JP2009212263A - Electronic circuit module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic circuit module, can suppress the cost of isolation countermeasures between electronic circuits or circuit blocks, while being capable of attaining isolation between the electronic components or the circuit blocks using a simple configuration and easily miniaturizing the module. <P>SOLUTION: The electronic circuit module 1 includes an insulating board 2, a plurality of electronic components loaded on the insulating board 2 and a ground electrode formed to the insulating board 2. In the electronic circuit module, a plurality of shielding chip components 5, connected to the ground electrode respectively, are arranged between the electronic components requiring at least isolation out of a plurality of electronic parts loaded on the insulating board 2 or between the circuit blocks 3 and 4 composed of a plurality of electronic components. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electronic circuit module in which an electronic component requiring isolation or a circuit block composed of a plurality of electronic components such as a transmission circuit and a reception circuit is mounted on the same substrate.

Conventionally, in an electronic circuit module that transmits and receives a high-frequency signal, measures against isolation are mainly provided between a transmission circuit and a reception circuit. For example, the arrangement positions of the transmission circuit and the reception circuit mounted on the same substrate are physically separated, or a plurality of partition plates for electromagnetic shielding are provided between the transmission circuit and the reception circuit (for example, Patent Document 1 or Patent Document 2).
Japanese Patent Laid-Open No. 11-274970 JP 2000-269678 A

  By the way, recent transmitters and receivers such as mobile phones are required to be downsized. Accordingly, it is necessary to downsize an electronic circuit module equipped with a transmitter / receiver circuit and the like. In this case, if a plurality of partition plates are provided between the transmission / reception circuits and other circuit blocks as in the prior art, these partition plates prevent the electronic circuit module from being downsized, and the electronic components or circuit blocks are connected to each other. Since it is necessary to form an opening for the connection connector for connecting to the partition plate, there is a problem that an electromagnetic shield such as a transmission / reception circuit cannot be easily realized. Furthermore, since it is necessary to change the processing jig used for the processing of the partition plate in accordance with different parts and layouts depending on the product to be mounted, there is a problem that the manufacturing cost increases.

  The present invention has been made in view of the above points, and can suppress the cost for measures against isolation between electronic components or circuit blocks, and can achieve isolation between electronic components or circuit blocks with a simple configuration. An object of the present invention is to provide an electronic circuit module that can be easily downsized.

  The electronic circuit module of the present invention is an electronic circuit module comprising an insulating substrate, a plurality of electronic components mounted on the insulating substrate, and a ground electrode formed on the insulating substrate. A plurality of shielding chip components respectively connected to the ground electrode are arranged between electronic components that require at least isolation among a plurality of electronic components mounted on the circuit block or between circuit blocks constituted by a plurality of electronic components. It is characterized by.

  According to this configuration, since the shielding chip parts maintained at the ground potential are arranged at least between the electronic parts or circuit blocks that require isolation, a simple shield wall is formed between them, and the partition plate Isolation can be achieved without providing an electronic circuit module, and the electronic circuit module can be downsized. Moreover, since it is not necessary to provide a plurality of partition plates for electromagnetic shield as in the conventional case, the cost for providing the shield can be suppressed.

  According to the present invention, in the electronic circuit module, the shielding chip component is a multilayer chip capacitor in which electrodes are stacked with a dielectric interposed therebetween, and at least one electrode of the multilayer chip capacitor is connected to the ground electrode. It is preferable.

  In this case, in the multilayer chip capacitor, since a large number of electrodes sandwiching a dielectric are stacked at a narrow interval, the electromagnetic shielding effect can be further enhanced. Note that both electrodes of the multilayer chip capacitor may be connected to the ground electrode.

  According to the present invention, in the electronic circuit module, the first circuit block is a transmission circuit that transmits a high-frequency signal, and the second circuit block is a reception circuit that receives the high-frequency signal. The shielding chip component is arranged at a boundary portion with the RF portion of the circuit.

  As a result, the signal chip interference can be effectively suppressed by arranging the shielding chip parts at locations where interference is likely to occur even within the module, such as the boundary between the RF section of the transmission circuit and the RF section of the reception circuit.

  The present invention, in the electronic circuit module, having a metallic cover that covers the electronic component mounted on the insulating substrate and the shielding chip component, the gap between the shielding chip component and the metallic cover, It is preferable that the wavelength is shorter than a quarter wavelength in air when a signal propagating through the first and second circuit blocks is emitted.

  In this case, since the distance between the shielding chip part and the facing surface of the metallic cover is ¼ or less of the wavelength of the signal frequency, the signal is transmitted from the gap between the shielding chip part and the facing surface of the metallic cover. Leakage can be further prevented.

  ADVANTAGE OF THE INVENTION According to this invention, while being able to suppress the cost for the countermeasure against isolation between electronic components or between circuit blocks, isolation can be aimed at without using a partition plate, and size reduction of a module can be achieved easily. .

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic diagram of an electronic circuit module according to an embodiment of the present invention. The electronic circuit module 1 shown in FIG. 1 is provided with a transmission circuit 3 and a reception circuit 4 serving as first and second circuit blocks on an insulating substrate 2. Between the transmission circuit 3 and the reception circuit 4, a plurality of shielding chip parts 5 are provided side by side so as to block the circuit blocks. The entire module including the transmission circuit 3 and the reception circuit 4, the shielding chip component 5, other circuit blocks and electronic components is covered with a metallic cover 10 shown in FIG. In the present embodiment, the electronic circuit module 1 will be described by taking a transmission / reception circuit module used in a transmission / reception circuit of a wireless communication device that transmits / receives a high-frequency signal as an example. However, any electronic circuit module that requires isolation can be applied.

First, the circuit configuration of the electronic circuit module 1 in the present embodiment will be briefly described.
FIG. 6 is a schematic circuit configuration diagram of the electronic circuit module 1 including the transmission circuit 3 and the reception circuit 4. The transmission circuit 3 mainly includes a transmission IC 32 having a modulation circuit 36 and a high frequency amplifier 37, a transmission filter 33 attached outside the IC, and a matching circuit 34. The matching circuit 34 is connected to the antenna via a terminal 35. A transmission signal is input to the modulation circuit 36 via the input terminal 31 from a transmission baseband IC (not shown). On the other hand, the reception circuit 4 is mainly composed of a reception IC 43 including a high frequency filter 42 connected to the antenna terminal 41, a low noise amplifier (LNA) 46, and a demodulation circuit 47, and a reception filter 44 attached outside the IC. Yes. The demodulated signal output from the demodulation circuit 47 is output to a receiving baseband IC (not shown) via the output terminal 45.

  2 and 3 are configuration diagrams of the electronic circuit module 1 according to the present embodiment. 2A is an external perspective view showing a state in which the circuit mounting surface of the electronic circuit module 1 according to the present embodiment is covered with a cover, and FIG. 2B shows the cover of the electronic circuit module 1. It is an external appearance perspective view which shows the state open | released. FIG. 3 is a plan view of the electronic circuit module 1 with the cover removed. In the following description, “upper”, “lower”, “left”, and “right” follow the directions shown in FIG.

  As shown in FIG. 2A, the electronic circuit module 1 includes a plurality of electronic circuit components (electronic components and circuit blocks) that require isolation on the main surface (upper surface) of the insulating substrate 2 having a substantially rectangular shape in plan view. A thin box-shaped metallic cover 10 is mounted so as to cover the entire main surface of the insulating substrate 2. The metallic cover 10 is formed in a substantially rectangular shape in plan view, and has a top plate 10 a formed in a size corresponding to the entire main surface of the insulating substrate 2, and a plurality (four) for fixing to the insulating substrate 2. Mounting portion 10b. The mounting portion 10b is bent into a substantially L shape from the vicinity of the corner of the top plate 10a toward the insulating substrate by bending, and is soldered to the fixed pattern 12 formed on the main surface of the insulating substrate 2. (See FIG. 4 described later). Thereby, the metallic cover 10 is connected to a ground pattern (described later) formed on the lower surface of the insulating substrate 2 through fixing to the insulating substrate 2, so that the metal cover 10 is made of a plurality of circuit components covered by the metallic cover 10. Electromagnetic waves to the outside of the conductive cover 10 and electromagnetic waves from the outside to the inside of the metallic cover 10 can be blocked.

  As shown in FIGS. 2B and 3, the plurality of IC circuits 3 and 4 and the electronic components 33, 34, 42 and 44 are mounted on the main surface 2 a which is the uppermost surface of the insulating substrate 2. On the main surface 2 a of the insulating substrate 2, the transmission circuit 3 and the reception circuit 4 are disposed so as to divide the region of the substrate 2 into two. The main surface 2a of the insulating substrate 2 is provided with various electronic components 15 such as a coil, a capacitor, and a resistor that are necessary for the circuit configuration.

  In the present embodiment, a plurality of functions that function as magnetic shield walls between a part of the matching circuit 34 and the transmission circuit 3 on the matching circuit side and a part of the reception filter 44 and the reception circuit 4 on the reception filter side. The chip components 5 for shielding are arranged. As will be described later, the terminals of the shielding chip component 5 are not connected to the hot side but are connected to the ground pattern. Note that the arrangement of the shielding chip parts 5 is not limited to the arrangement examples shown in FIGS. The arrangement state is not limited as long as the arrangement can achieve isolation between target electronic components or circuit blocks.

  4 is a cross-sectional view taken along line AA in FIG. As shown in FIG. 4, in this example, a multilayer chip capacitor in which a large number of electrodes are laminated at a narrow interval with a dielectric in between is used as the shielding chip component 5. The multilayer chip capacitor is preferably mounted on the main surface of the insulating substrate 2 so that the internal electrode stacking direction is perpendicular to the multilayer chip capacitor disposition direction. Isolation effect can be expected even in the installation direction. In the multilayer chip capacitor, at least one electrode is connected to the ground pattern 13 via the via 14. In the present embodiment, both electrodes of the multilayer chip capacitor are connected to the ground pattern 13 via the via 14. The ground pattern 13 becomes a ground electrode. As a result, the potential inside the multilayer chip capacitor becomes the same as the ground potential, so that the effect of preventing signal interference between the transmitting and receiving circuits can be enhanced.

  The insulating substrate 2 is formed with a plurality of external connection terminals for connecting to a mother board or the like, and via the vias 14 and the patterns formed on the main surface 2a of the insulating substrate 2 or the intermediate conductive layers 2b and 2c. It is configured to be electrically connectable.

  The distance D between the upper surface portion of the shielding chip component 5 and the facing surface of the metallic cover 10 facing the upper surface portion (the back surface of the top plate 10a) is determined by the transmission circuit 3 and the reception circuit of the electronic circuit module 1. It is preferable that the wavelength is shorter than a quarter wavelength in the air when a signal propagating 4 etc. is emitted. For example, if the target frequency band is 2010 MHz to 2025 MHz, the distance D may be 37 mm or less. Thereby, the leakage of the signal from the upper surface side of the electronic circuit module 1 can be suppressed, and interference between the transmission / reception circuits or other electronic components can be further prevented.

  As described above, according to the present embodiment, the shield chip component 5 connected to the ground pattern 13 is arranged between the transmission circuit 3 and the reception circuit 4 provided on the insulating substrate 2 to form a magnetic shield wall. Therefore, isolation between the transmission circuit 3 and the reception circuit 4 can be realized without providing a partition plate for magnetic shield. In addition, since there is no need to provide a partition plate, one obstacle to miniaturization of the electronic circuit module 1 can be removed, and an effect of facilitating miniaturization can be achieved. Further, when the shielding chip component 5 is constituted by a multilayer chip capacitor, the multilayer chip capacitor has a large number of electrodes sandwiching a dielectric, and the electromagnetic shielding effect is further improved. . Moreover, since it is used also as a circuit component of an electronic circuit module, it is not necessary to prepare a new shielding material as in the prior art, so that the cost for the shield can be suppressed. In addition, the degree of freedom of the circuit component mounting position and layout can be improved.

  The present invention is not limited to the above-described embodiment, and can be implemented with various modifications. In the above-described embodiment, the size, shape, and the like illustrated in the accompanying drawings are not limited thereto, and can be appropriately changed within a range in which the effect of the present invention is exhibited. In addition, various modifications can be made without departing from the scope of the object of the present invention.

  In the above embodiment, a plurality of shielding chip components 5 are arranged in a row in the short side direction of the insulating substrate 2 between the transmission and reception circuits. However, the present invention is not limited to this configuration. 5 may be arranged in a plurality of rows. In this case, as shown in FIG. 5, for example, the plurality of shield chip components 51 in the second row are preferably provided so as to be offset so as to fill the gaps between the plurality of shield chip components 5 in the first row. . Thereby, the shielding effect between transmission-and-reception circuits can further be improved. Further, since the interference between the matching circuit 34 on the transmission circuit 3 side and the reception filter 42 on the reception circuit 4 side is the most, the interval between the shielding chip parts 5 may be narrowed at a boundary portion or may be arranged in a plurality of rows. May be.

  Further, the shielding chip component 5 is not limited to the multilayer chip capacitor, and may be composed of other chip capacitors or chip inductors as long as the potential inside the component is maintained at the ground potential.

  The present invention can be applied to an electronic circuit module used in a small transceiver.

The schematic diagram which shows the principal part of the electronic circuit module which concerns on embodiment of this invention (A) External perspective view showing an electronic circuit module covered with a cover according to the present embodiment, (b) External perspective view showing an electronic circuit module with the cover opened. The top view which shows the electronic circuit module which concerns on the said embodiment Sectional view of the AA line of FIG. Schematic diagram showing the state in which multiple rows of shielding chip parts are arranged Circuit diagram of electronic circuit module according to the present embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electronic circuit module 2 Insulation board 3 Transmission circuit 4 Reception circuit 10 Metallic cover 13 Ground pattern (ground electrode)
32 Transmitting IC
33 Transmission Filter 34 Matching Circuit 36 Modulation Circuit 42 High Frequency Filter 43 Receiver IC
44 Receiving filter 46 Low noise amplifier (LNA)
47 Demodulator circuit

Claims (4)

An electronic circuit module comprising an insulating substrate, a plurality of electronic components mounted on the insulating substrate, and a ground electrode formed on the insulating substrate,
A plurality of shielding chip components respectively connected to the ground electrode between a plurality of electronic components which are mounted on the insulating substrate, between electronic components requiring isolation, or between circuit blocks composed of a plurality of electronic components. An electronic circuit module characterized by arranging the above.   The shield chip component is a multilayer chip capacitor in which electrodes are stacked with a dielectric interposed therebetween, and at least one electrode of the multilayer chip capacitor is connected to the ground electrode. The electronic circuit module according to 1.   The first circuit block is a transmission circuit that transmits a high-frequency signal, and the second circuit block is a reception circuit that receives a high-frequency signal, and at least at the boundary between the RF unit of the transmission circuit and the RF unit of the reception circuit The electronic circuit module according to claim 1, wherein the shielding chip parts are arranged.   When a signal propagating through the first and second circuit blocks is radiated at intervals between the electronic component mounted on the insulating substrate and the metallic cover that covers the shielding chip component and the shielding chip component The electronic circuit module according to claim 3, wherein the electronic circuit module is shorter than a quarter wavelength in the air.

Images