other. They are arranged side by side in one direction at intervals.

  Accordingly, between the dielectric layer LY12 and the dielectric layer LY13, with respect to the balun BL1, the first coupling line L11 and the third coupling line L13, and the second coupling line L12 and the fourth coupling line L14 are dielectrics. Electromagnetic coupling will occur through the layer LY13. Regarding the balun BL2, the first coupling line L21 and the third coupling line L23, and the second coupling line L22 and the fourth coupling line L24 are electromagnetically coupled via the dielectric layer LY13. Further, regarding the balun BL3, the first coupling line L31 and the third coupling line L33, and the second coupling line L32 and the fourth coupling line L34 are electromagnetically coupled via the dielectric layer LY13.

  On one surface of the dielectric layer LY14 overlying the dielectric layer LY13, a strip-like conductor constituting the third coupling line L33 of the balun BL3 and a strip-like conductor also constituting the fourth coupling line L34 are mutually connected. They are arranged side by side in one direction at intervals.

  Therefore, between the dielectric layer LY13 and the dielectric layer LY14, the first coupling line L31 and the third coupling line L33, and the second coupling line L32 and the fourth coupling line L34 are related to the balun BL3. Electromagnetic coupling is performed via LY14.

  On one surface of the dielectric layer LY15 overlying the dielectric layer LY14, a strip-like conductor constituting the first coupling line L31 of the balun BL3 and a strip-like conductor constituting the second coupling line L32 are spaced from each other. They are arranged side by side in one direction.

  Therefore, between the dielectric layer LY14 and the dielectric layer LY15, the first coupling line L31 and the third coupling line L33, and the second coupling line L32 and the fourth coupling line L34 are related to the balun BL3. Electromagnetic coupling is performed via LY15.

  As described above, the first coupling line (L11, L21, L31) and the third coupling line (L13, L23, L33) are electromagnetically coupled, and the second coupled line (L12, L22, L32) is coupled to the fourth coupling. Since the electromagnetic coupling of the lines (L14, L24, L34) is multi-layered, a high and stable coupling degree can be obtained. In addition, the required line length can be ensured while reducing the coupled line length per dielectric layer, reducing the plane area, and reducing the size.

  The same coupled line formed in the dielectric layers LY8 to LY15 is connected by the through electrode H so as to have the circuit configuration described in FIG. For example, the fourth coupled line L14 formed on the dielectric layer LY8, the fourth coupled line L14 formed on the dielectric layer LY10, and the fourth coupled line L14 formed on the dielectric layer LY12 are formed of the through electrode H. Are basically connected in series. The first coupled line (L11, L21, L31), the second coupled line (L12, L22, L32), the third coupled line (L13, L23, L33), and the fourth coupled line (L24, L34), A similar connection process using the through electrode H is performed.

  With further reference to FIG. 4, the layers of the ground electrodes G1 and G2 of the capacitor C1 are provided on the lower side (in the drawing) of the dielectric layers LY8 to LY15 constituting the baluns BL1 to BL3. Has a dielectric layer LY17 having a ground electrode G3. That is, a shield structure in which the baluns BL1 to BL3 are sandwiched by the ground electrodes G1, G2, and G3 is obtained. For this reason, a stable shielding effect is obtained.

  The through electrode H mainly includes a first coupled line (L11, L21, L31), a second coupled line (L12, L22, L32), a third coupled line (L13, L23, L33), and a fourth coupled line. (L14, L24, L34) are connected so as to have a predetermined circuit configuration, and the upper and lower ground electrodes G1, G2, and G3 are electrically connected, but the balun BL1 and the balun BL2 By forming a group of through electrodes H connected to the ground electrodes G1, G2 or G3 at a relatively short interval between the baluns BL2 and BL3, mutual interference between the baluns can be blocked. it can.

  Although the contents of the present invention have been specifically described above with reference to the preferred embodiments, it is obvious that those skilled in the art can take various modifications based on the basic technical idea and teachings of the present invention. It is.

BL1, BL2, BL3 Baluns L11, L21, L31 First coupled lines L12, L22, L32 Second coupled lines L13, L23, L33 Third coupled lines L14, L24, L34 Fourth coupled lines C1, C11, C12, C13 Capacitors

Claims (2)

A composite balun including a plurality of baluns, at least one capacitor, and a DC voltage supply terminal,
The plurality of baluns and the capacitor are built in one chip,
Each of the baluns includes first to fourth coupled lines, a first balanced terminal, a second balanced terminal, and an unbalanced terminal,
The first coupling line has one end connected to the unbalanced terminal,
One end of the second coupled line is connected to the other end of the first coupled line,
The third coupled line is electromagnetically coupled to the first coupled line, one end is connected to the first balanced terminal, and the other end is connected to the DC voltage supply terminal,
The fourth coupled line is electromagnetically coupled to the second coupled line, one end is connected to the second balanced terminal, and the other end is connected to the DC voltage supply terminal,
The capacitor has one end connected to the DC voltage supply terminal and the other end led to a ground terminal,
In each of the baluns, the first coupling line and the second coupling line, the third coupling line and the fourth coupling line are electromagnetically coupled via a dielectric layer constituting the chip,
Among the plurality of baluns,
Strip-like conductors constituting the first coupling line and the second coupling line are arranged side by side in one direction at intervals from each other,
The strip-like conductors constituting the third coupled line and the fourth coupled line are arranged side by side in one direction at intervals from each other,
The first balanced terminal, the second balanced terminal, and the unbalanced terminal are arranged at intervals in the periphery of the lower surface of the lowermost dielectric layer,
The unbalanced terminal is disposed on one side of the lowermost dielectric layer,
The first balanced terminal and the second balanced terminal are arranged on the other side facing the one side of the lowermost dielectric layer,
Balun.   2. The composite balun according to claim 1, wherein the capacitor is shared among the plurality of baluns.

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