JP2013069781A - Electronic apparatus - Google Patents

Abstract

An electronic device capable of reliably obtaining noise shielding performance with a simple configuration is provided.
An electronic device includes a mounting substrate, a resin casing as a package for the mounting substrate, and a coating layer made of plating or conductive paint coated on the resin casing, Has a ground connection location that is not covered by the resin casing, and is composed of a conduction location to the ground of the mounting substrate using circuit components of the mounting substrate, or a ground pattern of the mounting substrate. The coating layer coats the resin casing together with the ground connection portions.
[Selection] Figure 1

Description

  The present invention relates to an electronic device that covers a mounting substrate with a casing.

  Generally, a resin casing is used as a casing of an electronic device such as an ECU (Electronic Control Unit) that controls in-vehicle parts.

  FIG. 6 illustrates a configuration example of the electronic device 101 including a resin casing. The electronic device 101 includes a mounting substrate 102 and a resin casing 103 that serves as a package for the mounting substrate 102. The mounting board 102 has a configuration in which components including one or more circuit elements 102b and a connector 102c are mounted on the circuit board 102a. As the material of the resin casing, a resin such as PBT (polybutylene terephthalate) or PPS (polyphenylene sulfide) is used.

  In this type of electronic device, since the casing is a resin casing, noise shielding performance may be inferior to that of a metal casing. Therefore, as a general method for ensuring noise shielding performance for the electronic device, the surface is covered with a shield layer 104 such as plating or conductive paint as shown in FIG.

  Patent Document 1 describes an electronic component package in which a shielding effect is enhanced by grounding a shield layer that covers a sealing body of a mounted component to a GND pattern of a circuit board.

  Patent Document 2 describes an electronic device including a circuit board on which electronic components are mounted on at least one of the front and back surfaces, a board packing tool, and a contact spring. The board packing tool accommodates the circuit board in the internal space and performs electromagnetic wave shielding of the circuit board. The contact spring is made of a metal material, and is mounted on the surface of the circuit board to electrically connect the GND pattern of the circuit board and the board packing tool. The casing of the electronic device is made of resin.

JP 2005-109306 A JP 2010-267928

  However, in the method of covering the surface of the resin casing of the electronic device with a shield layer such as plating or conductive paint as shown in FIG. 6, noise is required unless the connection between the shield layer and the GND pattern of the circuit board is ensured. Shield performance may not be sufficiently secured.

  Moreover, patent document 1 does not provide the shielding effect provision method with respect to a resin housing | casing. Furthermore, it is generally performed in consumer devices such as PCs and portable devices, by applying a conductive paint inside the divided housing and spring-connecting with the GND of the circuit board. The spring connecting parts are separately required.

  The present invention solves the above-described problems, and an object of the present invention is to provide an electronic device that has a resin casing and can reliably obtain noise shielding performance with a simple configuration.

  An electronic device according to the present invention includes a mounting substrate, a resin casing as a package for the mounting substrate, and a coating layer made of plating or conductive paint coated on the resin casing, and the mounting substrate Has a ground connection location that is not covered by the resin casing, and is composed of a conduction location to the ground of the mounting substrate using circuit components of the mounting substrate, or a ground pattern of the mounting substrate. The coating layer coats the resin casing together with the ground connection portions.

  According to the configuration of the present invention, the mounting substrate has a ground connection portion that is not covered with the resin casing and is formed of a conductive portion to the ground of the mounting substrate using circuit components or a ground pattern of the mounting substrate. . And the coating layer which consists of plating or a conductive coating coats a resin housing | casing for every ground connection location. Therefore, it is possible to reliably obtain noise shielding performance with a simple configuration that does not require adding special parts only for connection to the ground.

Sectional drawing which shows the structure of the electronic device which concerns on embodiment of this invention Side view (a) and plan view (b) showing the configuration of the connector provided in the electronic device of FIG. The side view (a) and top view (b) which show the other structure of the connector with which the electronic device of FIG. 1 is provided. Sectional drawing which shows the structure of the electronic device which concerns on other embodiment of this invention. Sectional drawing which shows the structure of the electronic device which concerns on further another embodiment of this invention. Sectional drawing which shows a prior art and shows the structure of an electronic device

[Embodiment 1]
The embodiment of the present invention will be described with reference to FIGS. 1 to 3 as follows.

FIG. 1 shows a configuration of an electronic device 1 according to the present embodiment.
The electronic device 1 is, for example, an in-vehicle ECU, and includes a mounting substrate 2, a resin casing 3, and a coating layer 4.

  The mounting board 2 has a configuration in which circuit components including one or more circuit elements 2b and a connector 2c are mounted on the circuit board 2a. The resin casing 3 is a hollow package with respect to the mounting substrate 2 and covers, for example, the entire circuit board 2a, the entire circuit elements 2b, and the charging parts exposed to the circuit components and the circuit board 2a. The coating layer 4 is made of plating or conductive resin, and coats the resin casing 3.

  The connector 2c includes a housing M and a plurality of pins p that connect the contacts in the housing M to the circuit board 2a. The plurality of pins p include one pin p0 connected to GND (ground) of the circuit board 2a and one or more pins p1 connected to terminals for supplying power and signals to the circuit board 2a. It is. The male side of the housing M holding these pins p is located inside the resin casing 3, and the female side of the housing M to which an external circuit is connected protrudes outside the resin casing 3.

  One end side of the pin p0 is connected to the GND of the circuit board 2a as described above. The other end of the pin p <b> 0 is a ground connection point E <b> 1 exposed from the inside of the housing M to the lower surface of the housing M located outside the resin housing 3.

  The coating layer 4 coats the resin casing 3 together with the exposed ground connection location E1 on the other end side of the pin p0. Since the ground connection location E1 is a conduction location to the GND of the mounting substrate 2, the resin casing 3 is grounded to the GND.

  As described above, according to the electronic component 1 of the present embodiment, the mounting substrate 2 includes the ground connection location E1 that is not covered by the resin housing 3 and includes a conduction location to GND using a circuit component called the connector 2c. Have. And the coating layer 4 which consists of plating or a conductive coating coats the resin housing | casing 3 for every ground connection location E1, and functions as a noise shield layer. Therefore, noise shielding performance can be reliably obtained with a simple configuration that does not require adding special parts only for connection to GND.

  Next, FIGS. 2A and 2B show a configuration example of the connector 2c. FIG. 2B is a plan view of the connector 2c, and FIG. 2A is a side view of the connector 2c.

  The connector 2c has one pin p0 and one or more pins p1. The pin p0 branches off from a male terminal 21 connected to the GND of the circuit board 2a, a terminal 22 in the housing M that serves as a contact point between the terminal 21 and the female side, and a path connecting the terminal 21 and the terminal 22. Terminal 23 exposed to the outside from the inside of the housing M. The terminal 23 is a terminal to be a ground connection location E1.

  2A and 2B, the pin p0 connects an external circuit and the GND of the circuit board 2a, and therefore functions as a pin for supplying power, signals, etc. to the circuit board 2a. Can do.

  3A and 3B show another configuration example of the connector 2c. FIG. 3B is a plan view of the connector 2c, and FIG. 3A is a side view of the connector 2c.

  The connector 2c has one pin p0 and one or more pins p1. The pin p0 has a male-side terminal 21 connected to the GND of the circuit board 2a and a terminal 23 connected to the terminal 21 and exposed to the outside from within the housing M. The terminal 23 is a terminal to be a ground connection location E1. The connector 2c does not have a terminal serving as a contact point with the female side.

  According to the configuration of FIGS. 3A and 3B, the pin p0 connects the ground connection point E1 to the GND of the substrate circuit 2a, but does not function as a pin for supplying power or signals to the circuit substrate 2a. In this case, a plurality of pins p1 for supplying power and signals to the circuit board 2a may be provided, and one or more of them may be used as pins for connecting the external circuit and the GND of the circuit board 2a.

  In the present embodiment, a plurality of pins p0 may be provided.

[Embodiment 2]
The following will describe another embodiment of the present invention with reference to FIG.

FIG. 4 shows a configuration of the electronic device 11 according to the present embodiment.
The electronic device 11 is an on-vehicle ECU, for example, and includes a mounting substrate 12, a resin casing 13, and a coating layer 14.

  The mounting board 12 has a configuration in which circuit components including one or more circuit elements 12b and a connector 12c are mounted on the circuit board 12a. The resin casing 13 is a hollow package with respect to the mounting substrate 12, and covers, for example, the entire circuit board 12a, the entire circuit elements 12b, and the exposed parts of the circuit components and the circuit board 12a. The male side of the connector 12c is located inside the housing 13 and is connected to the circuit board 12a by pins. The female side of the connector 12c protrudes outside the resin housing 13 and is connected to an external circuit. The coating layer 14 is made of plating or conductive resin, and coats the resin casing 13.

  A part of the resin casing 13 is in contact with the surface of the circuit board 12a, and an opening H1 is formed in the part so that a part of the GND pattern of the circuit board 12a is exposed. The part of the exposed GND pattern serves as a ground connection point E <b> 2 for the coating layer 14. If there is a possibility that the periphery of the opening H1 is not sealed by the resin casing 13, the sealing performance can be secured by connecting the resin casing 13 and the GND pattern with a conductive adhesive or the like.

  The coating layer 14 coats the resin casing 13 together with the ground connection location E2. The coating layer 14 is grounded to GND through the ground connection point E2.

  As described above, according to the electronic component 11 of the present embodiment, the mounting substrate 12 has the ground connection portion E2 that is part of the GND pattern and is not covered with the resin casing 13. And the coating layer 14 which consists of plating or a conductive coating coats the resin housing | casing 13 for every ground connection location E2, and functions as a noise shield layer. Therefore, noise shielding performance can be reliably obtained with a simple configuration that does not require adding special parts only for connection to GND.

[Embodiment 3]
Another embodiment of the present invention will be described with reference to FIG.

FIG. 5 shows a configuration of the electronic device 21 according to the present embodiment.
The electronic device 21 is, for example, an in-vehicle ECU, and includes a mounting substrate 22, a resin casing 23, and a coating layer 24.

  The mounting board 22 has a configuration in which circuit components including one or more circuit elements 22b and a connector 22c are mounted on the circuit board 22a. The resin housing 23 is a package molded directly on the mounting substrate 22. For example, the entire circuit board 22 a, the entire circuit elements 22 b, and the exposed parts of the circuit components and the circuit board 2 a are connected to each other. Covering. The male side of the connector 22c is located inside the housing 23 and is connected to the circuit board 22a by a pin. The female side of the connector 22c protrudes outside the resin housing 23 and is connected to an external circuit. The coating layer 24 is made of plating or conductive resin, and coats the resin casing 23.

  An opening H2 is formed in a part of the resin casing 23 so that a part of the GND pattern of the circuit board 22a is exposed. The exposed portion of the GND pattern becomes a ground connection point E3 for the coating layer 24. When there is a possibility that the periphery of the opening H2 is not sealed by the resin casing 23, the sealing performance can be ensured by connecting the resin casing 23 and the GND pattern with a conductive adhesive or the like.

  The coating layer 24 coats the resin casing 23 together with the ground connection location E3. The coating layer 24 is grounded to GND through the ground connection point E3.

  As described above, according to the electronic device 21 of the present embodiment, the mounting substrate 22 has the ground connection portion E3 that is part of the GND pattern and is not covered with the resin casing 23. And the coating layer 24 which consists of plating or a conductive coating coats the resin housing | casing 23 for every ground connection location E3. Therefore, noise shielding performance can be reliably obtained with a simple configuration that does not require adding special parts only for connection to GND.

  The electronic device of the present invention can be suitably used for, for example, a vehicle-mounted device that wants to shield external noise.

1, 11, 21 Electronic device 2, 12, 22 Mounting board 2c Connector (circuit component)
3, 13, 23 Resin housing 4, 14, 24 Coating layer E1, E2, E3 Ground connection location

Claims (1)

An electronic device,
A mounting substrate, a resin casing as a package for the mounting substrate, and a coating layer made of plating or conductive paint coated on the resin casing,
The mounting board has a ground connection location that is not covered by the resin casing, and includes a conduction location to the ground of the mounting board using circuit components of the mounting board or a ground pattern of the mounting board. And
The electronic device, wherein the coating layer coats the resin casing together with the ground connection portions.

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