JP4193759B2 - Non-reciprocal circuit device and communication device - Google Patents

Description

  The present invention relates to a nonreciprocal circuit element, and more particularly to a nonreciprocal circuit element such as an isolator or a circulator used in a microwave band and a communication device including the element.

  Conventionally, nonreciprocal circuit elements such as isolators and circulators have a characteristic of transmitting power only in a predetermined specific direction and not transmitting in the reverse direction. Utilizing this characteristic, for example, an isolator is used in a transmission circuit unit of a mobile communication device such as a car phone or a mobile phone.

  As this type of non-reciprocal circuit element, Patent Document 1 discloses a capacitor element in which a central electrode made of a thin metal plate (copper foil) is disposed on a ferrite and a matching circuit is formed on a terminal substrate disposed on a lower surface of a lower yoke. And one end of the center electrode connected to the electrode of the capacitor element is disclosed. This non-reciprocal circuit element has a configuration in which the soldering strength of the center electrode, the capacitor element, etc. can be sufficiently obtained.

  By the way, in this non-reciprocal circuit element, it is necessary to process one end of the center electrode into a complicated shape for connection between the center electrode and the capacitor element and connection with the terminal electrode on the terminal substrate, Another member was used. However, such a configuration requires complicated sheet metal processing for the center electrode for connection, or requires another connection terminal and a resin case for pressing, which increases the number of parts and makes assembly difficult. However, there were problems that the cost was low and connection reliability could not be ensured.

In addition, the crossing angle of the center electrode is required to have a high accuracy of about ± 1 °. However, it is also costly to arrange the center electrode made of copper foil on the ferrite with high accuracy.
JP-A-7-263913

  Accordingly, an object of the present invention is to provide a non-reciprocal circuit element and a communication device that have a small number of components, have high connection reliability, and can achieve cost reduction.

In order to achieve the above object, a non-reciprocal circuit device according to a first invention is
From the upper side, a permanent magnet, a central electrode substrate provided with a plurality of central electrodes formed of an electrode film, a ferrite, yoke, a terminal substrate provided with an external connection electrode formed of an electrode film ,
A chip-shaped capacitor constituting a matching circuit is disposed between the central electrode substrate and the terminal substrate and outside the yoke , and an end of the central electrode and the external connection electrode are the capacitor are connected via the electrodes formed on both ends of,
The thickness of the capacitor is substantially equal to the combined thickness of the ferrite and the yoke;
It is characterized by.

In the nonreciprocal circuit device according to the first invention, a film resistance may be provided , and the film resistance can be formed on the center electrode substrate. Alternatively, a chip resistor may be used. This chip-like resistor may be disposed on the lower surface of the central electrode substrate, and the thickness is preferably thinner than the thickness of the ferrite. The chip resistor may be disposed on the upper surface of the terminal substrate and outside the yoke. A film resistor may be disposed outside the yoke.

  As for the center electrode substrate and the terminal substrate, both are preferably flat, and can be composed of a single-layer dielectric substrate, and the center electrode substrate and the terminal substrate have a copper film pasted on at least one surface. It is preferable to use a patterned electrode.

  A communication device according to a second aspect of the invention includes the nonreciprocal circuit element.

  According to the nonreciprocal circuit device according to the first invention, the capacitor constituting the matching circuit is disposed between the center electrode substrate and the terminal substrate, and the end of the center electrode provided on the center electrode substrate and the terminal substrate Since the external connection electrode provided on the capacitor is connected via the capacitor electrode, the connection between the center electrode and the external connection electrode is easy, and another member is required for the connection. Therefore, the number of parts is reduced, and the cost is reduced and the connection reliability is improved.

  In particular, if a plurality of center electrodes are formed of electrode films on a center electrode substrate, the crossing angle can be formed with high accuracy and at low cost. In addition, if the external connection electrode is formed on the terminal substrate with an electrode film, the number of parts is reduced and the number of assembling steps is reduced. Further, if one end of the center electrode is electrically connected directly to the yoke, the connection of the center electrode to the ground can be ensured without complicating the connection structure.

  On the other hand, the effect of the present invention can be satisfactorily achieved by using a chip-shaped capacitor in which electrodes are formed at both ends as a capacitor constituting the matching circuit. In this case, if the thickness of the capacitor is made equal to the total thickness of the ferrite and the yoke, the capacitor can be disposed between the center electrode substrate and the terminal substrate without any gap. Even if the thickness of the capacitor is slightly larger than the combined thickness of the ferrite and the yoke, the capacitor can be easily assembled if it is attached to the yoke.

  Furthermore, if the resistor is formed as a film resistor on the center electrode substrate, the nonreciprocal circuit device can be further reduced in size. Alternatively, the resistor may be a chip-shaped resistor, and when the chip-shaped resistor is disposed on the lower surface of the central electrode substrate, if the thickness is made thinner than the thickness of the ferrite, the chip-shaped resistor and the yoke are short-circuited. Can be prevented. If the chip-like resistor is arranged on the upper surface of the terminal board and outside the yoke, the chip-like resistor is arranged outside the magnetic circuit, and even if the chip-like resistor is enlarged to improve the power resistance, The magnetic circuit itself does not increase in size and does not deteriorate the efficiency of the magnetic circuit.

  With respect to the center electrode substrate and the terminal substrate, if both are made flat, the substrate can be easily manufactured, and the nonreciprocal circuit device can be made more compact. If these are composed of a single-layer dielectric substrate and at least one surface of which is coated with a copper film to form an electrode pattern, there is no need to provide the electrode as a separate body. Can be miniaturized.

  The communication device according to the second invention is provided with the advantages of the non-reciprocal circuit device that the connection reliability is high and the cost is low.

  Embodiments of a nonreciprocal circuit device and a communication device according to the present invention will be described below with reference to the accompanying drawings. In addition, the same code | symbol is attached | subjected to the member which is common in each Example shown below, and the overlapping description is abbreviate | omitted.

(Refer 1st Example and FIGS. 1-4)
As shown in FIGS. 1 and 2, the nonreciprocal circuit device 1A according to the first embodiment is a lumped constant type isolator, and includes an upper yoke 10, a permanent magnet 20, first and second centers from above. A central electrode substrate 30 provided with electrodes 31, 32, etc., a ferrite substrate 45, a lower yoke 15, a ground electrode 65, and a terminal substrate 60 provided with through holes 61, 62, 63 functioning as external connection electrodes are stacked. ing. Capacitors 51 and 52 constituting a matching circuit are disposed between the central electrode substrate 30 and the terminal substrate 60, and a resistance film 55 for absorbing a signal in the reverse direction is formed on the central electrode substrate 30. .

  The upper yoke 10 and the lower yoke 15 are made of a ferromagnetic material such as soft iron, and the permanent magnet 20 includes the upper surface portion 11 and the side surface portion 12 of the upper yoke 10 and the bottom surface portion 16 and the side surface portion 17 of the lower yoke 15. And the central electrode substrate 30 and the ferrite 45 are housed so as to constitute a magnetic circuit.

  As shown in FIG. 3A, the center electrode substrate 30 is formed with a first center electrode 31 formed of two lines as an electrode film on the upper surface, and further includes a resistance film 55 and an intermediate connection. A working electrode 33 is formed. Further, as shown in FIG. 3B, which is a perspective view from the upper surface, a second center electrode 32 composed of two lines is formed on the lower surface as an electrode film, and a land 34a for the capacitor 51 is formed. Are formed on the other end of the second center electrode 32, and the intermediate connection electrodes 36, 37 having the lands 36a, 37a for the capacitor 52 are formed. Is formed.

  Through holes 41, 42 and 43 are also formed in the center electrode substrate 30. The through hole 41 is connected to one end of the first center electrode 31 on the upper surface side and is connected to the intermediate connection electrode 34 on the lower surface side. The through hole 42 is connected to the intermediate connection electrode 33 on the upper surface side and connected to one end of the first center electrode 31 via the resistance film 55, and one end of the second center electrode 32 and the intermediate connection electrode on the lower surface side. It is connected to the electrode 36. The through hole 43 is connected to the other end of the first center electrode 31 on the upper surface side and is connected to the intermediate connection electrode 37 on the lower surface side.

  The resistance film 55 is connected to one end of the first center electrode 31 and is connected to one end of the second center electrode 32 through the intermediate connection electrode 33 and the through hole 42. Instead of the resistance film 55, a chip type similar to the capacitors 51 and 52 may be used. In this case, the chip resistor is disposed on the lower surface of the central electrode substrate 30 between electrodes (not shown) drawn from the through holes 41 and 42 shown in FIG. Such a chip resistor is preferably thinner than the thickness of the ferrite 45. This is to prevent a short circuit between the chip resistor and the lower yoke 15.

  The terminal substrate 60 is formed with a ground electrode 65 and lands 66 and 67 on its upper surface, and through holes 61, 62 and 63 located on the end face, and a through hole 64 penetrating the upper and lower surfaces. Further, the same electrode pattern as the upper surface is formed on the lower surface of the terminal substrate 60. The through hole 61 is connected to the land 66 and functions as an external connection input / output terminal. The through hole 62 is connected to the land 67 and functions as an external connection input / output electrode. The through hole 63 is connected to the ground electrode 65 and functions as an external connection ground electrode. The plurality of through holes 64 connect the ground electrode 65 on the upper surface and the ground electrode on the lower surface.

  The capacitors 51 and 52 are each of a chip type, and are provided with electrodes 51a and 51b and electrodes 52a and 52b at both ends. These electrodes are formed so as to extend from both end faces of the chip to at least the upper and lower surfaces. One electrode 51 a of the capacitor 51 is soldered to the land 34 a of the center electrode substrate 30 and the land 66 of the terminal substrate 60, and the other electrode 51 b is land of the land 35 a of the center electrode substrate 30 and the ground electrode 65 of the terminal substrate 60. It is soldered to 65a. One electrode 52 a of the capacitor 52 is soldered to the land 36 a of the center electrode substrate 30 and the land 67 of the terminal substrate 60, and the other electrode 52 b is the land 37 a of the center electrode 30 and the land 65 b of the ground electrode 65 of the terminal substrate 60. It is soldered to and.

  The center electrode substrate 30 and the terminal substrate 60 provided with the above circuit elements are manufactured as follows. That is, these substrates 30 and 60 are manufactured as resin printed substrates. The resin used as the material is polyimide resin, glass epoxy resin, glass fluororesin, liquid crystal polymer resin, or the like. This kind of single-layer resin substrate is prepared as a mother substrate of about 4 to 8 inches square, and a copper film is formed on both sides of the mother substrate.

  The copper film on the mother substrate is etched to form the electrodes 31 to 37, 65 and the like in a predetermined pattern. Further, the through holes 41 to 43 and 61 to 64 are formed at predetermined positions and filled with a conductive paste, and these conductive pastes are baked. Thereafter, the resistance film 55 is printed on the center electrode substrate 30 and baked. The resistance film 55 is laser trimmed so as to have a predetermined resistance value. The center electrode substrate 30 is dicer cut or laser cut for each unit of about 3 mm square.

  Next, the capacitors 51 and 52 are soldered onto the lands 66 and 67 and the ground electrode 65 of the terminal board 60 in the mother board state, and the lower yoke 15 is soldered onto the ground electrode 65 of the terminal board 60. Further, the ferrite 45 is fixed on the bottom surface portion 16 of the lower yoke 15 with an adhesive. Further, the lands 34a, 35a, 36a, 37a of the center electrode substrate 30 that have already been cut to a predetermined size and the capacitors 51, 52 are soldered.

  The permanent magnet 20 is fixed to the center electrode substrate 30 and the upper surface of the upper yoke 10 with an adhesive, and applies a DC magnetic field to the ferrite 45. The upper yoke 10 and the lower yoke 15 are integrated with each other at the side surfaces 12 and 17 by a conductive adhesive. Thereafter, the terminal board 60 is dicer cut or laser cut for each unit of about 3 mm square.

  FIG. 4 shows an electrical equivalent circuit of the nonreciprocal circuit device (lumped constant type isolator) 1A assembled as described above. The through hole (external connection input / output electrode) 61 functions as the input port P1, and the through hole (external connection input / output electrode) 62 functions as the output port P2. The first center electrode 31 and the capacitor 51 constitute a parallel LC resonance circuit, and the second center electrode 32 and the capacitor 52 constitute a parallel LC resonance circuit. The resistance film 55 is inserted in series between the ports P1 and P2. The other ends of the center electrodes 31 and 32 and the capacitors 51 and 52 are connected to a through-hole (external connection ground electrode) 63.

  According to the nonreciprocal circuit device 1A described above, the first center electrode 31 and the second center electrode 32 are formed as electrode films on the upper and lower surfaces of the center electrode substrate 30, so that the crossing angle can be accurately determined and Can be formed at low cost. Moreover, since one end of the center electrodes 31 and 32 is connected to the through holes (input / output electrodes for external connection) 61 and 62 via the electrodes 51a and 52a of the capacitors 51 and 52, both are easily connected. In addition, no other member is required for connection, the number of parts is reduced, cost is reduced, and connection reliability is improved.

  Further, the center electrode substrate 30 and the terminal substrate 60 are both flat and easy to manufacture, and the nonreciprocal circuit element 1A is configured more compactly. In addition, since the substrates 30 and 60 are resin printed substrates, the center electrodes 31 and 32, the intermediate connection electrodes 33 to 37, the ground electrode 65, and the like can be easily formed by a method such as etching as described above. Can do.

  Further, since the through holes 41 to 43 and 61 to 64 are formed in the substrates 30 and 60 as intermediate connection electrodes and external connection input / output electrodes, the substrates 30 and 60 are separated from a large area mother substrate into a predetermined unit. In the first embodiment, which is cut out and manufactured, these electrodes are convenient, and these electrodes can be easily formed on the end faces of the substrates 30 and 60. The reason why the substrates 30 and 60 are made of resin is that a thin substrate having a thickness of about 100 μm can be obtained, and it has the advantage of being inexpensive and difficult to break. The substrates 30 and 60 may be made of ceramic.

  In addition, since the resistance film 55 is formed on the central electrode substrate 30 as a printed film, the number of parts is further reduced, and the nonreciprocal circuit element can be further reduced in size.

(Refer to the second embodiment, FIGS. 5 and 6)
As shown in FIGS. 5 and 6, the nonreciprocal circuit device 1 </ b> B according to the second embodiment has an intermediate connection in which a bent portion 18 is formed in the lower yoke 15 and the bent portion 18 is formed on the lower surface of the central electrode substrate 30. The electrode 37 and the second center electrode 32 are directly connected to the other end portions.

  Other configurations are the same as those of the non-reciprocal circuit device 1A according to the first embodiment, and the effects thereof are the same as those of the first embodiment.

  In particular, in the second embodiment, the other end of the first center electrode 31 is connected to the bent portion 18 of the lower yoke 15 via the intermediate connection electrode 37, and the other end of the second center electrode 32 is also connected to the other end. Since it is connected to the bent portion 18, the connection of the center electrodes 31 and 32 to the ground electrode 65 is more reliable without complicating the connection structure.

(Refer to the third embodiment, FIGS. 7 and 8)
As shown in FIGS. 7 and 8, the non-reciprocal circuit device 1C according to the third embodiment uses a chip resistor 56 instead of the resistance film 55, and the chip resistor 56 is an intermediate connection of the terminal substrate 60. Soldered onto the lands 86 a and 87 a of the electrodes 86 and 87 and disposed outside the lower yoke 15. That is, the electrode 56a of the chip resistor 56 is soldered to the land 86a, and the electrode 56b is soldered to the land 87a.

  Other configurations are the same as those of the non-reciprocal circuit device 1A according to the first embodiment. However, in the non-reciprocal circuit device 1C, the chip resistor 56 is disposed outside the lower yoke 15, and therefore the central electrode substrate 30 is provided. In addition, the electrode configuration of the terminal board 60 is changed as described below.

  That is, the first center electrode 31 is formed by two lines on the upper surface of the center electrode substrate 30. On the lower surface, the second center electrode 32 is formed by two lines, and the intermediate connection electrode 71 and the electrode 51b having a land 71a to which the electrode 51a of the capacitor 51 is soldered are soldered. An intermediate connection electrode 72 having a land 72a, an intermediate connection electrode 73 having a land 73a to which the electrode 52a of the capacitor 52 is soldered, and an intermediate connection electrode 74 having a land 74a to which the electrode 52b is soldered are formed. ing.

  Through holes 75 and 76 are formed at both ends of the first center electrode 31, and the through holes 75 are connected to the intermediate connection electrode 71 on the lower surface of the substrate 30. The through hole 76 is connected to the intermediate connection electrode 74 on the lower surface of the substrate 30. The intermediate connection electrode 72 is connected to the other end of the second center electrode 32, and the intermediate connection electrode 73 is connected to one end of the second center electrode 32.

  On the upper surface of the terminal substrate 60, a ground electrode 85 and intermediate connection electrodes 86, 87 are formed, and through holes 81, 82, 83 are formed. Furthermore, a ground electrode (not shown) is also formed on the lower surface of the terminal substrate 60. The through hole 81 is connected to the intermediate connection electrode 86 and functions as an external connection input / output electrode (input port P1). The through hole 82 is connected to the intermediate connection electrode 87 and functions as an external connection input / output electrode (output port P2). The through hole 83 is connected to the ground electrode 85 on the upper surface and the ground electrode on the lower surface, and functions as an external connection ground electrode.

  One electrode 51 a of the capacitor 51 is soldered to the land 86 b of the intermediate connection electrode 86 formed on the terminal substrate 60 and is also soldered to the land 71 a of the intermediate connection electrode 71 formed on the center electrode substrate 30. . The other electrode 51 b is soldered to a part 85 a of the ground electrode 85 on the terminal substrate 60 and is soldered to a land 72 a of the intermediate connection electrode 72 formed on the center electrode substrate 30.

  One electrode 52 a of the capacitor 52 is soldered to the land 87 b of the intermediate connection electrode 87 formed on the terminal substrate 60 and is also soldered to the land 73 a of the intermediate connection electrode 73 formed on the center electrode substrate 30. . The other electrode 52 b is soldered to a part 85 b of the ground electrode 85 on the terminal substrate 60 and soldered to a land 74 a of the intermediate connection electrode 74 formed on the center electrode substrate 30.

  The electrical equivalent circuit of the nonreciprocal circuit device 1C having the above configuration is the same as that shown in FIG. The function and effect are the same as in the first embodiment.

  In particular, in the third embodiment, since the chip resistor 56 is disposed outside the lower yoke 15, even if the chip resistor 56 is enlarged to improve the withstand voltage, the chip resistor 56 is located outside the magnetic circuit. The magnetic circuit itself does not increase in size and does not deteriorate the efficiency of the magnetic circuit. It is also possible to use a film resistor instead of the chip resistor 56.

(Communication device, see FIG. 9)
Here, a mobile phone will be described as an example of a communication device equipped with the nonreciprocal circuit element. FIG. 9 shows an electric circuit of the RF portion of the mobile phone 320. 322 is an antenna element, 323 is a plexer, 331 is a transmission side isolator, 332 is a transmission side amplifier, 333 is a band pass filter for transmission side stages, and 334 is transmission. The side mixer 335 is a reception side amplifier, 336 is a reception side interstage band pass filter, 337 is a reception side mixer, 338 is a voltage controlled oscillator (VCO), and 339 is a local band pass filter.

  Here, the nonreciprocal circuit elements (lumped constant type isolators) shown as the respective embodiments can be used as the transmission side isolator 331. By mounting these nonreciprocal circuit elements, a small and low-cost mobile phone can be realized.

(Other examples)
The nonreciprocal circuit device and the communication device according to the present invention are not limited to the above-described embodiments, and can be variously modified within the scope of the gist.

  For example, the detailed configuration of the center electrode substrate and the terminal substrate, in particular, the lead-out shape of the electrodes is arbitrary. Further, the configuration of the upper yoke and the lower yoke is also arbitrary.

1 is an exploded perspective view showing a first embodiment of a non-reciprocal circuit device according to the present invention. It is a front view which shows the said 1st Example. The center electrode board | substrate which comprises the said 1st Example is shown, (A) is a top view, (B) is a bottom view (state seen through from the upper surface). It is a block diagram which shows the electrical equivalent circuit of the said 1st Example. It is a disassembled perspective view which shows 2nd Example of the nonreciprocal circuit device based on this invention. It is a front view which shows the said 2nd Example. It is a disassembled perspective view which shows 3rd Example of the nonreciprocal circuit device based on this invention. It is a front view which shows the said 3rd Example. It is a block diagram which shows the electric circuit of the communication apparatus (cellular phone) which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1A-1C ... Nonreciprocal circuit element 10 ... Upper yoke 15 ... Lower yoke 20 ... Permanent magnet 30 ... Center electrode board | substrate 31 ... 1st center electrode 32 ... 2nd center electrode 45 ... Ferrite
51, 52 ... Capacitors 51a, 51b, 52a, 52b ... Capacitor electrodes 55 ... Resistive films 56 ... Chip resistors 60 ... Terminal boards 61, 62 ... Through holes (input / output electrodes for external connection)
63 ... Through hole (ground electrode for external connection)

Claims (9)

From the upper side, a permanent magnet, a central electrode substrate provided with a plurality of central electrodes formed of an electrode film, a ferrite, yoke, a terminal substrate provided with an external connection electrode formed of an electrode film ,
A chip-shaped capacitor constituting a matching circuit is disposed between the central electrode substrate and the terminal substrate and outside the yoke , and an end of the central electrode and the external connection electrode are the capacitor are connected via the electrodes formed on both ends of,
The thickness of the capacitor is substantially equal to the combined thickness of the ferrite and the yoke;
A nonreciprocal circuit device characterized by the above. The nonreciprocal circuit device according to claim 1 , further comprising a film resistor, wherein the film resistor is formed on the center electrode substrate. 2. The nonreciprocal circuit device according to claim 1 , further comprising a chip resistor, wherein the chip resistor is disposed on a lower surface of the center electrode substrate, and the thickness thereof is smaller than the thickness of the ferrite. 2. The nonreciprocal circuit device according to claim 1 , further comprising a film-like or chip-like resistor, wherein the resistor is disposed on the upper surface of the terminal substrate and outside the yoke. The nonreciprocal circuit device according to claim 1, wherein each of the center electrode substrate and the terminal substrate has a flat plate shape. 6. The nonreciprocal circuit device according to claim 5 , wherein each of the center electrode substrate and the terminal substrate is a single-layer dielectric substrate. The nonreciprocal circuit device according to claim 6 , wherein the central electrode substrate and the terminal substrate are formed by patterning electrodes by attaching a copper film on at least one surface. The nonreciprocal circuit device according to claim 1, wherein one end portion of the center electrode is electrically connected directly to the yoke. A communication apparatus comprising the nonreciprocal circuit element according to claim 1 .

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