JP2009280129A - Car-mounted electronic controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress a noise obstacle to a CPU or the like from a relay or the like. <P>SOLUTION: A power circuit in which at least a relay 22 is mounted, and a main signal circuit in which signal system electric components including at least a CPU 32, are formed in different circuit boards (power circuit board 21 and a main signal circuit board 31), respectively. A sub signal circuit in which signal system electric components other than the CPU are provided separately from the main signal circuit, and this sub signal circuit is interposed between the power circuit board 21 and the main signal circuit board 31, in the state where a circuit board (sub signal circuit board 41) different from the power circuit board and the main signal circuit board, is installed. The sub signal is ground-connected to the ground of a power circuit different from that of the main signal circuit. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an on-vehicle electronic control device (hereinafter referred to as “ECU”) accommodated in an electric junction box for automobiles, and more particularly to an ECU capable of reducing noise disturbance.

  The ECU is configured such that a circuit board on which an electrical component is mounted on a printed wiring board is housed in a case, and the mounted electrical component differs depending on the vehicle type, grade, and destination.

  In addition, since the circuit board housed in the ECU requires a large number of electrical components and a plurality of circuits, the circuit board uses a high current wiring board such as a bus bar.

  However, since the ECU differs depending on the vehicle type as described above, the wiring board for large current needs to have various shapes.

  However, the bus bar has a problem that it is large in size and heavy, and has become difficult to meet the recent needs for downsizing and weight reduction.

  Under such circumstances, as disclosed in Patent Documents 1 and 2 below, proposals have been made to reduce the dependency on the bus bar.

  Further, as disclosed in Patent Documents 1 and 2, the substrate is divided into a power substrate including a high current power circuit and a signal substrate including a low current signal circuit. Since it is necessary to connect the individual substrates, the connection is performed using a jumper or the like.

  However, when juxtaposed using jumpers as described above, in circuit design, it is necessary to provide a part of either the power circuit or the signal circuit on the same substrate as the other circuit.

  For example, when a part of the power circuit is provided on the signal board, the current path of the power circuit becomes long, and there is a problem that noise easily propagates from there to the signal circuit on the signal board.

Further, when a part of the signal circuit is provided on the power board, a problem that noise generated from the power circuit easily propagates to the signal circuit on the power board occurs.
JP 2006-93210 A JP 2001-16746 A

  Accordingly, the main object of the present invention is to obtain an on-vehicle electronic control device that can suppress noise disturbance.

  According to the present invention, a power circuit for mounting a noise generating electrical component serving as a noise generating source and a main signal circuit for mounting a signal electrical component that is a signal system are formed on separate circuit boards, respectively, and the main signal circuit Separately, a sub-signal circuit for mounting a signal system electrical component is provided, and the sub-signal circuit is mounted on a circuit board different from the main signal circuit between the main signal circuit and the power circuit. And the ground of the sub signal circuit is connected to the ground of the power circuit different from the ground of the main signal circuit.

  As an aspect of the present invention, the signal system electrical component of the main signal circuit is a signal system electrical component including a CPU, and the signal system electrical component of the sub signal circuit is a signal system electrical component other than the CPU. it can.

  Further, as an aspect of the present invention, the sub signal circuit can be mounted on a circuit board different from the power circuit.

  In this case, the circuit board on which the sub-signal circuit is mounted can be provided at a position straddling the power circuit board on which the power circuit is formed and the main signal circuit board on which the main signal circuit is formed.

  A circuit board on which the sub-signal circuit is mounted can be provided via a resin housing.

  As an aspect of the present invention, the main signal circuit can be formed by mounting a common signal system electrical component, and the sub signal circuit can be formed by mounting a signal system electrical component according to specifications.

  The above specification includes the classification by vehicle type, grade, or destination.

  According to this invention, the vehicle-mounted electronic control apparatus which can suppress a noise disturbance can be obtained.

An embodiment for carrying out the present invention will be described below with reference to the drawings.
FIG. 1 is a schematic diagram showing the structure of an in-vehicle electronic control unit, that is, an ECU 11. As shown in this figure, the ECU 11 is configured by housing a plurality of circuit boards 21, 31, 41 in a case 51. Yes.

  There are three types of circuit boards 21, 31 and 41, respectively. A power circuit board 21 mounted with a power circuit 25 (see FIG. 2) on which an electrical component that requires a high current as a noise generating electrical component such as a relay 22 is mounted, and a CPU (Central Processing Unit) ) A sub signal having a main signal circuit board 31 on which a main signal circuit 35 for mounting a signal system electrical component such as 32 is mounted and a sub signal circuit 45 for mounting a signal system electrical component other than the CPU. This is a circuit board 41. The main signal circuit 35 corresponds to a conventional signal circuit. The main signal circuit board 31 may have only the communication circuit mounted without the CPU 32.

  In addition to the relay 22 and the like, a connector 23 is mounted on the power circuit board 21.

  On the main signal circuit board 31, electrical components centered on the CPU 32 and a connector 33 are mounted. The main signal circuit 35 mounted on the main signal circuit board 31 can be used in common in the ECU 11 manufactured for each vehicle type, grade, or destination. One or several types are prepared.

  The sub-signal circuit board 41 is mounted with electrical components other than the CPU that is vulnerable to noise, but the mounted sub-signal circuit 45 has different specifications for each vehicle type, grade, and destination. Many types of sub-signal circuit boards 41 are prepared.

  That is, by selecting the sub-signal circuit board 41, it is possible to obtain ECUs 11 corresponding to various vehicle types, grades, and destinations.

These circuit boards 21, 31, 41 are connected as follows.
The power circuit board 21 and the main signal circuit board 31 are juxtaposed in a separated state, and the sub signal circuit board 41 is connected so as to straddle the end portions of the power circuit board 21 and the main signal circuit board 31. The connection is made through a housing 61 made of resin that is H-shaped when viewed from the front.

  That is, the sub-signal circuit board 41 is horizontally fixed in the groove-shaped space on the upper side of the housing 61 with the edge 41a fitted therein, and the sub-signal circuit board 41, the power circuit board 21, and the main signal circuit board 31 are fixed. Are connected by a plurality of rod-like terminals 63.

  Then, as shown in FIG. 2, the ground G1 of the power circuit 25 and the ground G2 of the main signal circuit 35 are separated, and the sub-signal circuit 45 is connected to the ground G1 (frame ground) of the power circuit 25. One point ground.

  In the ECU 11 configured as described above, the power circuit 25, the main signal circuit 35, and the sub signal circuit 45 are formed on different circuit boards, and the sub signal circuit 41 is connected to the ground of the main signal circuit 35. It is connected to the ground G1 of the power circuit 25 different from G2.

  For this reason, it is possible to prevent noise propagating by conduction or radiation (radiation) from entering the main signal circuit 35 from the power circuit 25 having a noise generation source such as the relay 22.

  In addition, since the sub signal circuit 45 is mounted on a circuit board (sub signal circuit board 41) different from the power circuit board 21, the propagation of noise to the main signal circuit 35 can be better suppressed.

  In addition, since the sub signal circuit board 41 is provided at a position straddling the power circuit board 21 and the main signal circuit board 31, it is possible to suppress the length in the direction in which the circuit boards 21, 31, 41 are arranged from becoming long. Can do.

  Further, a sub signal circuit board 41 is provided via a resin housing 61. Therefore, it becomes difficult to be influenced by noise.

  Further, the lower end 61a of the housing 61 protrudes under the power circuit board 21 and the main signal circuit board 31 as shown in FIG. 1, and is fixed by press-fitting or heat welding. For this reason, since the power circuit board 21 and the main signal circuit board 31 can be fixed by the housing 61, it is also effective when the terminals 63 are soldered.

  In addition, a common circuit is mounted on the main signal circuit board 31 for the vehicle type, grade, and destination, and a circuit for each specification that is different for each vehicle type, grade, and destination is mounted on the sub-signal circuit board 41. For this reason, it is possible to flexibly cope with the vehicle type and grade by appropriately selecting the sub signal circuit board 41 to be used. That is, it is possible to realize easy manufacturing by facilitating changeover and reducing process manufacturing.

  Further, since the bus bar can be omitted, the above-described changeover can be facilitated and the cost can be reduced.

  The noise generation source of the present application includes a relay, a buzzer, a motor, a solenoid, a lamp for dimming control, and the like, and these indicate an inductance load or a PWM control (ON / OFF is performed at high speed) load.

The above is one form for implementing this invention, This invention is not limited only to said structure, Other forms can be employ | adopted.
For example, the sub-signal circuit can be mounted on the power circuit board.

Sectional drawing which shows schematic structure of ECU. Explanatory drawing which shows the installation structure of each circuit.

Explanation of symbols

11 ... ECU
21 ... Power circuit board 22 ... Relay 25 ... Power circuit 31 ... Main signal circuit board 32 ... CPU
35 ... Main signal circuit 41 ... Sub signal circuit board 45 ... Sub signal circuit 61 ... Housing G1, G2 ... Ground

Claims (6)

A power circuit for mounting a noise generating electrical component as a noise generation source and a main signal circuit for mounting a signal system electrical component which is a signal system are formed on separate circuit boards, respectively.
In addition to the main signal circuit, a sub-signal circuit for mounting signal system electrical components is provided,
The sub signal circuit is interposed between the main signal circuit and the power circuit in a state of being mounted on a circuit board different from the main signal circuit,
A vehicle-mounted electronic control device in which the ground of the sub signal circuit is connected to the ground of the power circuit different from the ground of the main signal circuit. The in-vehicle system according to claim 1, wherein the signal system electrical component of the main signal circuit is a signal system electrical component including a CPU, and the signal system electrical component of the sub signal circuit is a signal system electrical component other than the CPU. Electronic control device. The in-vehicle electronic control device according to claim 1, wherein the sub signal circuit is mounted on a circuit board different from the power circuit. The in-vehicle electronic control device according to claim 3, wherein the circuit board on which the sub signal circuit is mounted is provided at a position straddling the power circuit board on which the power circuit is formed and the main signal circuit board on which the main signal circuit is formed. . The on-vehicle electronic control device according to claim 4, wherein a circuit board on which the sub signal circuit is mounted is provided via a resin housing. The main signal circuit is formed by mounting a common signal system electrical component,
The on-vehicle electronic control device according to any one of claims 1 to 5, wherein the sub-signal circuit is formed by mounting a signal electric component according to specifications.

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