JP2002084054A - Electronic controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the size and assembling man-hours of an electronic controller which is constituted by mounting a plurality of mounting substrates joined to a common heat radiating member on a main substrate. SOLUTION: The mounting substrates 12a-12c respectively mounted with power transistors 10a-10c are mounted on the main substrate in a state where the substrates 12a-12c are collectively joined to one heat radiating member 14. Of the signal lines formed on the substrates 12a-12a, those for common signals are electrically connected to each other through the wiring pattern 32 of the heat radiating member 14. Consequently, it becomes unnecessary to provide connecting terminals used for connecting the signal lines connected to each other through the wiring pattern 32 of the member 14 on the mounting substrates 10a-10c.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic control device in which a plurality of mounting boards joined to a common heat radiation member are connected to a main board.

[0002]

2. Description of the Related Art Conventionally, for example, as shown in FIG.
Electronic components having heat generation 110a, 110b, 110c
(E.g., power transistors, power ICs, etc.) on each of a plurality of substrates 112a, 112b, 112
c (hereinafter, referred to as “mounting board”) in a state of being joined to the common heat radiation member 114,
A configuration has been proposed in which a to 112c are mounted on a common substrate 116 (referred to as a "main substrate" in this specification) (for example, Japanese Patent Application Laid-Open No. H11-186687).

According to this configuration, the heat-generating electronic component 11
0a to 110c can be efficiently dissipated by the heat radiating member 114 and the main substrate 116
In this case, the mounting space and the number of assembling steps of the plurality of mounting boards 112a to 112c can be reduced, so that the electronic control device can be reduced in size and cost.

[0004]

In order to further reduce the size of the electronic control unit in such a configuration, each mounting board 11
It is conceivable to reduce the size of each of the mounting substrates 112a to 112c by further increasing the integration of the circuits on the 2a to 112c. However, each of the mounting boards 112a to 112c
In order to assemble the main board 116 with the main board 116, a predetermined width (about “the number of the connection terminals 118 for connecting each mounting board and the main board” × “the interval between the connection terminals 118”) is required. It is necessary to secure it, and miniaturization of the main substrate 116 is limited.

The same type of wiring (for example, various signal lines such as a power supply line, a GND line, and a bus line) common to each of the mounting boards 112a to 112c is connected to a connection terminal provided on each of the mounting boards 112a to 112c. The configuration is such that the components are guided to the main board 116 via 118 and connected to each other by the main board 116 (see FIG. 4B). That is, the number of connection terminals 118 corresponding to the signals common to the respective mounting substrates 112a to 112c is required for the number of the mounting substrates 112a to 112c.

For this reason, when the mounting substrate is finely divided into functions (that is, when a single mounting substrate is divided into a plurality of substrates), each mounting substrate 112a
To 112c, the heat dissipating member 114, and the main board 116, and the number of assembly steps increases. In order to solve such a problem, it is conceivable to reduce the interval between the connection terminals 118. However, it is not easy to assemble the mounting boards 112a to 112c to the main board 116, so that there is a limit.

In view of the above, the present invention has been made to further reduce the size and the number of assembling steps of an electronic control device in which a plurality of mounting substrates bonded to a common heat radiation member are mounted on a main substrate. The purpose is to be able to promote.

[0008]

In order to solve the above-mentioned problems, according to the present invention (claim 1), a plurality of mounting boards on which heat-generating electronic components are mounted are mounted on an electronic board. In an electronic control unit that is joined to a common heat dissipation member for absorbing and dissipating heat from components and electrically connected to a common main board, wiring is provided to a heat dissipation member to which a plurality of mounting boards are joined. Is formed. Then, among the wirings respectively formed on the plurality of mounting boards, the same kind of wiring having a common signal (hereinafter simply referred to as “the same kind of wiring”) is electrically connected to each other via a signal transmission path formed on the heat radiation member. Connected.

Here, the "same kind of wiring" means a wiring having a common signal as described above. The signal includes a power source (for example, +12, +5, etc.), GND, a clock signal,
Command signals, data signals, and the like can be considered. That is, in the electronic control device of the present invention (claim 1), instead of conducting the same kind of wiring common to the mounting boards on the main board and connecting them to each other, a signal transmission formed on the heat dissipation member is performed. They are connected via routes. Therefore, in order to electrically connect the same kind of wiring connected via the signal transmission path formed on the heat radiating member to the main board, there is no need to provide connection terminals for each mounting board and connect to the main board. The electrical connection between the signal transmission path of the heat dissipating member and the main board may be made at any one location.

Therefore, according to the electronic control device of the present invention (claim 1), the number of connection terminals to be provided between the mounting board and the main board can be reduced, and the size of the mounting board can be reduced. The size of the heat dissipating member on which is mounted and the size of the main board can also be suppressed, the size of the device can be reduced, and the number of steps for assembling the connection terminals to the main board can be reduced. With such a reduction in size and man-hours, a significant cost reduction can be realized.

The "signal transmission path formed on the heat radiating member" may be a wiring pattern formed on the surface of the heat radiating member by a printed wiring technique or other various wirings, and the heat radiating member may be formed of a conductor. If so, the heat radiation member itself is included.

By the way, various modes can be considered for electrically connecting the signal transmission path of the heat radiating member to the main board.
In the case where a general-purpose mounting board commonly used by a plurality of electronic control devices is provided as one of the plurality of mounting boards, the general-purpose mounting board is configured as described in claim 2. It is preferable that the signal transmission path of the heat radiating member is electrically connected to the main board through the intermediary.

As a general-purpose mounting substrate, for example, a substrate on which a general-purpose circuit such as a power supply circuit is formed can be considered.
If the signal transmission path of the heat radiating member is electrically connected to the main board through a general-purpose mounting board commonly used in each of these models, it is not necessary to perform the other mounting boards. . In other words, other mounting boards can be freely selected according to the model without special consideration of the electrical connection between the signal transmission path of the heat radiation member and the main board, and the effect of increasing the degree of freedom in design is increased. Play.

As described above, various types of "same type wiring" are conceivable. For example, as described in claim 3, the same type of wiring includes a power supply wiring and a heat radiating member. May be connected via the signal transmission path.
The connection terminals used for power supply tend to have a large cross-sectional area to withstand the current, but by electrically connecting the power supply wires via the signal transmission path of the heat dissipation member By reducing the number of connection terminals for power supply connecting the mounting board and the main board, the size of the mounting board, the main board, the heat radiation member, etc. can be reduced more effectively.
That is, the size of the device can be reduced. The power supply wiring includes a power supply line (for example, a power supply line having various voltages such as a +12 power supply line) and a GND line.

Further, as the same kind of wiring, a common bus to a plurality of mounting boards may be connected via wiring of a heat radiation board. A bus is composed of a plurality of wirings. By connecting the wirings constituting the buses electrically through a signal transmission path of a heat radiating member, a connection for power supply connecting the mounting board and the main board is provided. If the number of terminals is reduced, the size of the mounting substrate, the main substrate, the heat radiating member, and the like can be reduced more effectively, that is, the size of the device can be reduced.

Since the parallel bus requires a relatively large number of signal lines, the same type of wiring may be used as a parallel bus, and the signal transmission path of the heat radiating member may be changed. If the connection is made through the connection, the number of connection terminals can be further reduced.

The same kind of wirings connected to each other via the signal transmission path of the heat radiating member may be configured to transmit an internal signal of the electronic control device (a signal used only inside the device). In the case of a wiring for transmitting, the following effects can be obtained.

That is, in the conventional structure, the internal signal is transmitted and received between the mounting board and the main board via the connection terminal provided for each mounting board. In this case, the internal signal is transmitted. Wiring and connection terminals and wiring and connection terminals that transmit external signals (for example, signals for driving a load outside the device, such as signals exchanged between the inside and the outside of the device) are arranged close to each other. May be affected. For example, the influence of EMI or static electricity from the outside of the device along the transmission path of the external signal affects the internal signal, and the radio noise generated in the transmission path of the internal signal affects the external signal.

On the other hand, if the wires for transmitting the internal signals are connected by the signal transmission path of the heat radiating member as the same kind of wires as described in claim 6, each of the wires for transmitting the internal signals is individually provided. It is not necessary to connect to the main board for each mounting board, and even if it is necessary to electrically connect the same kind of wiring connected via the signal transmission path of the heat radiation member to the main board, the connection is made at one place Just make it possible. Therefore, it is possible to arrange the connection terminal for transmitting the internal signal and the connection terminal for transmitting the external signal away from each other, and it is possible to reduce the mutual interference as described above. is there.

[0020]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1A is a perspective view showing the overall configuration of a vehicle electronic control device as one embodiment.

As shown in FIG. 1 (a), the electronic control unit 2 of this embodiment comprises a plurality of mounting boards 12a, 12b, 12c made of a ceramic substrate and having high heat dissipation, and the plurality of mounting boards 12a to 12c. A heat dissipation member 14 to which 12c is joined;
A main board 16 electrically connected to the plurality of mounting boards 12a to 12c and to which the heat radiation member 14 is fixed,
A connector 22 for relaying an electric signal between the main board 16 and an external device. Here, FIG.
The state where the heat radiating member 14 and the connector 22 are assembled to the main board 16 is shown.

The plurality of mounting boards 12a, 12b, 1
2c is divided and classified for each control content, and power transistors 10a to 10c as power elements having heat generation properties and other electronic components are mounted on each of the mounting boards 12a to 12c. This mounting substrate 12a-1
2c is a common heat dissipating member formed of a material having excellent heat conductivity (in this embodiment, aluminum and having conductivity) in order to efficiently absorb and radiate heat generated in the power transistors 10a to 10c. 14 are bonded via an adhesive 15. The adhesive 15 preferably has a high thermal conductivity, for example, a silicon adhesive. The mounting boards 12a to 12c and the main board 16 are electrically connected by soldering in a state where the connection terminals 18a to 18c projecting from the mounting boards 12a to 12c are inserted into the through holes of the main board 16. It is connected to the.

The heat dissipating member 14 is fixed to the main board 16 using screws 20. The connector 22 is connected to the main board 1.
6 is fixed using screws 24 in the vicinity of the edge of one side, and is electrically connected to the main board 16 via connector pins 26. In this manner, the mounting substrates 12a to 12c,
The main board 16 on which the heat radiating member 14 and the connector 22 are assembled is housed in a case 28 made of a material having high thermal conductivity (eg, aluminum) as shown in FIG. Is configured. The mounting boards 12a to 12c, the heat radiating member 14, and the connector 22 are also housed in the case 28, but the external connection terminals (not shown) of the connector 22 face the outside of the case 28 from the opening 28a of the case 28. .

FIG. 2 is an explanatory view showing in detail how the mounting substrates 12a to 12c are provided on the surface of the heat radiating member 14, and FIG. 3 is a sectional view taken along the line AA in FIG. As shown in FIG. 2 or FIG. 3, on the surface of the heat radiating member 14, a wiring insulated from the heat radiating member 14 via the first insulating layer 30 is provided on the surface to which the mounting boards 12 a to 12 c are joined. A pattern 32 is formed. In the wiring pattern 32, lands 34a to 34c for connecting to the plurality of mounting substrates 12a to 12c are formed.
The wiring pattern 32 is the second
Of the insulating layer 36. The wiring pattern 32
Corresponds to a “signal transmission path” in the claims.

Then, as shown in FIG. 3, the second insulating layer 36
Are mounted on the mounting substrates 12a to 12c via an adhesive 15.
Are stacked, and the lands 38a to 38c on each of the mounting boards 12a to 12c and the lands 34a to
34c are electrically connected by bonding wires 40a to 40c.

Lands 38 on mounting boards 12a-12c
a to 38c are formed on a part of the signal lines 42a to 42c on the respective mounting boards 12a to 12c. That is, among the signal lines on the mounting boards 12a to 12c, the signal lines 42a to 42c common to the plurality of mounting boards 12a to 12c are electrically connected to each other via the wiring pattern 32 on the heat radiation member 14. It is connected.

More specifically, it is as follows.
In this embodiment, the common signal lines 42a to 42c
Are formed to transmit various signals including internal signals. For more information, see RESET
Signal lines, 5V power lines, 12V power lines, and signal lines (CLK, D0-D
7, READ / WRITE) are common signal lines, and these are electrically connected to each other as independent wirings through independent wiring patterns 32 on the heat radiating member 14. . The wiring pattern 32 of the heat radiating member 14 connecting the common signal lines 42a to 42c is connected to the main board via the mounting board 12a constituting the power supply circuit and the connection terminals 18a provided on the mounting board 12a. 16 are electrically connected.

The mounting substrate 1 on which the power supply circuit is formed
Reference numeral 2a denotes a circuit board for supplying power to the other mounting boards 12b, 12c, and the like, which is commonly used by a plurality of types of electronic control devices. In a range of models in which the mounting substrate 12a on which the power supply circuit is formed is commonly used, the wiring pattern 32 of the heat radiation member 14
It is electrically connected to the main board 16 via the connection terminals 18a of the mounting board 12a. In this regard, this mounting substrate 1
2a corresponds to a “general-purpose mounting board” in the claims.

On the other hand, the mounting substrate 1 on which the power supply circuit is formed
On the other mounting boards 12b and 12c other than 2a, an electronic circuit for driving an actuator external to the electronic control device 2 and controlling the operation thereof is formed, and connection circuits provided on these mounting boards 12b and 12c are formed. A drive signal (drive current) for driving an external actuator is output from the terminals 18b and 18c, and further output to the outside via the connector 22.

As described above, the internal signals (D0 to D7, CLK
The connection terminal 18a for transmitting a signal, a RESET signal, and a READ / WRITE signal) is disposed apart from the connection terminals 18b and 18c for transmitting a drive signal which is an external signal.
The GND line of each of the mounting boards 12a to 12c is connected to the heat dissipating member 14 via bonding wires 41a to 41c.
It is connected to the main body, and further connected to GND of the main board 16 via the heat radiation member 14. In this regard, the heat dissipation member 14 itself also functions as a “signal transmission path” in the claims.

The structure on the heat radiating member 14 as described above can be formed by the following procedure. First, the insulating layer 30 and the wiring pattern 32 are sequentially stacked on the heat radiation member 14, and lands 34 a to 34 c are formed on the wiring pattern 32. Then, the wiring pattern 32 is covered with the insulating layer 36 so that the lands 34a to 34c are not covered. Then, the mounting substrates 12a to 12c on which the power transistors 10a to 10c and other electronic components are mounted are attached to the insulating layer 36 with the adhesive 15 therebetween.
Lands 38a to 38c on the mounting boards 12a to 12c and the lands 34a to
By bonding the bonding wires 40a to 40c to the bonding wires 34c, the two are electrically connected to each other.

The electronic control unit 2 configured as described above has the following effects. That is, a plurality of mounting substrates 12a on which the power transistors 10a to 10c are mounted.
To 12c are collectively joined to one heat radiation member 14 and mounted on the main board 16 in a united state. And
A signal line having a common signal among signal lines formed on each of the plurality of mounting boards 12a to 12c is connected to the heat radiating member 14.
Are electrically connected to each other via a wiring pattern 32 of the above. Therefore, for the signal lines connected via the wiring patterns 32 of the heat radiating member 14, it is not necessary to provide connection terminals for connecting to the main board 16 on the entire mounting board.

That is, the total number of connection terminals 18a to 18c to be provided between the mounting boards 12a to 12c and the main board 16 can be reduced, and the mounting board 12 having a reduced number of connection terminals can be used.
The sizes of b and 12c can be reduced, the size of the heat dissipating member 14 on which the b and 12c are mounted, and the size of the main board 16 can be suppressed, and the electronic control device can be reduced in size. Also, the number of steps for assembling the connection terminals 18a to 18c to the main board 16 can be reduced. With such a reduction in size and man-hours, a significant cost reduction can be realized.

The wiring pattern 3 of the heat radiating member 14 is provided via the mounting substrate 12a which is used in common among a plurality of models.
2 is electrically connected to the main substrate 16. Therefore, the other mounting boards 12b and 12c can be freely selected according to the model without particularly considering how to electrically connect the wiring of the heat radiation member 14 and the main board 16. This has the effect of increasing the degree of freedom in design.

The power supply wiring (+12 V power line, +5 V power line, GND line) is connected via the heat radiation member 14 and the wiring pattern 32 thereon. Therefore, the total number of connection terminals 18a to 18c for connecting the mounting boards 12a to 12c and the main board 16 can be reduced. Specifically, the mounting boards 12b and 12c, the main board 1
6. It is possible to effectively reduce the size of the heat radiation member 14 and the like, that is, to reduce the size of the electronic control device 2 effectively.

Further, signal lines (CLK, D0, C0, D0) constituting a parallel bus common to the plurality of mounting boards 12a to 12c.
To D7, READ / WRITE) are connected via the wiring pattern 32 of the heat radiation member 14. Therefore, the mounting substrate 12
b, connection terminals 18b for connecting 12c and the main substrate 16;
18c can be reduced. Specifically, in the conventional configuration, “CLK, D0 to D7, READ / WRITE”
Connection terminals corresponding to the ten signals of E
Although it was necessary to provide the connection terminals b and 12c respectively, in the configuration of the present embodiment, this is not necessary.
8b and 18c can be reduced. As a result, the mounting substrate 12
It is possible to further reduce the sizes of the components b, 12c, the main substrate 16, the heat radiation member 14, and the like.

In addition, internal signals (for example, D0 to D7 signals,
The connection terminal 18a for transmitting the CLK signal, the RESET signal, and the READ / WRITE signal) is arranged away from the connection terminals 18b and 18c for transmitting the drive signal which is an external signal. Therefore, even if radio noise occurs in the transmission path of the internal signal, it is possible to suppress the influence on the drive signal, and EMI or static electricity from outside the electronic control unit 2 may intrude along the transmission path of the external signal. Can also suppress the influence on the internal signal.

As described above, one embodiment of the present invention has been described. However, the present invention is not limited to the above-described embodiment, and can take various forms. For example, in the above embodiment, the connection terminals 18a to 18c for electrically connecting the mounting boards 12a to 12c and the main
Although described as being provided so as to protrude from 2a to 12c, the present invention is not limited to this. For example, connection terminals may be formed by laminating conductor patterns on the mounting substrates 12a to 12c.

In the above embodiment, each mounting substrate 12a
The GND lines 12c to 12c have been described as being electrically connected to each other via the heat dissipation member 14 itself, but are not limited to this, and are electrically connected to each other via the wiring pattern 32 of the heat dissipation board 14. You may.
The signal lines that can be connected to each other via the wiring pattern 32 of the heat dissipation board 14 are the above-described signal lines (D0 to D0).
D7 signal).

In the above embodiment, the power transistors 10a to 10c have been described as examples of the "electronic component having heat generation", but the present invention is not limited to this.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an overall configuration of an electronic control device as one embodiment.

FIG. 2 is an explanatory diagram showing a state of connection between a wiring pattern formed on a heat radiation member and a mounting substrate.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a diagram showing a conventional example.

[Explanation of symbols]

 2 ... Electronic control device 10a-10c ... Power transistor 12a-12c ... Mounting board 14 ... Heat dissipation member 16 ... Main board 18a-18c ... Connection terminal 32 ... Wiring pattern 42a-42c ... Signal line

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) BA23 BB08 BD03

Claims (6)

[Claims] An electronic component having a heat generating property includes a plurality of mounting boards each mounted thereon, and the plurality of mounting boards are each used as a common heat radiation member for absorbing and radiating heat from the electronic components. In the electronic control device, which is joined and electrically connected to a common main board, a signal transmission path is formed in the heat radiating member, and a signal is shared among wirings formed on the plurality of mounting boards, respectively. An electronic control unit, wherein the same kind of wirings are electrically connected to each other via the signal transmission path. 2. The electronic control device according to claim 1, further comprising, as one of the plurality of mounting boards, a general-purpose mounting board commonly used by a plurality of models, and the signal transmission path includes: An electronic control unit electrically connected to the main board via a general-purpose mounting board. 3. The electronic control device according to claim 1, wherein the same type of wiring is a power supply wiring. 4. The electronic control device according to claim 1, wherein the same type of wiring is a wiring constituting a bus. 5. The electronic control device according to claim 4, wherein said bus is a parallel bus. 6. The electronic control device according to claim 1, wherein the same type of wiring is a wiring for transmitting an internal signal of the electronic control device.