JP6510350B2 - Directional coupler and high frequency module - Google Patents

Description

  The present invention is directed to a directional coupler including a stacked body in which a plurality of insulating layers are stacked, and a first line and a second line provided on the insulating layer so as to face each other across the insulating layer. And a high frequency module including the directional coupler.

  In recent years, mobile phones have increasingly adopted so-called multi-band systems in which two or more transmission / reception systems are mounted. Although it is necessary to mount a circuit necessary for the configuration of each transmission / reception system in a multiband mobile phone, the circuit becomes complicated. In addition, if the circuit is configured using individual dedicated parts, the size of the device (such as a mobile phone) and the cost increase are caused. Therefore, high frequency modularization which integrated each circuit components, such as a filter element of a transmission-and-reception system, is also advanced. A directional coupler is used as a substrate or a single component for electrically connecting a plurality of circuit components in this high frequency module.

  The directional coupler has a main line through which a high frequency signal is transmitted, and a sub-line electromagnetically coupled to the main line. The main line and the sub line are provided in a stacked body in which a plurality of insulating layers are stacked. The main line and the sub line are electromagnetically coupled to each other by facing each other in the vertical direction with the insulating layer interposed therebetween. The sub-line transmits, for example, a signal for sending back (feedback) electrical information to an element to which the main line is connected. The ratio of the power output from the secondary line to the power input to the main line corresponds to the degree of coupling of the directional coupler.

JP 2000-134008 A

  The adjustment of the degree of coupling in the above directional coupler is performed by the strength of the electromagnetic coupling between the main line and the sub line. The strength of the electromagnetic coupling between the main line and the sub line is mainly performed by adjusting the distance between the main line and the sub line. Adjustment of the distance between the main line and the sub line can be performed by the number of insulating layers interposed between the two.

  However, in the above-described conventional technology, the degree of coupling of the directional coupler is adjusted stepwise by the number of insulating layers interposed between the main line and the sub line, so that it is difficult to finely adjust the degree of coupling. There was a point. In this case, for example, it is difficult to set the desired degree of coupling in the directional coupler as the center value.

A directional coupler according to one aspect of the present invention is provided between a laminate including a plurality of insulating layers stacked on one another and layers of the plurality of insulating layers, and a part of the plurality of insulating layers is interposed between And a plurality of insulating layers between the first line and the second line on a part of the coupling line including the first line and the second line opposed to each other in the longitudinal direction of the coupling line. Between the first line and the second line with a part of the plurality of insulating layers interposed therebetween, and electrically connected to one of the first line and the second line. And an auxiliary coupled line including a connected third line , wherein the third line is disposed between layers of the plurality of insulating layers different from other parts in a portion of the length direction of the third line. that contains a moiety that is.

  A high frequency module according to one aspect of the present invention includes the directional coupler configured as described above and a circuit to which the directional coupler is electrically connected.

According to the directional coupler of one aspect of the present invention, having the above configuration, the electromagnetic coupling strength between the first line and the second line of the coupled line is set to the first line and the first line. In addition to direct electromagnetic coupling with the second line, electromagnetic coupling between the third line electrically connected to one of them (for example, the first line) and the other (for example, the second line) is also possible. The degree is adjusted. Therefore, the strength of the electromagnetic coupling between the first line and the second line can be adjusted more finely and continuously than in the prior art depending on the position and length of the third line. Therefore, it is easy to adjust so as to continuously change the strength of the electromagnetic coupling between the first line and the second line, and the accuracy of the adjusted degree of coupling is high. In addition, since the portions disposed between different layers are also electromagnetically coupled to the second line, the second line can be more finely adjusted with respect to the strength of the signal to be transmitted, and the adjusted coupling The accuracy of the degree will be even higher. This makes it possible, for example, to easily provide a directional coupler in which the desired degree of coupling is set to the center value.

  Since the high frequency module of one aspect of the present invention includes the directional coupler of the above configuration, continuous adjustment of the degree of coupling is easy, and a high frequency module with high accuracy of the adjusted degree of coupling is provided. Can.

It is sectional drawing which shows the principal part in the directional coupler of embodiment of this invention. It is a disassembled perspective view which shows typically the principal part in the high frequency module containing the directional coupler shown in FIG. It is a circuit diagram which shows typically the principal part in the high frequency module containing the directional coupler shown to FIG. 1 and FIG. It is sectional drawing which shows the modification of the directional coupler shown in FIG.

  The directional coupler and the high frequency module of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a cross-sectional view showing the main parts of a directional coupler according to an embodiment of the present invention. FIG. 2 is an exploded perspective view schematically showing the main part of the high frequency module including the directional coupler shown in FIG. FIG. 3 is a circuit diagram schematically showing the main part of the high frequency module including the directional coupler shown in FIGS. 1 and 2. The distinction between upper and lower in the following description is for convenience of explanation, and does not specify the upper and lower when a directional coupler or the like is actually used.

  In the directional coupler 10 of the embodiment, a plurality of insulating layers 11 are stacked to form a stacked body 1. The laminate 1 has, for example, a rectangular plate shape, and each has a rectangular (rectangular) upper surface and a lower surface.

  The first line 2 is provided between one of the plurality of insulating layers 11. In addition, the second line 3 is provided between the other layers. The first line 2 and the second line 3 face each other with parts of the plurality of insulating layers 11 interposed therebetween. In the example of FIG. 1, the insulating layer 11 on the upper side of the first line 2 and the lower side of the second line 3 are shown in order to clearly show only the positional relationship between the first line 2 and the second line 3 The insulating layer 11 is schematically indicated by a broken line. In practice, for example, as shown in FIG. 2, the insulating layer 11 is also stacked on the upper side of the first line 2 and the lower side of the second line 3.

The first line 2 and the second line 3 are electromagnetically coupled to each other to form a coupled line 4 in the directional coupler 10. One of the first line 2 and the second line 3 is a main line through which a signal is transmitted, and the other is an auxiliary line through which information for feedback obtained by electromagnetic induction according to the signal is transmitted. It is a track. In the present embodiment, the case where the first line 2 is a main line and the second line 3 is a sub-line will be described as an example. Details of the main line and the secondary line will be described later.

  The directional coupler 10 is basically formed of the above-described stack 1 and the coupling line 4. Also, the high frequency module 20 is basically formed by the directional coupler 10 and a circuit including the power amplifier to which the directional coupler 10 is electrically connected, the switch (SW), the antenna (ANT) and the like. .

  The stacked body 1 functions as an insulating base for providing the first line 2 and the second line 3 in a state of being electrically isolated from each other. The insulating substrate may include, in addition to the laminate 1, additional portions (not shown) such as other insulating layers or coating layers.

  The other insulating layer or the like as the additional portion may be, for example, the same as the insulating layer 11, and the insulating layer 11 is an electrical characteristic such as relative permittivity or relative permeability or a thermal characteristic such as thermal conductivity The characteristics may be different.

  The insulating layer 11 may be, for example, a ceramic sintered body such as an aluminum oxide sintered body, a glass ceramic sintered body, an aluminum nitride sintered body, a mullite sintered body, a silicon nitride sintered body, or a silicon carbide sintered body. It is formed of a binding material.

  The laminated body 1 is manufactured as follows, for example, if each insulating layer 11 is made of a glass ceramic sintered body. First, an appropriate organic binder, a solvent, and the like are added to and mixed with raw material powder comprising glass powder such as borosilicate glass and ceramic powder such as aluminum oxide to prepare a slurry. Next, the slurry is formed into a sheet by a forming method such as a doctor blade method to prepare a plurality of ceramic green sheets. Thereafter, the ceramic green sheets are cut and punched into appropriate shapes and laminated. Finally, the laminated body 1 can be manufactured by firing the laminated ceramic green sheets at a temperature of about 900 to 1000 ° C. in a reducing atmosphere.

  In the directional coupler 10 of this embodiment, a terminal 8 electrically connected to the coupling line 4 by a through conductor 7 (so-called via conductor) penetrating a part of the insulating layer 11 in the thickness direction is provided. . The directional coupler 10 and the circuit described above are electrically connected to each other through the terminal 8.

  Further, on the upper surface and the lower surface of the laminate 1, a ground conductor layer 9 electrically independent of the terminal 8 is provided. The ground conductor layers 9 face each other with the laminate 1 interposed therebetween. The pair of ground conductor layers 9 provided on the first and second main surfaces of the laminate 1 has a function of reducing transmission and reception of electromagnetic noise between the coupling line 4 and the auxiliary coupling line 6 and the outside. Have.

  Further, the ground conductor layer 9 has a function of adjusting the characteristic impedance (hereinafter, simply referred to as impedance) of the first line 2 and the second line 3 to a predetermined value. An electrostatic capacitance is generated between each of the first line 2 and the second line 3 and the ground conductor layer 9, and the impedance value of the first line 2 and the second line 3 is predetermined according to the magnitude of the electrostatic capacitance. Has been adjusted to the value of. The insulating layer or the like as the additional portion described above may be an insulating coating layer (not shown) for protecting the ground conductor layer 9 from the outside air to suppress oxidation and the like.

The through conductor 7, the terminal 8 and the ground conductor layer 9 are formed of, for example, a metal material of a metal material such as copper, silver, palladium, platinum, platinum, tungsten, molybdenum or manganese, or an alloy containing these metal materials. These metal materials are provided on the upper and lower surfaces of the laminate 1 in the form of a metallized layer or a plated layer.

  In the case where the terminal 8 and the ground conductor layer 9 are made of, for example, a metallized layer of copper, a metal paste prepared by kneading copper powder with an organic solvent and a binder is made into a laminate 1 to be a predetermined ceramic green sheet. It can be made to adhere to the 1st and 2nd principal surface of layered product 1, by printing by methods, such as screen printing, and calcinating a part.

  The through conductor 7 is formed by providing a through hole penetrating in the thickness direction in the ceramic green sheet to be the insulating layer 11, filling the through hole with the same metal paste as described above, and firing the same. be able to. The formation of the through holes in the ceramic green sheet can be performed by, for example, a mechanical punching method or a processing method such as an etching method.

  In the present embodiment, the ground conductor layer 9 is provided (in a so-called solid shape) so as to cover substantially the entire first and second main surfaces of the laminate 1. However, the ground conductor layer 9 does not necessarily have to cover substantially the entire upper and lower surfaces of the laminate 1, and the location of other conductors such as the terminals 8 or other design conveniences, or productivity, Depending on the economy and the like, a non-formed portion (a so-called cut portion of a pattern) may be provided as appropriate.

  For example, as shown in FIG. 3, in the directional coupler 10, both ends of each of the first line 2 and the second line 3 are electrically connected to the terminal 8, and through the terminal 8, a switch (SW), a filter It is electrically connected to a circuit included in a circuit component such as an element, an antenna (ANT), or a semiconductor integrated circuit element (IC). The high frequency module 20 according to the embodiment of the present invention is formed by the directional coupler 10 and the circuit included in the circuit component. The connection circuit for electrically connecting the circuit components and the directional coupler 10 is generally set to 50Ω.

  In the high frequency module 20, the directional coupler 10 and the circuit component are mounted on a substrate such as a printed circuit board, for example. The circuits such as the switch, the filter element, and the antenna may be configured by an electric circuit directly provided on the substrate. That is, the substrate on which the directional coupler 10 is mounted may have a circuit that functions as a switch or a filter and a circuit that connects circuit components mounted on the substrate. The electrical connection between the directional coupler 10 and the circuit components and the substrate is performed, for example, by connecting the respective connection portions with a conductive connection material such as solder.

  The high frequency module 20 is, for example, an integral part of a multiband circuit in a mobile phone. By using such a high frequency module 20 as a component, it becomes easier to achieve high functionality and the like including improvement of transmission / reception accuracy of devices such as mobile phones.

  In the directional coupler 10 and the high frequency module 20 according to the embodiment, the first line 2 and the second line 3 provided between the plurality of insulating layers 11 mutually sandwich a part of the plurality of insulating layers 11 therebetween. The coupled lines 4 are formed facing each other. In other words, in planar perspective, the first line 2 and the second line 3 overlap each other at least in part in the width direction.

  A signal is transmitted from a circuit such as SW through one terminal 8 to the first line 2 (main line), and power is transmitted from the first line 2 (main line) through the terminal 8 opposite to the one terminal 8 A signal is transmitted to a circuit such as an amplifier. The signal is, for example, a signal for communication in a mobile phone.

  More specific functions and the like of the directional coupler 10 and the coupling line 4 in the high frequency module 20 described above are, for example, as follows.

  The first line 2 is, for example, a signal line for inputting a high frequency signal amplified by a power amplifier and outputting the signal to a switch for switching between transmission and reception or a communication band or a filter for removing harmonics of the high frequency signal. The signal output from the directional coupler 10 is, for example, filtered by a filter to a predetermined frequency band, and then transmitted to the antenna and transmitted from the antenna to the outside. The antenna is, for example, an antenna of a mobile phone or the like.

  The second line 3 is electromagnetically connected to the first line 2. A feedback signal is transmitted from the second line 3 to the IC or the like using this electromagnetic connection. This signal is processed by an IC or the like, and the signal level transmitted through the first line 2 is monitored. That is, the signal level transmitted through the first line 2 is sent via the second line 3 to the IC that compares the signal levels. In this IC, for example, when the signal level inputted is lower than the set signal level, feedback is performed to raise the output level to the power amplifier, and when the signal level is high, the feedback is reversed. In this case, the degree of coupling in the directional coupler 10 is a value proportional to the ratio of the strength of the signal output from the second line 3 to the IC or the like to the strength of the signal input to the first line 2. The signal output from the second line 3 increases as the degree of coupling increases, and the signal output from the second line 3 decreases as the degree of coupling decreases.

  In addition, a signal in the opposite direction to the first line 2 (main line) is transmitted to the second line 3 (secondary line) by electromagnetic induction accompanying the transmission of a signal in the first line 2 (main line). The signal transmitted through the second line 3 (sub line) is, for example, information for feedback or the like. The signal transmitted through the second line 3 (sub line) is transmitted through one terminal 8 to an IC (semiconductor integrated circuit element) that processes information such as feedback information, and the IC performs predetermined processing. .

  Further, an end of the second line 3 (sub-line) opposite to the end electrically connected to the IC is electrically connected to a termination resistor through the terminal 8 and termination processing is performed. Specifically, the end of the second line 3 opposite to the end connected to the IC is connected to the termination resistor through the terminal 8. The termination resistance performs termination processing on the signal transmitted through the second line 3. In this case, the resistance value of the termination resistance is set to, for example, the same degree as that of the IC. The termination resistor may be an independent circuit component such as a ceramic chip resistor component, and comprises a resistor circuit (printed circuit or the like) formed on a printed circuit board or the like included in the high frequency module 20 including the directional coupler 10. It may be one.

  In the directional coupler 10 and the high frequency module 20 according to the embodiment, a plurality of the first line 2 and the second line 3 are provided between the first line 2 and the second line 3 in part of the length direction of the coupled line 4 (for example, the first line 2). A third line 5 is provided between the insulating layers 11. The third line 5 faces the first line 2 and the second line 3 with a part of the plurality of insulating layers 11 interposed therebetween, and is electrically connected to the first line 2. The third line 5 is for adjusting the degree of coupling in the directional coupler 10 as described later, and is electrically connected to any one of the first line 2 and the second line 3. It is good. In the present embodiment, an example in which the third line 5 is electrically connected to the first line 2 (main line) as described above will be described.

Since the directional coupler 10 has the above configuration, the strength of the electromagnetic coupling between the first line 2 and the second line 3 of the coupled line 4 can be expressed by the first line 2 and the second line 3. And the third line 5 electrically connected to one of them (the first line 2 in the present embodiment) and the other (the second line 3 in the present embodiment). Even electromagnetic coupling can be adjusted. Therefore, the strength of the electromagnetic coupling between the first line 2 and the second line 3 can be adjusted more finely than before by the position and the length of the third line 5. Therefore, for example, it is easy to continuously change the strength of the electromagnetic coupling between the first line 2 and the second line 3 and the accuracy of the adjusted degree of coupling is high. Thereby, for example, it is possible to provide the directional coupler 10 in which it is easy to set the desired degree of coupling to the center value.

  Further, according to the high frequency module 20 of the embodiment, since the directional coupler 10 having the above configuration is included, continuous adjustment of the degree of coupling is easy, and the high precision of the adjusted degree of coupling is high. Can be provided.

  The electrical connection between the first line 2 and the third line 5 is also made by the through conductor 7 (via conductor) penetrating the insulating layer 11 in the thickness direction. The through conductor 7 for electrically connecting the first line 2 and the third line 5 is also, for example, a metal material such as copper, silver, palladium, platinum, tungsten, molybdenum or manganese, or an alloy containing these metal materials. Is formed of a metal material of For example, a through hole penetrating in the thickness direction is provided in the ceramic green sheet to be the insulating layer 11, and the same metal paste as described above is filled in the through hole, and the through conductor 7 is formed by firing. Can.

  The first line 2, the second line 3 and the third line 5 are made of, for example, the same metal material as the ground conductor layer 9, that is, a metal material such as copper, silver, palladium, platinum, tungsten, molybdenum or manganese or It is formed of the metallic material of the alloy containing a metallic material. These metal materials are formed between the plurality of insulating layers 11 as a metallized layer, for example, by co-firing with the laminate 1.

  For example, if the first line 2, the second line 3 and the third line 5 are made of a metallized layer of copper, the insulating layer 11 is prepared by kneading a copper powder with an organic solvent and a binder. The main surface of the ceramic green sheet is printed by screen printing or the like in a linear pattern or the like, and co-fired to form it between the insulating layers 11 (that is, inside the laminate 1). it can.

  The degree of coupling in the directional coupler 10 basically depends on the length between the first line 2 (main line) and the second line 3 (secondary line) with the insulating layer 11 and the distance between the two. Adjusted. Specifically, the degree of coupling increases as the length of the opposing lines across the insulating layer 11 of the first line 2 (main line) and the second line 3 (subline) increases. The smaller the distance between the first line 2 (main line) and the second line 3 (sub line), the larger the degree of coupling.

  Among these conditions, the lengths of the first line 2 and the second line 3 are the desired size reduction as the laminate 1 (that is, the directional coupler 10), and the wiring conductors other than the coupling line 4 (shown in FIG. The degree of freedom in setting is relatively small because of restrictions such as the placement of Further, the distance between the first line 2 and the second line 3 is restricted to setting of so-called stepwise values by adjusting the number of layers of the insulating layer 11 in units of the thickness of the insulating layer 11.

  On the other hand, in the directional coupler 10 of the embodiment, since the auxiliary coupling line 6 including the third line 5 is provided, the strength of the electromagnetic coupling between the first line 2 and the second line 3 Is easy to change continuously.

  In this case, the third line 5 can be regarded as part of the main line electromagnetically coupled to the second line 3. Similar to the relationship with the first line 2, a signal is generated and transmitted to the second line 3 by electromagnetic induction also between the third line 5 and the second line 3. As for the third line 5, as in the first line 2, the longer the length facing the second line 3 and the smaller the distance to the second line 3, the degree of coupling in the directional coupler 10 large.

For the third line 5, in a range in which the first line 2 and the second line 3 face each other, variously adjust the length of the second line 3 and the distance between the second line 3 and each other. Can.
Therefore, the degree of coupling can be finely adjusted. In other words, the degree of coupling in the directional coupler 10 is adjusted to a substantially predetermined value by the coupling line 4 including the first line 2 and the second line 3, and the auxiliary coupling line 6 including the third line 5. Fine adjustments can be made by Therefore, the directional coupler 10 of the embodiment has a high degree of coupling accuracy.

A specific example of the setting of the degree of coupling in the directional coupler 10 will be described. In this example. The insulating layer 11 is made of a glass ceramic sintered body containing borosilicate glass and aluminum oxide and has a thickness of about 100 μm, and the first line 2, the second line 3 and the third
The lines 5 were each set to have a width of about 100 μm made of copper. Three insulating layers 11 are interposed between the first line 2 and the second line 3, and the lengths of the first line 2 and the second line 3 opposed to each other with the insulating layer 11 interposed therebetween are Each was set to about 5 mm. The third line 5 is provided in a layer immediately below the layer in which the first line 2 is provided, and both ends thereof are electrically connected to the first line 2 by the through conductor 7 made of copper. The frequency of the signal was set to about 900 MHz. At this time, when the length of the third line 5 was changed from 1 mm to 3 mm, the degree of coupling could be changed from 20.7 dB to 19.7 dB. When the length of the third line 5 is at the center of the above range, the coupling degree is also at the center of the above range. Incidentally, assuming that the third line 5 is not provided in the above specific example, the degree of coupling is a step according to the number of layers of the insulating layer 11 interposed between the first line 2 and the second line 3. Adjusted to the shape. That is, if the distance between the second line 3 and the third line 5 is about 50 μm (one intervening insulating layer 11 is one), the degree of coupling is about 14.9 dB, and the number of intervening layers is increased by one. The degree of coupling decreases stepwise by about 3.4 dB each time.

  FIG. 4 is a cross-sectional view showing a modification of the directional coupler 10 shown in FIG. The same reference numerals as in FIG. 1 denote the same parts in FIG. In the example shown in FIG. 4, the third line 5 includes a portion disposed between layers of a plurality of insulating layers 11 different from other portions in a part in the length direction. In this example, it may be regarded as an example in which a fourth line 5B interposed between the third line 5A and the second line 3 is further provided under the third line 5A provided in one layer. Can. In the following description, for convenience, a portion provided between one of the layers of the third line 5 is referred to as a third line 5A, and a portion provided between different layers is referred to as a fourth line 5B. That is, the combination of the third line 5A and the fourth line 5B in the following description corresponds to the third line 5 in the above embodiment.

  In this example, in the auxiliary coupling line 6, in addition to the third line 5A, the fourth line 5B is also electromagnetically coupled to the second line 3. By electromagnetically coupling the fourth line 5B and the second line 3, the intensity of the signal transmitted through the second line 3 can be more finely adjusted. Thus, in this case, it is possible to provide the directional coupler 10 and the high frequency module 20 with higher accuracy of the adjusted coupling degree.

  The electrical connection between the third line 5A and the fourth line 5B can be made, for example, by the through conductor 7 similarly to the electrical connection between the first line 2 and the third line 5 in the above embodiment. . Also for the through conductor 7 that electrically connects the third line 5A and the fourth line 5B, the same metal material as the through conductor 7 that electrically connects the first line 2 and the third line 5 is used similarly It can be formed by the method of

  The directional coupler and the high frequency module of the present invention are not limited to the examples of the above embodiments, and various modifications are possible within the scope of the present invention. For example, the third line 5 may be electrically connected to the second line 3 (not shown). In addition, two third lines may be provided, and they may be electrically connected to the first line 2 and the second line 3 one by one (not shown).

1 ・ ・ ・ Laminated body
11 ··· Insulating layer 2 · · · First line 3 · · · Second line 4 · · · Coupled line 5 · · · Third line 5A · · · Third line 5B · · · · Fourth line 6 · · · Auxiliary coupling line 7 · · · Through conductor 8 · · · Terminal 9 · · · Ground conductor layer
10 ··· Directional coupler
20 ・ ・ ・ ・ High frequency module

Claims (2)

A stack including a plurality of insulating layers stacked on one another;
A coupled line including a first line and a second line which are provided between layers of the plurality of insulating layers and face each other with a portion of the plurality of insulating layers interposed therebetween;
It is provided between layers of the plurality of insulating layers between the first line and the second line in a part in the length direction of the coupled line, and a part of the plurality of insulating layers is interposed therebetween. And an auxiliary coupled line including a third line opposed to the first line and the second line and electrically connected to one of the first line and the second line,
The third line is a directional coupler, characterized in Rukoto include a portion that is disposed between layers of the plurality differ from other portions of the insulating layer in a portion of the length direction of the third line . A directional coupler according to claim 1;
And a circuit electrically connected to the coupler.