JP2009232257A5 - - Google Patents

Description

Electronic circuit board, electronic circuit device, and power line communication device using the same

  The present invention relates to an electronic circuit board, an electronic circuit device, and a power line communication device using the same, and particularly a mounting structure in consideration of heat dissipation of a semiconductor integrated circuit used in an environment with severe noise countermeasures such as high-speed power line communication (PLC). About.

Along with the demand for miniaturization of electronic components, circuit modules equipped with semiconductor integrated circuits and circuit components must be equipped with a large number of integrated circuit chips and circuit components. The demand for is increasing.
In particular, since a signal used in the field of optical communication is a digital signal, an analog circuit connected to the output of the light receiving element and a digital circuit mounted for the purpose of synchronizing the received signal are mixedly mounted. For this reason, there is a problem that the characteristics of the analog circuit are deteriorated due to noise generated in the digital circuit, and various countermeasures have been conventionally considered.

As an example, there has been proposed a structure in which an analog circuit is disposed on one surface and a digital circuit is disposed on the other surface with a grounded conductor plate in between (Patent Document 1).
With this configuration, electromagnetic noise generated by the digital circuit is blocked by the conductor plate and does not reach the analog circuit, so that noise can be reduced. Further, since the double-sided mounting configuration is used, the apparatus can be downsized.

  Also, in multilayer circuit boards that are likely to be a source of unwanted radiation noise, the bypass capacitor power supply wiring area is narrowed so that the high frequency current generated from the IC power supply terminal does not pass through the bypass capacitor, or the IC power supply power supply The present applicant has proposed various structures such as a structure in which a pattern and a power supply pattern for external power supply are spatially separated (Patent Document 2).

In particular, in a modulation / demodulation IC that modulates and demodulates signals, a large number of ground terminals (pads) are arranged at a narrow pitch, and each ground terminal is connected on a mounting substrate. As the mounting substrate, a laminated substrate in which a plurality of wiring layers are laminated via an insulating layer is used (Patent Document 3).
In such a laminated substrate, in order to reduce the wiring routing as much as possible and reduce the impedance caused by the wiring itself, the power line and the ground line are usually formed in a plate shape in the wiring layer. Then, it is formed by embedding in the laminated substrate as a power supply plate and a ground plate.

JP-A-4-252624 JP 2003-297963 A Japanese Patent No. 3375555

  In recent years, in the PLC field, not only the planar occupation area but also the distance in the vertical direction cannot be overlooked, and the increase in the inductance due to the increase in the distance in the thickness direction of the multilayer substrate has become a problem. . Under such circumstances, the miniaturization of the wiring length is progressing, the miniaturization is progressing and not only the occupied area is about 60% of the conventional, but also the density of parts is greatly advanced, Unwanted radiation noise is a very serious problem.

  The present invention has been made in view of the above-described circumstances, and in further downsizing the device, increasing the arrangement of elements and increasing the density of wiring, the propagation of noise is suppressed, and a highly reliable electronic circuit board and the same are used. An object is to provide an electronic circuit.

Therefore, in the electronic circuit board of the present invention, a digital component including an integrated circuit for modulation / demodulation for performing digital signal processing is mounted on the first surface, and a predetermined value is provided on the second surface facing the first surface. A balanced filter that cuts off power line communication signals in the frequency band is mounted.
According to this configuration, the digital component is mounted on the first surface, the balanced filter is mounted on the second surface facing the first surface, and the second surface faces the mounting substrate. Therefore, the balanced filter can avoid the influence of noise from the digital component and can reduce noise.

In the electronic circuit device of the present invention, a digital component including an integrated circuit for modulation / demodulation for performing digital signal processing, a balanced filter for cutting off a power line communication signal in a predetermined frequency band, and the digital signal on the first surface A component is mounted, and a substrate on which the balanced filter and the external connection portion are mounted is provided on a second surface facing the first surface.
According to this configuration, the digital component is mounted on the first surface, the balanced filter is mounted on the second surface facing the first surface, and the second surface faces the mounting substrate. Therefore, the balanced filter can reduce the influence of noise from the digital component, can reduce noise, and can provide a highly reliable electronic circuit device.

  According to the present invention, in the electronic circuit device, the substrate includes a substrate formed of a laminated substrate having a plurality of conductive layers laminated via insulating layers. With this configuration, since the conductive layer provided inside the substrate shields noise generated from the digital component, it is possible to further reduce the influence of the noise received by the balanced filter mounted on the second surface.

According to the present invention, in the electronic circuit device, the substrate includes first and second substrates stacked via an insulating sheet, and is mounted on the first surface inside the insulating sheet. Including a built-in circuit component electrically connected to at least one of the digital components.
According to this configuration, by incorporating the circuit components, the interval between the digital components mounted on the first surface can be minimized, and wiring for connecting the digital components and the built-in circuit components is also possible. Can be embedded in the built-in part. By reducing the distance between the digital parts, the wiring length between the digital parts can be shortened, and the signal loop that causes the unnecessary radiation can be reduced. Therefore, unnecessary radiation can be reduced.

  According to the present invention, in the above electronic circuit device, at least one of the first and second substrates includes a laminated substrate having a plurality of conductive layers laminated via insulating layers. .

In the present invention, the electronic circuit device includes one in which at least two terminals of a digital component mounted on the first surface are connected via a resistor as the built-in circuit component.
According to this configuration, even if unnecessary radiation occurs due to mismatch between the characteristic impedance and resistance of the wiring, the resistance is a built-in circuit component. Can be trapped inside. Moreover, not only can the connection wiring between the digital components be built-in, but it can also be formed as an inner layer in the laminated substrate, facilitating wiring and reducing the wiring length.

According to the present invention, in the electronic circuit device, the digital component mounted on the first surface and the built-in circuit component are connected via a through via.
According to this configuration, the wiring is in a direction perpendicular to the substrate surface, and not only can the length be reduced, but even if unnecessary radiation occurs, it is propagated and emitted in the inner layer, and the electronic circuit device It is possible to reduce the influence of unnecessary radiation.

  According to the present invention, in the electronic circuit device, the analog component is mounted on the second surface, and the connection portion is provided on the second surface of the substrate and connected to the mounting substrate. including

According to the present invention, in the electronic circuit device, the first and second substrates include those thinner than the insulating sheet.
With this configuration, it is possible to reduce stress due to thermal expansion of the first and second substrates, and thus it is possible to suppress a decrease in bondability between the substrate and the insulating sheet.

According to the present invention, in the electronic circuit device, the analog component includes a heat generating component arranged so as to avoid a position facing the digital component in a plane.
With this configuration, the influence of heat transmitted through the substrate can be avoided.

According to the present invention, in the electronic circuit device, the heat generating component is an amplifier (op amp).
With this configuration, the operational amplifier generates a large amount of heat and is susceptible to noise, but avoids the effect of heat transmitted through the board because it is placed away from the position facing the digital component in a plane. can do.

In the present invention, the electronic circuit device includes a heat dissipating member that contacts the digital component.
According to this configuration, since the heat radiating member that comes into contact with the digital component is provided, the heat radiating member plays a role of forcibly releasing heat. For this reason, the heat from the digital component is efficiently radiated from the first surface of the substrate, and heat does not flow into the second surface, so that the influence of heat can be blocked.

According to the present invention, in the electronic circuit device, the first surface of the substrate is provided with a heat radiating member via an insulating elastic member.
With this configuration, the height of the component mounted on the first surface of the substrate can be absorbed by this elastic member, and the adhesion can be increased, so that the thermal contact property can be improved and the heat dissipation can be further improved. .

  In the present invention, in the electronic circuit device, the digital component includes one that performs at least one of a modulation process and a demodulation process of a multicarrier signal. Here, even an integrated circuit that performs both modulation and demodulation processing is effective.

According to the present invention, in the electronic circuit device, the multicarrier signal includes a power line communication signal that can be transmitted to a power line having a pair of lines.
According to this configuration, since the digital component that performs at least one of the modulation processing and the demodulation processing of the multicarrier signal is arranged on the surface opposite to the heat generating component, the influence of heat can be reduced.

In the present invention, the electronic circuit device may further include a filter that is mounted on the second surface and that blocks a predetermined frequency band for the power line communication signal. It is.
According to this configuration, the digital component that performs at least one of the modulation processing and the demodulation processing of the multicarrier signal and the filter are respectively mounted on different surfaces of the substrate and are shielded from each other by the substrate. It is possible to suppress the influence of noise caused by digital parts from reaching the filter. Further, by using a laminated substrate as the substrate, the shielding effect between the first surface and the second surface can be further enhanced. In addition, by using a laminated substrate composed of a plurality of conductive layers laminated via an insulating layer, a ground terminal and a ground layer can be connected without using a through via. Even when the mounting area of the filter is increased, both surfaces of the multilayer substrate can be efficiently used as mounting surfaces, and as a result, the electronic circuit device can be reduced in size.

In the present invention, in the electronic circuit device, the filter includes a balanced filter having substantially the same impedance as viewed from each of the pair of lines.
According to this configuration, it is possible to reduce the influence of noise on the balanced filter by mounting the balanced filter on the surface facing the digital component. Also, a balanced filter that is usually mounted with a combination of chip components such as a chip inductor and a chip capacitor tends to have a large mounting area. However, according to this configuration, the mounting area of the balanced filter used for power line communication is large. Even if it becomes, size reduction of an electronic circuit board can be achieved.

According to the present invention, in the electronic circuit device, the power line communication signal output from the electronic circuit device is superimposed on the AC voltage transmitted to the power line, and the power line communication signal is separated from the AC voltage transmitted to the power line. And a power line communication device including a coupler that outputs to the mounting board.
According to this configuration, it is possible to provide a power line communication device that can perform high-speed communication and has low noise and high reliability.

According to the present invention, in the electronic circuit device, the electronic circuit device further includes a plurality of conductive layers stacked via the insulating layer, and includes another stacked substrate different from the stacked substrate, and the other stacked substrate. A circuit element mounted on a surface; and a conductive path that is interposed between the multilayer substrate and the other multilayer substrate to laminate the multilayer substrate and electrically connects the integrated circuit and the circuit element. Including an insulating sheet.
With this configuration, it is possible to provide a small and low-noise electronic circuit device.

In the present invention, the electronic circuit device includes a built-in circuit element provided on the insulating sheet and built in the electronic circuit board, wherein the built-in circuit element is surrounded by the conductive path.
According to this configuration, it is possible to perform reliable shielding with a simple configuration by forming the conductive path with a conductive paste or the like. Moreover, you may make it cover with copper foil.

According to the present invention, in the electronic circuit device, the multilayer substrate and the other multilayer substrate include ones having the same substrate thickness.
According to this configuration, since the thicknesses of the substrates are configured to be equal, the two laminated substrates due to a difference in substrate thermal expansion during a temperature change such as a heat shock and the insulating sheet provided with the conductive path It is possible to prevent peeling and improve the connection reliability of the conductive path connecting the two laminated substrates.

According to the present invention, the electronic circuit device includes a built-in circuit element provided on the insulating sheet and built in the substrate, wherein the plurality of built-in circuit elements includes a thickness of the substrate and the other substrate. The one mounted on the thicker substrate.
According to this configuration, even if the substrate is thinned, circuit components are mounted only on the thicker substrate, so that the warp of the thin substrate is prevented, and two layers are laminated when laminated with an insulating sheet having a conductive path, that is, a composite sheet. It becomes possible to improve the connection reliability of the conductive path connecting the laminated substrates.

In the present invention, in the electronic circuit device, the insulating sheet includes an inorganic filler and a thermosetting resin.
According to this configuration, it is possible to control the thermal expansion coefficient, dielectric constant, and thermal conductivity by selecting an inorganic filler, improving the connection reliability of the conductive path connecting the two laminated substrates, and heat dissipation Can be improved.

In the present invention, in the electronic circuit device, the insulating sheet contains 70 wt% to 95 wt% of an inorganic filler and a thermosetting resin.
According to this configuration, the coefficient of thermal expansion can be matched with that of the two laminated substrates, and the two laminated substrates and the conductive material in the case of a temperature change such as a heat shock due to a difference in thermal expansion between the insulating sheet and the two laminated substrates. It is possible to prevent peeling from the insulating sheet provided with a path, and to improve the connection reliability of the conductive path connecting the two laminated substrates. In addition, when the insulating sheet and the two laminated substrates are laminated, the pressure applied to the circuit component mounted on the surface in contact with the insulating sheet can be suppressed, and damage to the circuit component can be prevented. The laminated substrate is formed by sandwiching an insulating layer between conductive layers on which a desired pattern is formed. This insulating layer can also be composed of an inorganic filler and a thermosetting resin. When this insulating sheet is made of a thermosetting resin having a lower curing temperature than the insulating layer constituting the laminated substrate, the insulating layers of the laminated substrate are heat-treated when the laminated substrates are fixed together via the insulating sheet. It is possible to prevent the deterioration.

According to the present invention, in the electronic circuit device, the connector is provided in the vicinity of one end of the substrate, and the heat generating component is provided at an end edge on a diagonal line with respect to the connection portion.
According to this configuration, since the heat generating component is provided at a position far from the connector, the heat from the heat generating component can be dissipated before reaching the connector. Further, by disposing a heat sink on the first surface side of the substrate, heat can be efficiently radiated.

  The present invention also includes a first substrate having a first surface and a second surface facing the first surface, on which a digital component for performing digital signal processing is mounted on the first surface. An analog component having a third surface facing the second surface of the first substrate and a fourth surface facing the third surface, and performing analog signal processing on the fourth surface; An electronic circuit board having a second substrate to be mounted, wherein the second surface of the first substrate and the third surface of the second substrate are arranged at a predetermined interval. .

  According to this configuration, the digital component is mounted on the first surface of the first substrate, the analog component is mounted on the fourth surface of the second substrate, and the second surface and the second surface of the first substrate are mounted. By providing a space between the third surface of the substrate and the distance between the digital component and the analog component increases, it is possible to reduce the influence of noise generated by the digital component on the analog component. An electronic circuit board can be realized.

  The present invention also includes a digital component that performs digital signal processing, an analog component that performs analog signal processing, a first surface, and a second surface that faces the first surface. A first board having the digital component mounted thereon, a third face facing the second face of the first board, and a fourth face facing the third face, A second substrate having the analog component mounted on a fourth surface, a second surface of the first substrate, and a third mounting surface of the second substrate are arranged at a predetermined interval. Electronic circuit device.

  According to this configuration, the digital component is mounted on the first surface of the first substrate, the analog component is mounted on the fourth surface of the second substrate, and the second surface and the second surface of the first substrate are mounted. By providing a space between the third surface of the substrate and the distance between the digital component and the analog component increases, it is possible to reduce the influence of noise generated by the digital component on the analog component. An electronic circuit device can be realized.

  The present invention is the above electronic circuit device, wherein at least one of the first substrate and the second substrate is formed of a laminated substrate having a plurality of conductive layers laminated via insulating layers therein. Including

  With this configuration, the conductive layer provided inside the substrate shields noise generated from the digital component, so that the influence of the noise received by the analog component mounted on the second substrate can be further reduced.

  In addition, the present invention includes the electronic circuit device described above, in which an insulating sheet is disposed in the space.

  According to this configuration, the digital component is mounted on the first surface of the first substrate, the analog component is mounted on the fourth surface of the second substrate, and the second surface and the second surface of the first substrate are mounted. By providing an insulating sheet between the substrate and the third surface, the distance between the digital component and the analog component increases, so the influence of noise generated by the digital component on the analog component can be reduced. A simple electronic circuit device can be realized.

  In addition, the present invention includes the electronic circuit device described above, which is provided inside the insulating sheet and includes a built-in circuit component connected to the digital component.

  According to this configuration, by incorporating the circuit component, the interval between the digital components mounted on the first surface of the first substrate can be minimized, and the digital component and the built-in circuit component can be reduced. Wiring for connection can be embedded in the built-in part. Further, by reducing the distance between the digital components, the wiring length between the digital components can be shortened, and the signal loop that causes unnecessary radiation can be reduced. Therefore, unnecessary radiation can be reduced.

  The present invention is the above electronic circuit device, wherein the built-in circuit component is a resistor element, and at least two digital components mounted on the first surface of the first substrate are interposed via the resistor element. Including connected ones.

  According to this configuration, even if unnecessary radiation occurs due to mismatch between the characteristic impedance and resistance of the wiring, the resistance is a built-in circuit component. Can be trapped inside. Moreover, not only can the connection wiring between the digital components be built-in, but it can also be formed as an inner layer in the laminated substrate, facilitating wiring and reducing the wiring length.

  The present invention is the above electronic circuit device, wherein the first substrate is provided with a conductive path that penetrates the first substrate, and is mounted on the first surface of the first substrate. The digital component and the built-in circuit component include those connected via the conductive path.

  According to this configuration, since the conductive path connecting the digital component and the built-in circuit component is wired in a direction perpendicular to the first substrate and the second substrate, the line length can be reduced. Therefore, the generation of noise can be reduced. Even if noise is generated from the conductive path, the noise propagates in the inner layer of the substrate and is emitted, so that the influence of noise on the analog component can be reduced.

  Further, the present invention includes the electronic circuit device described above, wherein the fourth surface of the second substrate is provided with a connection portion that is electrically connected to another mounting substrate.

  Moreover, this invention is said electronic circuit apparatus, Comprising: The said 1st and 2nd board | substrate contains a thing thinner than the said insulating sheet.

  With this configuration, it is possible to reduce stress due to thermal expansion of the first and second substrates, and thus it is possible to suppress a decrease in bondability between the substrate and the insulating sheet.

  Further, the present invention includes the electronic circuit device, wherein the heat generating component among the analog components is disposed so as to avoid a position facing the digital component in a plane.

  With this configuration, the influence of heat transmitted through the substrate can be avoided.

  Further, the present invention includes the electronic circuit device described above, wherein a heat dissipation member that contacts the digital component is provided.

  According to this configuration, since the heat radiating member that comes into contact with the digital component is provided, the heat radiating member plays a role of forcibly releasing heat. For this reason, the heat generated from the digital component is efficiently radiated from the first surface of the first substrate, heat does not flow into the second substrate, and the influence of heat can be blocked.

  The present invention includes the electronic circuit device, wherein the digital component is an integrated circuit that performs at least one of modulation processing and demodulation processing of a multicarrier signal. Here, even an integrated circuit that performs both modulation and demodulation processing is effective.

  The present invention is the above electronic circuit device, wherein the multicarrier signal is a power line communication signal that can be transmitted to a power line having a pair of lines.

Further, the present invention is a power line communication device using the electronic circuit device, wherein the electronic circuit device and a power line communication signal output from the electronic circuit device are superimposed on an AC voltage transmitted through the power line, A coupler that separates a power line communication signal from an AC voltage transmitted to the power line and outputs the separated signal to the electronic circuit device is provided.

  According to this configuration, it is possible to provide a power line communication device that can perform high-speed communication and has low noise and high reliability.

  Moreover, this invention is the said electronic circuit apparatus, Comprising: The said insulating sheet contains an inorganic filler and a thermosetting resin.

  According to this configuration, it is possible to control the thermal expansion coefficient, dielectric constant, and thermal conductivity by selecting an inorganic filler, improving the connection reliability of the conductive path connecting the two laminated substrates, and heat dissipation Can be improved.

  Moreover, this invention is an said electronic circuit apparatus, Comprising: The weight% of the inorganic filler in the said insulating sheet contains what is 70 weight%-95 weight%.

  Further, the present invention is the above electronic circuit device, wherein the connection portion is provided in the vicinity of one end of the second substrate, and the heat generating component is provided at an edge portion substantially diagonal to the connection portion. Including those provided.

  According to this configuration, since the heat generating component is provided at a position far from the connector, the heat from the heat generating component can be dissipated before reaching the connector. Further, by disposing a heat sink on the first surface side of the first substrate, heat can be efficiently radiated.

  The present invention includes the electronic circuit device, wherein the heat dissipation member is connected to the digital component via an insulating elastic member.

  With this configuration, the height of the component mounted on the first surface of the substrate can be absorbed by this elastic member, and the adhesion can be increased, so that the thermal contact property can be improved and the heat dissipation can be further improved. .

  The present invention is the above electronic circuit device, wherein the connecting portion is provided in the vicinity of one end of the second substrate, and the heat generating component is provided in the vicinity of the other end of the second substrate. Including things.

  According to this configuration, since the heat generating component is provided at a position far from the connector, the heat from the heat generating component can be dissipated before reaching the connector.

  It should be noted that the integrated circuit constituting the digital component that is the subject of the present invention is not necessarily a modulation / demodulation circuit such as a main IC, and is applied to the mounting of an integrated circuit having a large number of ground terminals, such as an AFE / IC. Is possible.

With the above configuration, the digital component is mounted on the first surface, the balanced filter is mounted on the second surface facing the first surface, and the second surface faces the mounting substrate. Therefore, the balanced filter can avoid the influence of noise from the digital component, and can reduce noise.
In addition, the distance between the digital parts can be reduced to the maximum, and wiring for connecting the digital parts and the built-in circuit parts can be inserted into the built-in part. By reducing the distance between the digital parts, the wiring length between the digital parts can be shortened, and the signal loop that causes the unnecessary radiation can be reduced. Therefore, unnecessary radiation can be reduced.

  In addition, at least two terminals of the digital component mounted on the first surface are connected via a resistor as the built-in circuit component, and unnecessary radiation occurs due to mismatch between the characteristic impedance of the wiring and the resistor. Even so, since the resistor is a built-in circuit component, this wiring is also confined in the built-in portion, and unnecessary radiation can be confined in the substrate. Moreover, not only can the connection wiring between the digital components be built-in, but it can also be formed as an inner layer in the laminated substrate, facilitating wiring and reducing the wiring length.

  Further, the digital component mounted on the first surface and the built-in circuit component are connected via a conductive path provided in the through via, so that the conductive path becomes a wiring in a direction perpendicular to the substrate surface, Not only can the wiring length be reduced, but even if unnecessary radiation occurs, it is propagated through the inner layer and emitted, and the influence of unnecessary radiation on the electronic circuit device can be reduced.

  In addition, by making the first and second substrates thinner than the insulating sheet, the stress due to thermal expansion of the first and second substrates can be reduced, and the deterioration of the bondability between the substrate and the insulating sheet is suppressed. can do.

  In addition, a digital component that performs digital signal processing is mounted on the first surface of the first substrate, and the second surface of the second substrate that faces the second surface of the first substrate faces the second surface of the first substrate. 4 is mounted with an analog component that performs analog signal processing, and a digital component is provided by interposing a space between the second surface of the first substrate and the third surface of the second substrate. Since the distance between the analog components is increased, an electronic circuit board capable of reducing the influence of noise generated from the digital components received by the analog components can be realized.

  In addition, a digital component that performs digital signal processing is mounted on the first surface of the first substrate, and a fourth surface that faces the third surface of the second substrate that faces the second surface of the first substrate. An analog component that performs analog signal processing is mounted on the surface of the first substrate, and a space is interposed between the second surface of the first substrate and the third surface of the second substrate. Since the distance between the analog components is increased, it is possible to realize an electronic circuit device capable of reducing the influence of noise generated from the digital components received by the analog components.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(Embodiment 1)
In the first embodiment, a PLC modem 100 in which a PLC module used for high-speed power line communication (PLC, Power Line Communication) is housed in a housing 101 will be described as an electronic circuit device. Note that the PLC modem 100 is an example of a power line communication device, and the power line communication device may be an electric device with a built-in PLC modem.

  In the present embodiment, as shown in a perspective view in FIG. 1 and a schematic cross-sectional view in FIG. 2, the PLC circuit module 200 is formed by two electronic circuit boards mounted on a motherboard 110 via connectors 120 as connecting portions. It is composed. That is, an Ethernet PHY IC 230 for performing modulation / demodulation of a signal transmitted through an Ethernet (registered trademark) cable on the first surface 200a of two electronic circuit boards constituting the PLC circuit module 200 built in the PLC modem 100, a power line PLC 210 that modulates and demodulates PLC signals (multi-carrier signals) that transmit signals, AFE IC 220 that performs necessary signal processing (for example, digital-analog conversion, etc.) on PLC signals, etc. Digital parts are mounted, and analog parts that are heat generating parts such as a balanced filter (band-pass filter) 260 and an operational amplifier 252 are mounted on the second surface 200b, which is the surface facing the first surface 200a. It is characterized by this. In this PLC circuit module 200, the first laminated substrate 10 and the second laminated substrate 30 are laminated via the composite sheet 20. A heat radiating member 700 is provided on the back side of the digital component so as to cover the entire first surface 200a, which is the digital component mounting surface of the first multilayer substrate, via a heat conductive elastic member 701.

  That is, in the electronic circuit device of the present invention, a digital component including a modulation / demodulation integrated circuit that performs digital signal processing, a band-pass filter 260 that is a balanced filter that blocks a power line communication signal in a predetermined frequency band, The digital component is mounted on the second surface, and the substrate on which the balanced filter 260 and the connector 120 as the external connection portion are mounted on the second surface facing the first surface is provided. It is characterized by.

  A circuit module 200 is shown in FIGS. FIG. 3 is a cross-sectional view of the circuit module 200, FIG. 4 is an explanatory view showing a planar arrangement of digital components and operational amplifiers that are heat-generating components, and FIG. 5 is a diagram showing a component arrangement on each surface of the circuit module 200. 5A is a first surface 200a that is a digital component mounting surface, FIG. 5B is a second surface 200b that is a digital component mounting surface, and FIG. 5C is a plan view showing a built-in component. It is. That is, in the first embodiment, as shown in FIG. 5A, the first surface 200a that is a digital component mounting surface is an Ethernet PHY that is an integrated circuit that performs digital signal modulation / demodulation processing and other digital signal processing. The first laminated substrate 10 on which digital parts such as the IC 230, the PLC / IC 210, the AFE / IC 220, the memory (SDRAM) 240, the memory (flash ROM) 241 and the reset IC 270 are mounted is the composite sheet 20 as an insulating sheet. It is fixed to the second laminated substrate 30 via Of the two laminated substrates, each of the first to fourth metal layers 12-15 is laminated and fixed to the first laminated substrate 10 via an insulating layer 17. Reference numerals 11 and 16 denote wiring patterns constituting the wiring on the front and back surfaces of the laminated substrate. Although this wiring pattern is also formed in the same manner as the first to fourth metal layers, it is regarded as a connection pad here, and the closest layer is the first metal layer 12. In addition, each of the first to fourth metal layers 32-35 constituting the wiring pattern is laminated and fixed to the second laminated substrate 30 via an insulating layer 37. 31 and 36 are wiring patterns constituting the wiring on the front and back surfaces of the laminated substrate. This wiring pattern is also formed in the same manner as the first to fourth metal layers, but here it is assumed to be a connection pad. The second multilayer substrate 30 is also formed in the same manner as the first multilayer substrate 10, but as shown in FIGS. 4 and 5C, the second surface 200b of the second multilayer substrate 30 is formed on the second surface 200b. Heat generating components such as an interface connector (connector) 120, a balanced filter 260, and an operational amplifier 252 are mounted. In FIG. 5B, a logic IC 263 is an integrated circuit that controls the operation of the display unit 105 described later. The attenuator 261 reduces the PLC reception signal and absorbs the load fluctuation of the PLC reception signal.

  FIG. 5C shows electronic components built in the composite sheet 20, all of which are mounted on the first laminated substrate 10 side. In FIG. 5C, reference numeral 181 denotes a built-in component connected to the AFE / IC 220. Reference numeral 182 denotes a built-in component connected to the PLC / IC 210. Reference numeral 183 denotes a built-in component connected to the memory (SDRAM) 240. Reference numeral 184 denotes a built-in component connected to the memory 241 (flash ROM). Reference numeral 185 denotes a built-in component connected to the reset IC. Reference numeral 381 denotes a built-in component connected to the Ethernet PHY IC 230.

  Here, the connector 120 and the operational amplifier 252 are disposed in the vicinity of the end of the second surface 200b. In addition, the connector 120 and the operational amplifier 252 are disposed at positions along the diagonal line of the second surface 200b.

  In recent years, power line communication devices tend to be required to be further downsized. One means for reducing the size of the PLC modem 100 is to increase the mounting density of built-in components (boards, electronic components, etc.) in the housing 101. When the mounting density of the built-in components in the housing 101 is increased, the space formed between the circuit module 200 and the mother board 100 in FIG. When the space is narrowed, the heat radiation area of the space is naturally reduced, so that the heat radiation efficiency of the circuit module 200 is lowered. Accordingly, the heat released from the analog component mounted on the second surface 200b and the heat generated from the electronic component mounted on the motherboard 100 are not efficiently radiated from the space, so that the temperature of the circuit module 200 is increased. Easy to do.

  In addition, among the analog components mounted on the second surface 200b, it is desirable to dispose a component with a large calorific value (for example, the operational amplifier 252) in the vicinity of the end of the second surface 200b. When the operational amplifier 252 having a large calorific value is disposed in the vicinity of the end of the second surface, the operational amplifier 252 is exposed to the outside air having a low temperature, and thus can efficiently dissipate heat by thermal convection with the outside air. As described above, it is possible to suppress the temperature increase of the circuit module 200 by efficiently dissipating the analog component having a large calorific value by heat convection with the outside air. When the connector 120 is formed of a material having low heat resistance such as a resin, the connector 120 is formed near one end of the second surface 200b and the operational amplifier 252 is formed near the other end on the second surface 200b. It is desirable to arrange. By disposing the connector 120 and the operational amplifier 252 in this manner, the distance between the connector 120 and the operational amplifier 252 can be increased, and the influence of heat generated from the operational amplifier 252 received by the connector 120 can be reduced.

In the case where the connector 120 is formed of a material having low heat resistance such as resin, it is also effective to dispose the connector 120 and the operational amplifier 252 diagonally on the second surface 200b. By disposing the connector 120 and the operational amplifier 252 diagonally, the distance between the connector 120 and the operational amplifier 252 can be increased, and the influence of heat generated from the operational amplifier 252 received by the connector 120 can be reduced. . The arrangement of the connector 120 and the operational amplifier 252 is not limited to the diagonal line of the second surface 200b, and may be arranged on a straight line parallel to a straight line that intersects one side of the second surface 200b at an acute angle. In the case where the connector 120 is formed of a material having high heat resistance, it is also preferable that the connector 120 is disposed near the end portion and the operational amplifier 252 is disposed near the connector 120 on the second surface 200b. . This is because when the connector 120 is formed of a material having high heat resistance, the connector 120 can dissipate heat generated from the operational amplifier 252 conducted through the circuit module 200.

  Here, the connector 120 and the operational amplifier 252 are arranged so as to maintain a predetermined distance. The circuit configuration of the PLC circuit module 200 including the PLC / IC 210 will be described later.

  As described above, the PLC circuit module 200 accommodated in the PLC modem 100 includes the first and second laminated substrates as shown in FIGS. The electronic circuit board constituted by the first and second laminated substrates is balanced with the first laminated substrate 10 having the Ethernet PHY IC 230 mounted on the first surface 200a and the low-pass filter 251 which is a balanced filter on the surface. A second laminated substrate 30 on which a mold filter (bandpass filter) 260 is mounted and an AFE / IC 220 is mounted is fixedly laminated via an insulating sheet 20. The first multilayer substrate 10 includes wiring layers 11 and 16 including pads on the front and back sides and metal layers 12, 13, 14, and 15 stacked via an insulating layer 17. The first metal layer 12 as the ground layer is disposed at the position closest to the Ethernet PHY • IC 230 on the back side among the four metal layers, and the pad B of the wiring pattern 11 is connected to the pad B via the via hole H1. And connected to the PLC IC 210.

  As described above, the first and second laminated substrates 10 and 30 are used as the electronic circuit substrates constituting the PLC circuit module 200. That is, the first laminated substrate 10 on which the PLC / IC 210 that is an integrated circuit configured to perform modulation / demodulation of the multicarrier signal is fixed to the second laminated substrate 30 via the composite sheet 20 as an insulating sheet. Has been. Each of the plurality of metal layers 32 to 35 that are stacked is stacked and fixed to the second stacked substrate 30 via the insulating layer 35. Also in the second laminated substrate 30, metal layers 31 and 36 constituting connection pads are formed on the front and back surfaces (see FIG. 3).

  In this configuration, the digital component is mounted on the first surface, the balanced filter is mounted on the second surface facing the first surface, and the second surface faces the mounting substrate. Therefore, the balanced filter can avoid the influence of noise from the digital component, can reduce noise, and can provide a highly reliable electronic circuit. The electromagnetic field distribution will be described later.

  Further, in the circuit module 200 described above, the Ethernet PHY / IC 230, the PLC / IC 210, and the AFE, which are integrated circuits for performing digital signal modulation / demodulation processing and other digital signal processing on the first surface 200a of the first laminated substrate 10, are provided. Digital components such as the IC 220, the memory 240, and the reset IC 270 are mounted, and the balanced filter 260 that performs analog signal processing, the operational amplifier 252 and the like are mounted on the second surface 200b of the second multilayer substrate 30. Therefore, analog parts and digital parts are not mixed on the first surface 200a and the second surface 200b, and the analog parts are mounted separately from the digital parts. Further, since the first laminated substrate 10 and the second laminated substrate 30 are laminated via the composite sheet 20, the distance separating the analog component and the digital component is increased by the thickness of the composite sheet 20. . The intensity of noise generated from a digital component decreases as the distance from the digital component that is a noise source decreases. Therefore, in the circuit module 200, the analog component is further separated from the digital component by the thickness of the composite sheet 20, so that the influence of noise generated from the digital component received by the analog component is reduced.

In FIG. 3, the circuit module 200 is provided with a via hole H2 penetrating the first laminated substrate 10, and the PLC IC 210 and the built-in electronic component 182 (for example, a resistance element) are electrically connected via the via hole H2. It is connected to the.
According to this configuration, even if impedance mismatch occurs between the characteristic impedance of the conductive path provided in the via hole H2 and the built-in electronic component, and even if unnecessary radiation is generated from the built-in electronic component and the conductive path, the built-in electronic component 182 and the conductive path are confined in the circuit module 200, and the unnecessary radiation can be shielded by the conductor layers 11 to 16 and 31 to 36 in the circuit module 200. Therefore, it is possible to reduce unnecessary radiation that affects the operation of the analog component mounted on the second surface 200b.

  Further, the distance between the bonding pad (not shown) which is the ground terminal of the PLC / IC 210 and the first metal layer 12 constituting the ground layer is the shortest, and without forming a via penetrating the laminated substrate, The ground terminal and the ground layer can be connected by the shallow inner via H1 penetrating only the insulating layer 17, and the ground terminal and the ground layer can be connected while maintaining processing accuracy. As a result, even when the number of pins of the ground terminal is large, the mounting area of the back surface of the multilayer substrate, that is, the surface on which the integrated circuit is not mounted is not reduced by the through via. Further, an increase in inductance due to an increase in the distance in the thickness direction of the multilayer substrate can be suppressed to a minimum.

  Here, the first metal layer 12 constituting the ground layer of the first laminated substrate 10 is formed by patterning a copper foil so as to have an occupied area of 80% or more of the substrate surface. In addition, on the upper layer side of the first metal layer 12 (side away from the modulation / demodulation IC (PLC / IC) 210), a second power source layer formed by similarly patterning a copper foil is formed. A metal layer 13 is formed. The second metal layer 13 is connected to a power supply terminal (not shown) of the PLC / IC 210, the memory 240, and the like through an inner via.

  The first and second laminated substrates 10 and 30 include insulating layers 17 and 37 and metal layers 12 and 13 that form patterns such as a ground layer, a power supply layer, and a wiring layer between the insulating layers 17 and 37. 14, 15, 32, 33, 34, 35 are sandwiched and wiring patterns 11, 16, 31, 36 constituting connection pads are arranged on the front and back surfaces, and these are electrically connected by via holes formed in the insulating layer 17. Configured to connect to. The via hole can be formed by, for example, laser processing, drilling, or die processing. Laser processing is preferable because the through holes can be formed with a fine pitch and no shavings are generated. In laser processing, if a carbon dioxide laser or excimer laser is used, processing is easy. As an electrical connection method, it may be formed by electroless plating or may be formed by filling a conductive substance.

  In addition, the metal layers 11, 12, 13, 14, 15, 16 (31, 32, 33, 34, 35, 36) constituting the wiring pattern, the ground layer, and the power supply layer are made of copper foil, but are conductive. Any material having electrical conductivity such as a conductive resin composition may be used. For example, when a copper foil is used as the wiring pattern, for example, a copper foil having a thickness of about 12 μm to 35 μm manufactured by electrolytic plating is applicable. In order for copper foil to improve adhesiveness with insulating layers 17 and 37, it is desirable to roughen the surface which contacts insulating layers 17 and 37. Further, as the copper foil, a copper foil surface that has been subjected to a coupling treatment or a copper foil surface that is plated with tin, zinc, or nickel can be used in order to improve adhesion and oxidation resistance. As the metal layer, a metal plate lead frame formed by an etching method or a punching method may be used. In the case of using a lead frame, a green sheet is divided and formed on a unit by a printing method on the lead frame and fixed, and then component mounting is performed as necessary, and an insulating layer of the next layer is laminated, Further, it can be easily formed by sequentially stacking and laminating the metal layers of the next layer, etc., and finally dividing the laminated substrate constituting the unit here.

The composite sheet as the insulating sheet 20 for fixing the first and second laminated substrates 10 and 30 of the present invention is composed of a mixture containing an inorganic filler and a thermosetting resin, and is called a so-called green sheet. In an uncured state, it is laminated with circuit components and conductive paths drilled as needed, and is laminated with circuit components and conductive paths built in by drying and curing at about 200 ° C. The Holes for circuit components and conductive paths can be formed by, for example, laser processing, drilling, or die processing. Laser processing is preferable because the through holes can be formed with a fine pitch and no shavings are generated. In laser processing, if a carbon dioxide laser or excimer laser is used, processing is easy. In addition, you may form simultaneously when shape | molding a mixture and forming a green sheet. As the inorganic filler, for example, Al ₂ O ₃ , MgO, BN, AlN, or SiO ₂ can be used. The inorganic filler is preferably 70% to 95% by weight based on the mixture. The average particle size of the inorganic filler is preferably 0.1 μm to 100 μm. For the thermosetting resin, for example, epoxy resin, phenol resin or cyanate resin having high heat resistance is preferable. Epoxy resins are particularly preferred because of their particularly high heat resistance. The mixture may further contain a dispersant, a colorant, a coupling agent, or a release agent.

  In addition, since a mixture of an inorganic filler and a thermosetting resin is used as the material of the insulating sheet 20, unlike a ceramic substrate, it is not necessary to fire at a high temperature and is formed by drying at about 200 ° C. Easy to manufacture.

  Moreover, by selecting the inorganic filler used for the insulating sheet 20, the linear expansion coefficient, thermal conductivity, dielectric constant, etc. of the insulating sheet 20 can be easily controlled. When the linear expansion coefficient of the insulating sheet 20 is substantially equal to that of the semiconductor element, it is possible to prevent the occurrence of cracks and the like due to temperature changes and to configure a highly reliable electronic circuit board. When the thermal conductivity of the insulating sheet 20 is improved, a highly reliable electronic circuit board can be obtained even when circuit components are mounted at a high density.

  The plate-shaped insulating sheet 20 may be heat-treated at a temperature lower than the curing temperature of the thermosetting resin. By performing the heat treatment, the adhesiveness can be removed while maintaining the flexibility of the insulating sheet 20, so that the subsequent processing becomes easy. In addition, in a mixture in which a thermosetting resin is dissolved with a solvent, a part of the solvent can be removed by heat treatment.

  The conductive path P formed in the insulating sheet 20 is made of, for example, a thermosetting conductive material. As the thermosetting conductive substance, for example, a conductive resin composition in which metal particles and a thermosetting resin are mixed can be used. As the metal particles, gold, silver, copper, nickel or the like can be used. Gold, silver, copper, or nickel is preferable as a conductive material because of its high conductivity, and copper is particularly preferable because of its high conductivity and low migration. As the thermosetting resin, for example, an epoxy resin, a phenol resin, or a cyanate resin can be used. Epoxy resins are particularly suitable because of their high heat resistance.

  Here, the circuit component 18 incorporated in the insulating sheet 20 may be either an active component or a passive component. For example, a semiconductor element such as a transistor, IC, or LSI is used as the active component. The semiconductor element may be a semiconductor bare chip or a semiconductor element sealed with resin. As the passive component, a chip resistor, a chip capacitor, a chip inductor, or the like is used. In addition, as the circuit component, one that does not include a passive component is also applicable.

  Moreover, since the built-in circuit component 18 can be shielded from the outside air by using the insulating sheet 20, it is possible to prevent a decrease in reliability due to humidity.

  Hereinafter, a PLC modem in which the first multilayer substrate (and the second multilayer substrate) as the electronic circuit substrate is used in a module for high-speed power line communication (PLC) will be described in detail. FIG. 6 is an external perspective view showing the front surface of the PLC modem.

  The PLC modem includes a housing 101, and a display unit 105 including LEDs (Light Emitting Diodes) 105A, 105B, and 105C is provided on the front surface of the housing 101. Further, on the rear surface of the housing 101, a power connector, a modular jack (not shown) for LAN (Local Area Network) such as RJ45, and a changeover switch 106 for switching operation modes and the like are provided. A power cable (not shown in FIG. 1) is connected to the power connector, and a LAN cable (not shown in FIG. 1) is connected to the modular jack. The PLC modem may be further provided with a Dsub (D-subminiature) connector to connect a Dsub cable. Needless to say, other known connectors may be provided. In addition, as a display part, you may change a color with one LED other than several LED, and may display a communication speed etc. on a liquid crystal, an EL display, etc. FIG. Further, FIG. 5 shows a configuration example of a PLC modem as a power line communication device, but the present invention can also be applied to an electric device (for example, a home appliance such as a television) provided with a PLC modem.

  FIG. 7 is an explanatory view showing the inside of the casing of the PLC modem. In this PLC modem, a PLC module 200 is mounted on a mother board 110 via a connector 120 in a casing 101, and a heat radiating plate 700 is mounted on the upper surface of the PLC module via an elastic body 702 made of heat conductive rubber. It is brought into contact with the inner wall of the body 101. Here, reference numeral 103 denotes an RJ45 connector (Ethernet connector), which is connected to the net through this connector. Reference numeral 701 denotes a cover, reference numeral 703 denotes a power supply unit, and reference numeral 704 denotes a power supply connector.

  FIG. 8 is a block diagram showing the configuration of this PLC modem. The PLC circuit module 200 includes a main IC (Integrated Circuit) 210, an AFE IC (Analog Front End IC) 220, a memory 240, a low-pass filter 251, an operational amplifier 252, and a balanced filter 260 as a modulation / demodulation IC (PLC / IC). Is provided. The switching power supply 300 and the coupler 270 are connected to the power connector 102 and further connected to the power line 900 via the power cable 600, the power plug 400, and the outlet 500.

  The PLC / IC 210 includes a CPU (Central Processing Unit) 211, a PLC / MAC (Power Line Communication / Media Access Control layer) block 212, and a PLC / PHY (Power Line Communication / Physic layer) block 213. The CPU 211 is equipped with a 32-bit RISC (Reduced Instruction Set Computer) processor. The PLC / MAC block 212 manages the MAC layer of transmission / reception signals, and the PLC / PHY block 213 manages the PHY layer of transmission / reception signals. The AFE / IC 220 includes a DA converter (DAC) 221, an AD converter (ADC) 222, and a variable amplifier (VGA) 223. The coupler 270 includes a coil transformer 271 and coupling capacitors 272a and 272b. The CPU 211 uses the data stored in the memory 240 to control the operation of the PLC / MAC block 212 and the PLC / PHY block 213, and also controls the entire PLC modem 100.

  The PLC modem 100 performs transmission using a plurality of subcarriers such as the OFDM method, and digital signal processing for performing such transmission is performed by the PLC / IC 210, particularly the PLC / PHY block 213.

  FIG. 9 is a schematic functional block diagram of an example of a digital signal processing unit realized by the PLC / IC 210, which is used when performing OFDM transmission using wavelet transform. 9 includes a control unit 2110, a symbol mapper 2111, a serial-parallel converter (S / P converter) 2112, an inverse wavelet converter 2113, a wavelet converter 2114, a parallel-serial converter (P / P). S converter) 2115 and demapper 2116.

  The symbol mapper 2111 converts bit data to be transmitted into symbol data and performs symbol mapping (for example, PAM modulation) according to each symbol data. The S / P converter 2112 converts the mapped serial data into parallel data. The inverse wavelet transformer 2113 performs inverse wavelet transform on parallel data to generate data on the time axis, and generates a sample value series representing a transmission symbol. This data is sent to the DA converter (DAC) 221 of the AFE / IC 220.

  The wavelet transformer 2114 performs discrete wavelet transform on the frequency axis of received digital data (sample value series sampled at the same sample rate as that at the time of transmission) obtained from the AD converter (ADC) 222 of the AFE / IC 220. is there. The P / S converter 2115 converts parallel data on the frequency axis into serial data. The demapper 2116 calculates the amplitude value of each subcarrier, determines the received signal, and obtains received data.

  Communication by the PLC modem 100 is generally performed as follows. When data input from the RJ45 connector 103 is received, the digital transmission signal that is sent to the PLC / IC 210 via the Ethernet PHY / IC 230 and subjected to digital signal processing is converted into a DA converter (DAC) of the AFE / IC 220. ) 221 is converted into an analog signal and output to the power line 900 via the low-pass filter 251, the operational amplifier (driver IC) 252, the coupler 270, the power connector 102, the power cable 600, the power plug 400, and the outlet 500.

  When receiving a signal from the power line 900, the signal is sent to the band-pass filter 260, which is a balanced filter, via the coupler 270, and after the gain is adjusted by the variable amplifier (VGA) 223 of the AFE / IC 220, the AD converter ( ADC) 222 is converted into a digital signal, and then sent to PLC / IC 210, where it is converted into digital data by performing digital signal processing. Then, the data is output from the RJ45 connector 103 via the Ethernet PHY IC 230.

  Here, the low-pass filter 251 disposed on the transmission side is composed of a large number of capacitors and coils, as shown in an equivalent circuit diagram of FIG. 10 (a) or (b). The band-pass filter 260 arranged on the receiving side is also composed of a large number of capacitors and coils as shown in the equivalent circuit diagram of FIG.

  A low-pass filter 251a shown in FIG. 10A has two capacitors 251a1 and 251a2 connected between a pair of lines 601 and 602. CL parallel circuits 251a3 and 251a4 are connected in series to each of the pair of lines 601 and 602 so as to be sandwiched between two capacitors 251a1 and 251a2. Further, the low pass filter 251b shown in FIG. 10B has one capacitor 251b1 connected between the pair of lines 601 and 602. Two inductors 251b2 and 251b3 are connected in series to the line 601 so as to sandwich the capacitor 251b1. Two inductors 251b4 and 251b5 are connected in series to the line 602 so as to sandwich the capacitor 251b1.

  The line 601 and the line 602 are connected to a power line 900 having a pair of lines via a power cable 600 shown in FIG. In the low-pass filter 251a shown in FIG. 10A, when the CL parallel circuits 251a3 and 251a4 have the same circuit constant, the impedance viewed from each of the pair of lines included in the power line 900 is the same. Accordingly, the low-pass filter 251a constitutes a balanced filter. 10B, when the circuit constants of the inductors 251b2 and 251b3 and the inductors 251b4 and 251b5 are the same, the impedance viewed from each of the pair of lines included in the power line 900 is the same. is there. Therefore, this low-pass filter 251b constitutes a balanced filter, similar to the low-pass filter 251a. By doing so, the power line can be balanced between a pair of lines, so that the noise transmitted through one line can be offset by the noise transmitted through the other line, and the noise can be suppressed. I can do it.

  The band pass filter 260 shown in FIG. 10C includes the low pass filter 251a shown in FIG. 10A and the high pass filter 251c connected in series to the lines 601 and 602. The high pass filter 251c has one inductor 251c1 connected between the pair of lines 601 and 602. Two capacitors 251c2 and 251c3 are connected in series to the line 601 so as to sandwich the inductor 251c. Two capacitors 251c4 and 251c5 are connected in series to the line 602 so as to sandwich the inductor 251c1.

  In the band-pass filter 260 shown in FIG. 10C, when the circuit constants of the capacitors 251c2 and 251c3 and the capacitors 251c4 and 251c5 are the same, the impedance viewed from each of the pair of lines included in the power line 900 is the same. . Therefore, the band pass filter 260 constitutes a balanced filter. By doing so, it is possible to balance between a pair of lines that the power line has, and balance between the pair of lines that the power line has, so that the noise transmitted through one line can be transmitted through the other line. Noise can be offset and noise can be suppressed.

  The filters shown in FIG. 10 are shown when the impedance viewed from each of the pair of lines included in the power line 900 is the same, but these impedances do not have to be completely the same, and the effect of suppressing noise. It suffices if they are substantially the same. For example, if the impedance difference seen from each line is ± 5%, the effect of noise suppression can be achieved.

  As described above, the PLC circuit module 200 is formed by laminating the first laminated substrate 10 and the second laminated substrate 30 via the composite sheet 20, of which the first laminated substrate 10 is As shown in FIG. 11, a relatively small part is mounted on the front surface side including four metal layers 11, 12, 13, and 14 as inner layers, and a PLC / IC 210, a memory 240, etc. are mounted on the back side. It is equipped. Further, as shown in FIG. 11, the second laminated substrate 30 includes four metal layers 31, 32, 33, and 34 as inner layers, and a relatively small component is mounted on the back side, The balanced filters 251 and 260 and the AFEIC 220 are mounted on the surface side.

Next, a method for manufacturing the PLC circuit module 200 will be described.
12A to 12F are perspective views showing an embodiment of a manufacturing process of a PLC module. The cross-sectional views of FIG. 12 are shown in FIGS. FIGS. 14A to 14F are cross-sectional views showing a manufacturing process of a first laminated substrate as an electronic circuit substrate constituting this PLC module.
First, prior to the description of the manufacturing process of the PLC module, the manufacturing process of the first laminated substrate will be described.

  First, as shown in FIG. 14A, an uncured insulating layer 17 in which a glass woven fabric is impregnated with a thermosetting resin is formed, and copper as metal layers 11 and 12 is formed on both surfaces of the insulating layer 17. Prepare a piece of foil. In the same manner, those in which copper foils as metal layers 13 and 14 are attached to both surfaces of the insulating layer 17 and those in which copper foils as metal layers 15 and 16 are attached to both surfaces of the insulating layer 17 are prepared. The resin of the insulating layer is cured by applying pressure while applying heat to the double-sided substrate. An aramid nonwoven fabric or an inorganic filler may be used as the material for the insulating layer. An epoxy resin is used as the thermosetting resin, but a phenol resin or the like may be used.

Thereafter, as shown in FIG. 14B, each metal layer is patterned by photolithography to form a wiring pattern. Then, as shown in FIG.14 (c), it presses, heating while pinching the insulating layer 17P called a prepreg. A plate-like body is formed by pressurizing the aligned and overlapped layers, and then heated to cure the thermosetting resin in the insulating layers 17 and 17P, and the six metal layers 11, 12 are cured. , 13, 14, 15 and 16 are formed. Heating is performed at a temperature equal to or higher than the temperature at which the thermosetting resin in the insulating layers 17 and 17P is cured (for example, 150 ° C. to 260 ° C.), and the uncured insulating layer becomes the insulating layer 17. At the time of curing the thermosetting resin of the insulating layer in the uncured state by heating, by pressing at a pressure of 10kg / cm ² ~200kg / cm ² while heating, the mechanical strength of the circuit component module Can be improved.

  Thereafter, as shown in FIG. 14D, a hole H up to the ground layer 15 is formed using a laser. As described above, the hole H can be formed by laser processing, drilling, or die processing.

Thereafter, as shown in FIG. 14E, a through hole H penetrating the laminated substrate 10 is formed.
Further, as shown in FIG. 14 (f), plating is performed in the through hole H, and electrical connection is made to the metal layer 16 and the ground layer 15 to be a pad. Here, the conductive resin composition may be filled. In this way, the first laminated substrate is formed.

  In this embodiment, the wiring patterns 11 and 16 which are the outermost layers are also patterned and then stacked, and finally the through hole H is formed and plating is performed in the through hole. The hole and the wiring pattern 11 can be connected by performing selective plating again to form a plating layer over the wiring pattern 16 serving as a pad from the inside of the through hole. Moreover, it is also possible to form a pad on the through hole if the outermost layer is finally attached with a copper foil and patterned.

  Similarly, the second laminated substrate 30 is formed. Although the circuit components to be mounted are different, the second laminated substrate is formed through the same process as the first laminated substrate for manufacturing.

  Next, when mounting the PLC module, first, as shown in FIGS. 12A and 13A, the circuit component 18 is mounted on the upper surface of the first multilayer substrate 10.

  Next, as shown in FIGS. 12B and 13B, a second laminated substrate 30 is prepared.

  Thereafter, as shown in FIG. 12C and FIG. 13C, the composite sheet 20 is formed, and the through holes H for forming parts and forming vias (conductive paths) are formed. The composite sheet 20 forms a plate-shaped composite sheet by molding a mixture containing an inorganic filler and a thermosetting resin. The plate-shaped composite sheet 20 is obtained by mixing an inorganic filler and an uncured thermosetting resin to obtain a paste-like kneaded product, and molding the paste-like kneaded product to a constant thickness. And the plate-shaped body in which the through-hole H was formed is formed by forming the through-hole H for via | veer formation (conductive path) in the desired position of the plate-shaped composite sheet 20. The through hole H can be formed by, for example, laser processing, drilling, or die processing. Here, the through hole H may be formed at the same time when the paste-like kneaded product is formed to form the plate-shaped composite sheet 20.

  And as shown in FIG.12 (d) and FIG.13 (d), the conductive path P is formed by filling the through-hole H of a composite sheet with a conductive resin composition.

Then, as shown in FIG. 12 (e) and FIG. 13 (e), the circuit board 18 is formed by aligning the first substrate and the second substrate via the composite sheet 20 and pressurizing the stacked ones. After the plate-like body embedded with is formed, the thermosetting resin in the insulating sheet 20 and the conductive resin composition is cured by heating the plate-like body, and the first laminated substrate 10 and the second laminated substrate are cured. A laminated body in which the circuit components 18 are embedded between 30 is formed. Heating is performed at a temperature (for example, 150 ° C. to 260 ° C.) equal to or higher than the temperature at which the thermosetting resin in the composite sheet 20 and the conductive resin composition is cured, and the uncured composite sheet 20 is cured. Incidentally, when curing the composite sheet of uncured by heating, by pressing at a pressure of 10kg / cm ² ~200kg / cm ² while heating, it is possible to improve the mechanical strength of the PLC circuit module.

  Thereafter, as shown in FIG. 12 (f), the PLC / IC 210 and the memory 240 are mounted on the lower surface of the first multilayer substrate 10, and the AFEIC 220 and the balanced filters 251 and 260 are mounted on the upper surface of the second multilayer substrate 30. And the PLC module of the present embodiment is completed.

  The PLC module formed in this way is housed in the casings 101a and 101b as shown in FIG. 6 to complete the PLC modem as shown in FIG.

  Thus, according to the PLC module of the present embodiment, the digital component is mounted on the first surface 200a, and the analog component and the connecting portion are mounted on the second surface 200b opposite to the first surface 200a. Since the second surface faces the mounting substrate, heat from the digital component is efficiently radiated from the first surface of the substrate, and the second surface side is the second surface side. It is possible to prevent heat from being accumulated in the electronic circuit board.

In addition, since the operational amplifier 252 that is an analog component that generates a large amount of heat is disposed at a position farthest from the connector 120 that is a connection portion, it is efficient to prevent a temperature rise.
Furthermore, since the back side of the digital component mounted on the first surface is brought into contact with the heat radiating member via an elastic member that is electrically insulating and has good thermal conductivity, the heat radiating member generates heat. It will play the role of forced release. For this reason, heat generated from the digital component is efficiently radiated from the entire surface from the first surface of the substrate, and heat does not flow into the second surface, so that the influence of heat can be blocked.
In addition, since the modulation / demodulation IC and the balanced filter are configured not to be arranged on the same surface of the multilayer substrate, it is possible to reduce the influence of noise, and to provide a small, low-cost module with good characteristics. Obtainable.

Hereinafter, specific examples of the present invention will be described.
An example of the manufacturing method of the electronic circuit board which comprises the PLC module of this invention is demonstrated.

  In producing the composite sheet plate, first, a predetermined amount of a paste-like mixture mixed with a desired composition is dropped onto a release film. The pasty mixture was prepared by mixing an inorganic filler and a liquid thermosetting resin for about 10 minutes with a stirring mixer. The stirring mixer used is one in which an inorganic filler and a liquid thermosetting resin are put into a container of a predetermined capacity and revolved while rotating the container itself. Even if the viscosity of the mixture is relatively high, sufficient dispersion is achieved. A state is obtained. A 75 μm thick polyethylene terephthalate film was used as the release film, and the film surface was subjected to release treatment with silicon.

  Next, the release film was further stacked on the paste-like mixture on the release film, and pressed to a thickness of 500 μm with a pressure press to obtain a plate-like mixture. Next, the plate-like mixture sandwiched between the release films was heated together with the release film, and heat-treated under conditions where the stickiness of the plate-like mixture disappeared. The heat treatment is held at a temperature of 120 ° C. for 15 minutes. By this heat treatment, the adhesiveness of the plate-like mixture is lost, so that the release film can be easily peeled off. Since the liquid epoxy resin used in this example has a curing temperature of 130 ° C., it is in an uncured state (B stage) under this heat treatment condition.

Next, the release film is peeled off from the plate-like mixture, and the plate-like mixture is sandwiched between heat-resistant release films (PPS: polyphenylene sulfite, thickness 75 μm) and pressed with a pressure of 50 kg / cm ^2. The plate-like mixture was cured by heating at a temperature of 170 ° C.

  Next, an insulating layer was obtained by peeling the heat-resistant release film from the cured plate-like mixture. This insulating layer was processed into predetermined dimensions, and thermal conductivity, linear expansion coefficient, and the like were measured. The thermal conductivity was obtained by calculation from the temperature rise on the opposite surface, with the surface of the sample cut into 10 mm squares heated by contacting with a heater. The linear expansion coefficient was obtained from an average value of the dimensional changes by measuring the dimensional change of the insulating layer when the temperature was raised from room temperature to 140 ° C. With respect to the withstand voltage, the withstand voltage when an AC voltage was applied in the thickness direction of the insulating layer was obtained, and the withstand voltage per unit thickness was calculated. Here, the insulating layer refers to a substrate that is electrically insulated.

When Al ₂ O ₃ is used as the inorganic filler, the insulating layer produced by the above method is compared with a conventional glass-epoxy substrate (thermal conductivity 0.2 w / mK to 0.3 w / mK). The thermal conductivity was about 10 times or more. By making the amount of Al ₂ O ₃ 85% by weight or more, the thermal conductivity could be made 2.8 w / mK or more. Al ₂ O ₃ has the advantage of low cost.

Further, when AlN or MgO was used as the inorganic filler, a thermal conductivity equal to or higher than that when Al ₂ O ₃ was used was obtained. When amorphous SiO ₂ was used as the inorganic filler, the linear expansion coefficient was closer to that of the silicon semiconductor (linear expansion coefficient 3 × 10 ⁻⁶ / ° C.). Therefore, an insulating layer using amorphous SiO ₂ as an inorganic filler is suitable as a flip chip substrate on which a semiconductor is directly mounted.

In addition, when SiO ₂ was used as the inorganic filler, an insulating layer having a low dielectric constant was obtained. SiO ₂ also has an advantage of low specific gravity.

In addition, when BN was used as the inorganic filler, an insulating layer having a high thermal conductivity and a low linear expansion coefficient was obtained. Except for the case where 60% by weight of Al ₂ O ₃ was used as the inorganic filler, the withstand voltage of the insulating layer was 10 kV / mm or more. The withstand voltage of the insulating layer is an index of adhesiveness between the inorganic filler that is the material of the insulating layer and the thermosetting resin. That is, when the adhesiveness between the inorganic filler and the thermosetting resin is poor, a minute gap is generated between them and the dielectric strength voltage is lowered. Such a minute gap causes a reduction in the reliability of the circuit component built-in module. In general, if the withstand voltage is 10 kV / mm or more, it can be determined that the adhesion between the inorganic filler and the thermosetting resin is good. Therefore, the amount of the inorganic filler is preferably 70% by weight or more.

  In addition, since the intensity | strength of an insulating layer will fall when content of a thermosetting resin is low, it is preferable that a thermosetting resin is 4.8 weight% or more.

In this example, an epoxy resin (WE-2025, including acid anhydride curing agent) manufactured by Nippon Pernox Co., Ltd. was used as the liquid epoxy resin. As the phenol resin, a phenol resin (Phenolite, VH4150) manufactured by Dainippon Ink Co., Ltd. was used. As the cyanate resin, a cyanate resin (AroCy, M-30) manufactured by Asahi Ciba Co., Ltd. was used. In this example, carbon black or a dispersant was added as an additive.
Using this composite sheet, the substrate used in the electronic circuit of the present invention can be obtained by sandwiching between the first laminated substrate 10 and the second laminated substrate 30 and heating with pressure.
A connector is attached to this, and the semiconductor device can be obtained by being attached to the mother board and being attached to the housing 101 via a heat conductive rubber and a heat radiating plate.
Needless to say, Example 1 can also be applied to the following embodiments.

  FIG. 17 shows the result of measuring the electromagnetic field distribution of this module. FIGS. 17A and 17B show the results of measuring the electric field peak value at 61.3 MHz for MS230, which is a conventional large substrate, and MS250, which is the substrate of this example. FIGS. 17C and 17D show the results of measuring the electric field peak value at 125 MHz for MS230 and MS250. A region with a high contour line density indicates a region with a large change in electric field strength. At this time, the electric field peak value at the time of transmission was 104.25 dBuV at MS230 at 61.3 MHz, whereas it was 98.92 dBuV at MS250. It can be seen that the value of 5.53BuV is lower in the case of <BR> W>. In addition, at 125 MHz, MS230 was 96.47 dBuV, while MS250 was 90.33 dBuV. At this time, the difference in the electric field peak value at the time of transmission is 6.14 BuV lower in the case of the module of the present invention. You can see that Further, the frequency range higher than this was also measured, but it was almost the same between MS230 and MS250.

FIG. 18 shows a state of unnecessary radiation emitted from the conductive path provided in the through via H2.
A digital signal processed by the PLC / IC 210 flows through the conductive path, and unnecessary radiation is emitted in a direction perpendicular to the conductive path formed by the through via H2. Unwanted radiation emitted from the conductive path is generated in a direction perpendicular to the substrate surface of these laminated substrates as indicated by arrows in the drawing, and is caused by the conductor layers 11 to 16 and 31 to 36 in the circuit module 200. Since it is shielded, the intensity of unnecessary radiation emitted to the outside of the circuit module 200 is smaller than the intensity of unnecessary radiation generated in the conductive path.
As described above, since the conductive path is provided in a direction perpendicular to the second surface 200b on which the analog component is mounted, the direction in which unnecessary radiation generated in the conductive path propagates as shown by the arrow is the second direction. It becomes parallel to the surface 200b. Therefore, since unnecessary radiation does not propagate toward the second surface 200b, it is possible to suppress the influence of unnecessary radiation received by the analog component.
18, the built-in electronic component refers to the built-in electronic component 182 in FIG. 3 and the circuit component 18 in FIG. 12, and the analog component refers to the balanced type 260 and the operational amplifier 252 in FIG.

(Embodiment 2)
Next, a second embodiment of the present invention will be described.
In the first embodiment, when the module is housed in the casing 101, the heat radiating plate is attached through rubber as an elastic body having good thermal conductivity. However, as shown in FIG. You may make it accommodate in the housing | casing 101 as it is, without passing through a board.

(Embodiment 3)
Next, a third embodiment of the present invention will be described.
In the present embodiment, as shown in FIG. 16, metal plates 40 and 41 for heat dissipation are laminated on the upper and lower surfaces of the PLC module obtained in the first embodiment via composite sheets 42 and 43, respectively. By configuring, the heat dissipation as a module is effectively performed. Others are formed in the same manner as the PLC module of the first embodiment shown in FIG. The same symbols are assigned to the same parts. Here, the connector 120 as a connection portion appears when cut by another cross section, but is not shown because it does not exist in this cross section.

  According to this configuration, even when the degree of circuit integration is increased, the heat dissipation area can be increased by simultaneously configuring the heat dissipation plates on the upper and lower surfaces, and a small and low-cost module can be configured.

  In addition, although the case where two metal plates for heat dissipation were demonstrated was demonstrated, the metal plate may be one. For example, a heat radiation area can be expanded by providing a metal plate only on an integrated circuit (for example, main IC) that generates the largest amount of heat via a composite sheet.

(Embodiment 4)
Next, a fourth embodiment of the present invention will be described. In the present embodiment, as schematically shown in FIG. 19, the first and second multilayer substrates 10 and 30 are thinner than the composite sheet 20 as an insulating sheet interposed between them. .
With this configuration, it is possible to reduce stress due to thermal expansion of the first and second substrates, and thus it is possible to suppress a decrease in bondability between the substrate and the insulating sheet.
Conventionally, as shown in FIG. 20, the number of layers of the multilayer substrates 1010 and 1030 is often determined by the amount of wiring of the circuit. Therefore, when the amount of wiring is large, the number of layers of the multilayer substrate increases and the thickness is Become thicker. Further, as the substrate becomes thicker, the warping stress due to the difference in thermal expansion coefficient increases, and there is a problem that the bonding reliability of the composite sheet 1020 and the conductive paste for bonding decreases. For example, by making the first and second laminated substrates 10 and 30 thinner than the composite sheet 20, the stress due to the thermal expansion of the substrate is reduced, and the bonding reliability between the substrate and the composite sheet, that is, the through via is improved. be able to.

(Embodiment 5)
Next, a fifth embodiment of the present invention will be described. In this embodiment, as schematically shown in FIG. 21, the resistor connected between the ICs 215 and 216 mounted on the first multilayer substrate 10 is the built-in circuit component 214 and is connected via vias. is there.
For comparison, FIG. 22 shows a case where a resistor 1214 is arranged on the first laminated substrate 1010 and connected between the ICs 1215 and 1216.
From the comparison between FIG. 21 and FIG. 22, according to this configuration, not only can the interval between the ICs 215 and 216 be reduced by incorporating the resistor 214, but also the wiring for connection can be incorporated, and therefore unnecessary radiation due to impedance mismatching. Can be confined in the substrate.

(Embodiment 6)
Next, a sixth embodiment of the present invention will be described. In the present embodiment, as shown schematically in FIGS. 23A to 23C, digital components (Ethernet PHY IC 230, PLC IC 210, memory IC 220) are mounted on the first surface 200a of the PLC module 200. Since the balanced filter 260 is mounted on the second surface 200b facing the first surface 200a and the second surface 200b faces the mounting substrate (motherboard), the balanced filter 260 is used. However, it is possible to avoid the influence of noise from the digital parts and to reduce the noise.

  In addition, digital components mounted on the first surface 200a are connected via a resistor 213 as the built-in circuit component. Here, FIG. 23A is a sectional view, FIG. 23B is a diagram showing the first surface, and FIG. 23C is a diagram showing the second surface. DA represents the digital domain, and AA represents the analog domain.

  With this configuration, even if unwanted radiation occurs due to mismatch between the characteristic impedance and resistance of the wiring, the resistance is a built-in circuit component, so this wiring is also confined in the built-in part, and unwanted radiation is contained within the board. Can be confined. Moreover, not only can the connection wiring between the digital components be built-in, but it can also be formed as an inner layer in the laminated substrate, facilitating wiring and reducing the wiring length. In addition, the distance between the digital parts can be reduced to the maximum, and wiring for connecting the digital parts and the built-in circuit parts can be inserted into the built-in part. By reducing the distance between the digital parts, the wiring length between the digital parts can be shortened, and the signal loop that causes the unnecessary radiation can be reduced. Therefore, unnecessary radiation can be reduced.

  As described above, the present invention is not limited to the electronic circuit board for PLC communication, but can be effectively applied to any electronic circuit board on which digital parts and analog parts are mounted.
  That is, the present invention provides a substrate on which a digital component is mounted on a first surface and an analog component is mounted on a second surface opposite to the first surface, and a second surface of the substrate. And a connection portion connected to the mounting substrate.
  According to this configuration, the digital component is mounted on the first surface, the analog component and the connection portion are mounted on the second surface facing the first surface, and the second surface faces the mounting substrate. Therefore, the heat generated from the digital component is efficiently radiated from the first surface of the substrate and the second surface side is radiated to the second surface side. Can be prevented from being accumulated.

  In the electronic circuit device of the present invention, the digital component, the analog component, and the digital component are mounted on the first surface, and the analog component is mounted on the second surface facing the first surface. And a connection portion provided on the second surface of the substrate and connected to the mounting substrate.
  According to this configuration, the digital component having a large calorific value is mounted on the first surface, and the analog component having a small calorific value and the connecting portion are mounted on the second surface facing the first surface. Since the second surface faces the mounting substrate, it is possible to prevent heat from being accumulated in the electronic circuit substrate. Further, from the first surface of the substrate, heat generated from the digital component is efficiently radiated, and an electronic circuit with high reliability can be provided by suppressing the influence of heat.

  According to the present invention, in the electronic circuit device, the analog component includes a heat generating component arranged so as to avoid a position facing the digital component in a plane.
  With this configuration, the influence of heat transmitted through the substrate can be avoided.

  According to the present invention, in the electronic circuit device, the heat generating component is an amplifier (op amp).
  With this configuration, the operational amplifier generates a large amount of heat and is susceptible to noise, but avoids the effect of heat transmitted through the board because it is placed away from the position facing the digital component in a plane. can do.

  In the present invention, the electronic circuit device includes a heat dissipating member that contacts the digital component.
  According to this configuration, since the heat radiating member that comes into contact with the digital component is provided, the heat radiating member plays a role of forcibly releasing heat. For this reason, the heat from the digital component is efficiently radiated from the first surface of the substrate, and heat does not flow into the second surface, so that the influence of heat can be blocked.

  According to the present invention, in the electronic circuit device, the first surface of the substrate is provided with a heat radiating member via an insulating elastic member.
  With this configuration, the height of the component mounted on the first surface of the substrate can be absorbed by this elastic member, and the adhesion can be increased, so that the thermal contact property can be improved and the heat dissipation can be further improved. .

  In the present invention, in the electronic circuit device, the digital component includes one that performs at least one of a modulation process and a demodulation process of a multicarrier signal. Here, even an integrated circuit that performs both modulation and demodulation processing is effective.

  According to the present invention, in the electronic circuit device, the multicarrier signal includes a power line communication signal that can be transmitted to a power line having a pair of lines.
  According to this configuration, since the digital component that performs at least one of the modulation processing and the demodulation processing of the multicarrier signal is arranged on the surface opposite to the heat generating component, the influence of heat can be reduced.

  In the present invention, the electronic circuit device may further include a filter that is mounted on the second surface and that blocks a predetermined frequency band for the power line communication signal. It is.
  According to this configuration, the digital component that performs at least one of the modulation processing and the demodulation processing of the multicarrier signal and the filter are respectively mounted on different surfaces of the substrate and are shielded from each other by the substrate. It is possible to suppress the influence of noise caused by digital parts from reaching the filter. Further, by using a laminated substrate as the substrate, the shielding effect between the first surface and the second surface can be further enhanced. In addition, by using a laminated substrate composed of a plurality of conductive layers laminated via an insulating layer, a ground terminal and a ground layer can be connected without using a through via. Even when the mounting area of the filter is increased, both surfaces of the multilayer substrate can be efficiently used as mounting surfaces, and as a result, the electronic circuit device can be reduced in size.

  In the present invention, in the electronic circuit device, the filter includes a balanced filter having substantially the same impedance as viewed from each of the pair of lines.
  According to this configuration, it is possible to reduce the influence of noise on the balanced filter by mounting the balanced filter on the surface facing the digital component. Also, a balanced filter that is usually mounted with a combination of chip components such as a chip inductor and a chip capacitor tends to have a large mounting area. However, according to this configuration, the mounting area of the balanced filter used for power line communication is large. Even if it becomes, size reduction of an electronic circuit board can be achieved.

  According to the present invention, in the electronic circuit device, the power line communication signal output from the electronic circuit device is superimposed on the AC voltage transmitted to the power line, and the power line communication signal is separated from the AC voltage transmitted to the power line. And a power line communication device including a coupler that outputs to the mounting board.
  According to this configuration, it is possible to provide a power line communication device that can perform high-speed communication and has low noise and high reliability.

  According to the present invention, in the electronic circuit device, the substrate includes a first laminated substrate having a plurality of conductive layers laminated through an insulating layer therein, and a plurality of conductive layers laminated through the insulating layer. A second laminated substrate different from the first laminated substrate, and interposed between the first laminated substrate and the second laminated substrate, and the first laminated substrate, The first laminated substrate is laminated, and the first laminated substrate and an insulating sheet provided with a conductive path that electrically connects the second laminated substrate are included.
  With this configuration, it is possible to provide a small and low-noise electronic circuit device.

  In the present invention, the electronic circuit device includes a built-in circuit element provided on the insulating sheet and built in the electronic circuit board, wherein the built-in circuit element is surrounded by the conductive path.
  According to this configuration, it is possible to perform reliable shielding with a simple configuration by forming the conductive path with a conductive paste or the like. Moreover, you may make it cover with copper foil.

  According to the present invention, in the electronic circuit device, the multilayer substrate and the other multilayer substrate include ones having the same substrate thickness.
  According to this configuration, since the thicknesses of the substrates are configured to be equal, the two laminated substrates due to a difference in substrate thermal expansion during a temperature change such as a heat shock and the insulating sheet provided with the conductive path It is possible to prevent peeling and improve the connection reliability of the conductive path connecting the two laminated substrates.

  According to the present invention, the electronic circuit device includes a built-in circuit element provided on the insulating sheet and built in the substrate, wherein the plurality of built-in circuit elements includes a thickness of the substrate and the other substrate. The one mounted on the thicker substrate.
  According to this configuration, even if the substrate is thinned, circuit components are mounted only on the thicker substrate, so that the warp of the thin substrate is prevented, and two layers are laminated when laminated with an insulating sheet having a conductive path, that is, a composite sheet. It becomes possible to improve the connection reliability of the conductive path connecting the laminated substrates.

  In the present invention, in the electronic circuit device, the insulating sheet includes an inorganic filler and a thermosetting resin.
  According to this configuration, it is possible to control the thermal expansion coefficient, dielectric constant, and thermal conductivity by selecting an inorganic filler, improving the connection reliability of the conductive path connecting the two laminated substrates, and heat dissipation Can be improved.

  In the present invention, in the electronic circuit device, the insulating sheet contains 70 wt% to 95 wt% of an inorganic filler and a thermosetting resin.
  According to this configuration, the coefficient of thermal expansion can be matched with that of the two laminated substrates, and the two laminated substrates and the conductive material in the case of a temperature change such as a heat shock due to a difference in thermal expansion between the insulating sheet and the two laminated substrates. It is possible to prevent peeling from the insulating sheet provided with a path, and to improve the connection reliability of the conductive path connecting the two laminated substrates. In addition, when the insulating sheet and the two laminated substrates are laminated, the pressure applied to the circuit component mounted on the surface in contact with the insulating sheet can be suppressed, and damage to the circuit component can be prevented. The laminated substrate is formed by sandwiching an insulating layer between conductive layers on which a desired pattern is formed. This insulating layer can also be composed of an inorganic filler and a thermosetting resin. When this insulating sheet is made of a thermosetting resin having a lower curing temperature than the insulating layer constituting the laminated substrate, the insulating layers of the laminated substrate are heat-treated when the laminated substrates are fixed together via the insulating sheet. It is possible to prevent the deterioration.

  According to the present invention, in the electronic circuit device, the connector is provided in the vicinity of one end of the substrate, and the heat generating component is provided at an end edge on a diagonal line with respect to the connection portion.
  According to this configuration, since the heat generating component is provided at a position far from the connector, the heat from the heat generating component can be dissipated before reaching the connector. Further, by disposing a heat sink on the first surface side of the substrate, heat can be efficiently radiated.

  In the present invention, the electronic circuit device described above includes an electronic circuit device in which a heat dissipation member is provided on the first surface of the substrate. With this configuration, the thermal contact property can be improved, and the heat dissipation property can be further improved.

  According to the present invention, in the electronic circuit device, the first surface of the substrate is provided with a heat radiating member via an insulating elastic member. With this configuration, the height of the component mounted on the first surface of the substrate can be absorbed by this elastic member, and the adhesion can be increased, so that the thermal contact property can be improved and the heat dissipation can be further improved. .

  According to the present invention, in the electronic circuit device, the connection portion is provided in the vicinity of one end of the second surface of the substrate, and the heat generating component is provided in the vicinity of the other end of the second surface of the substrate. Included.
  According to this configuration, since the heat generating component is provided at a position far from the connector, the heat from the heat generating component can be dissipated before reaching the connector.

  It should be noted that the integrated circuit constituting the digital component that is the subject of the present invention is not necessarily a modulation / demodulation circuit such as a main IC, and is applied to the mounting of an integrated circuit having a large number of ground terminals, such as an AFE / IC. Is possible.

  With the above configuration, the digital component is mounted on the first surface, the analog component and the connection portion are mounted on the second surface facing the first surface, and the second surface faces the mounting substrate. Therefore, heat from the digital component is efficiently radiated from the first surface of the board, and heat is accumulated in the electronic circuit board because the second surface side is radiated to the second surface side. Can be prevented.
  Also, among the analog components, digital components such as an amplifier with a large calorific value are mounted on the first surface, and analog components having a large calorific value and a connecting portion are mounted on the second surface opposite to the first surface. Since the second surface faces the mounting substrate, heat can be prevented from being accumulated on the substrate, and heat from the digital component can be efficiently radiated from the first surface of the substrate. be able to.
  In addition, a multilayer substrate in which a plurality of conductive layers are formed with an insulating layer interposed therebetween is used as a substrate, and a digital component such as an Ethernet (registered trademark) PHY IC configured to perform signal processing of a multicarrier signal is mounted. In the electronic circuit device, the conductive layer disposed closest to the integrated circuit among the plurality of conductive layers constituting the multilayer substrate is electrically connected to the plurality of ground terminals, whereby the ground terminal The distance between the conductive layer and the conductive layer is the shortest, and the ground terminal and the conductive layer can be connected while maintaining the processing accuracy without forming a via hole (through via) penetrating the laminated substrate.

  According to the electronic circuit board and the electronic circuit device of the present invention, the mounting position of the heat generating component such as an operational amplifier is placed on the surface opposite to the digital component, and is arranged away from the connection portion, so that heat dissipation is achieved. Since it can be configured so as not to be affected by noise, it can be applied to various fields such as high-speed power line communication.

The perspective view which shows the state which mounted the PLC circuit module using the electronic circuit board of Embodiment 1 of this invention in the motherboard 110 Sectional explanatory drawing which shows the state which mounted the PLC circuit module using the electronic circuit board of Embodiment 1 of this invention in the motherboard 110 Cross-sectional main part explanatory drawing which shows the PLC circuit module using the electronic circuit board of Embodiment 1 of this invention The figure which shows the layout of the upper surface of the electronic circuit board which comprises the PLC circuit module of Embodiment 1 of this invention The figure which shows the upper surface of the electronic circuit board which comprises the PLC circuit module of Embodiment 1 of this invention, a lower surface, and a built-in component. The figure which shows the external appearance of the PLC modem of Embodiment 1 of this invention Sectional drawing of PLC modem of Embodiment 1 of this invention 1 is a block diagram showing an example of hardware of a PLC modem according to a first embodiment of the present invention. Schematic functional block diagram of an example of a digital signal processing unit realized by the PLC / IC 210 of the PLC module according to the first embodiment of the present invention. 1 is an equivalent circuit diagram showing a balanced filter used in the PLC circuit module according to the first embodiment of the present invention. The figure which shows the structure of the 2nd laminated substrate used for the PLC circuit module of Embodiment 1 of this invention. (A)-(f) is a perspective view which shows one Embodiment of the manufacturing process of the PLC module of Embodiment 1 of this invention. (A)-(f) is sectional drawing which shows one Embodiment of the manufacturing process of the PLC module of Embodiment 1 of this invention (A)-(f) is sectional drawing which shows the manufacturing process of the 1st laminated substrate used for the PLC module of Embodiment 1 of this invention. Explanatory drawing which shows the PLC circuit module of Embodiment 2 of this invention. Explanatory drawing which shows the PLC circuit module of Embodiment 3 of this invention. Explanatory drawing which shows the result of having measured the in-plane electromagnetic field distribution of the PLC circuit module of Embodiment 1 of this invention Operation explanatory diagram of the first multilayer substrate of the PLC circuit module according to the first embodiment of the present invention. Explanatory drawing of the PLC circuit module of Embodiment 4 of this invention Explanatory drawing of the PLC circuit module of a comparative example Explanatory drawing of the PLC circuit module of Embodiment 5 of this invention Explanatory drawing of the PLC circuit module of a comparative example Explanatory drawing of the PLC circuit module of Embodiment 6 of this invention (a) is sectional drawing, (b) is a top view which shows a 1st surface, (c) is a top view which shows a 2nd surface

11, 12, 13, 14, 15, 16 Metal layer 15 Ground layer 100 PLC modem 101 Case 102 Power connector 103 RJ45 connector 105 Display unit 200 (for PLC) circuit module 210 PLC / IC
211 CPU
212 PLC / MAC block 213 PLC / PHY block 220 AFE / IC
221 DA converter (DAC)
222 AD converter (ADC)
223 Variable Amplifier (VGA)
230 Ethernet PHY IC
251 Low-pass filter 252 Operational amplifier (driver IC)
260 Balanced filter (bandpass filter)
270 Coupler 271 Coil transformer 272a, 272b Coupling capacitor 300 Switching power supply 400 Power plug 500 Outlet 600 Power cable 900 Power line 2110 Control unit 2111 Symbol mapper 2112 Serial-parallel converter 2113 Inverse wavelet converter 2114 Wavelet converter 2115 Parallel-serial Converter 2116 Demapper