WO2012126748A1

WO2012126748A1 - Electronic device with a substrate in an insert housing

Info

Publication number: WO2012126748A1
Application number: PCT/EP2012/054147
Authority: WO
Inventors: Andreas Otto; Rainer Holz
Original assignee: Robert Bosch Gmbh
Priority date: 2011-03-22
Filing date: 2012-03-09
Publication date: 2012-09-27
Also published as: BR112013023980A2; CN107852837A; DE102011005890A1; EP2689646A1

Abstract

The invention relates to an electronic circuit arrangement (102) with a substrate (106) and a module (108) to be received in an insert housing (104). An electronic circuit arrangement (102) according to the invention comprises at least one spring element (116, 118) in addition to the substrate (106) and the electronic module (108) that is held by the substrate (106). The circuit arrangement (102) is provided for inserting into a housing (104). The module (108) thermally contacts a housing region (110, 136) in order to dissipate heat after the insertion, and the contact is made via the at least one spring element (116, 118). The circuit arrangement also comprises at least one spacer (126, 128) on the module or on the housing (108) in order to prevent damage during the insertion of the circuit arrangement (102) into the housing (104).

Description

Description title

PRIOR ART The invention relates to an electronic circuit arrangement with circuit carrier and module for receiving in a plug-in housing.

For electronic devices in which electronic circuits are arranged in a housing, different housing concepts are known, which are to be evaluated in the individual case from the viewpoint of space, cost and cooling of the electronic components. For electronic devices such as control devices in the

Automotive sector is the arrangement in a housing according to the tub-lid principle, the use of an extruded profile as a housing, or the direct encapsulation of the electronic circuit arrangement known.

In this case, designed according to the tub-lid principle electronic devices often optimum cooling options. The cooling of the components carried by a circuit carrier, such as a printed circuit board, generally takes place through the printed circuit board and onto cooling elements of the housing. However, the cost or space-related aspects tend to be more difficult to optimize in this concept.

The use of an extruded profile for the housing is usually less expensive, but problems in cooling and miniaturization can occur here. Since the profile is closed at one end, here possible space and

Loss of cooling potential lost. As a rule, only peripheral areas of the housing are available for cooling in this concept.

The direct encapsulation of a circuit board most likely supports miniaturization and has the greatest cost saving potential. However, the size of the to be overmoulded Circuit carrier limited. Therefore, this technique can only be used for comparatively small electronic devices.

From DE 102 97 047 B4 an electronic component arrangement is known, in which a chip with spring-formed terminals mounted on a frame on a circuit board and then brought into direct contact with a heat sink. Of the

Heatsink can serve to hold the chip in the mounted position, so that the resilient terminals press the chip against the heat sink. From DE 196 04 124 A1 an electrical device is known in which a

Power component is pressed by spring means to a heat-dissipating housing part. Thus, by the thermal contacting a cooling of the device through the housing can be done.

In these approaches, a cooling over the classic concepts is improved, however, a use together with in itself cost extruded profiles is not possible, because in this case the circuit is inserted into the housing; but to avoid damage must be a direct contact between

Entwärmenden modules / components and housing can be avoided.

Disclosure of the invention

According to the invention, an electronic circuit arrangement with a circuit carrier, an electronic module held by the circuit carrier and at least one spring element are proposed. The circuit arrangement is provided for insertion into a housing. For cooling, the module contacts after insertion

Housing area thermal. The contacting is accomplished via a spring element. There is provided a fastening means. The circuit carrier, for example, as a printed circuit board or PCB ("Printed Circuit Board") and / or other, even three-dimensional structure for holding circuits,

Components, etc. may be formed. The module may also include a printed circuit board or similar support structure, and / or may include one or more electronic components, including electronic circuits (ICs), circuit elements such as capacitors or resistors, control elements such as Transistors, etc. include. Such a device may either itself be a device to be heat-treated and / or may carry a device to be heat-treated.

The fastening means preferably comprises at least one spacer and / or at least one locking element. The fastening means can be provided at any points on the circuit arrangement. Preferably, the attachment means is configured so that the circuitry can be mounted in a housing. The fastening means on the circuit arrangement can be complementary to the

Fixing means to be designed on a housing into which the circuit arrangement is to be inserted. Furthermore, a complementarily designed

Fastening means of the circuit arrangement and a housing, the position of the

Circuit arrangement in a housing fixed. Complementary in the sense of the invention means that for the fastening means to the circuit arrangement, a matching counterpart is provided on a housing, in which the circuit arrangement

can be inserted. For example, for a spacer on the

Circuitry a locking element provided on a housing to secure the circuit arrangement when inserted into a housing in a desired position. The at least one spacer can be galvanically built up on the module

Element include, such as a ball, hemisphere or other, raised element. Additionally or alternatively, the module may be equipped with a pre-formed element as a spacer. This component may be, for example, a ball, a rivet, a press-in pin, and / or a stamped grid.

The at least one spacer may include floating points, sliding lines or sliding surfaces, and may include, for example, three or more sliding points.

The at least one locking element can serve for locking the circuit arrangement to be inserted in an end position in a housing. The

Locking element may for example comprise one or more latching points. A latching point on the circuit arrangement may be provided for the engagement of a spacer on a housing. The spring element can serve in the inserted state for defining the distance between circuit carrier and module. Alternatively, the module can also be held directly or rigidly by the circuit carrier. The at least one spring element can be the electrical contact of the

Circuit carrier serve. Additionally or alternatively, this or another

Serve spring element of the electrical contacting of the module. For example, at least one spring element can be provided for the electrical contacting of circuit carrier and module with one another. In a particular variant of this

Embodiments, at least one spring element is formed from an outgoing from the circuit board electrical conductor.

The electrical conductor can be, for example, a copper track led out of the circuit carrier (such as a printed circuit board), which is used for electrical purposes

Contacting the circuit substrate is provided. This electrical conductor can be electrically connected, for example, by means of plated-through holes with conductor tracks or further electrical conductors of the circuit carrier.

The led out of the circuit board contacting can be formed, for example, in a separate processing step to a spring element, in particular be formed. This leaf springs, all types of compression springs, torsion springs, bending springs or similar spring elements can be formed.

An electronic circuit arrangement with at least one spring element led out of the circuit carrier can also be independent of those described here

Spacers or locking elements are present. Such a circuit arrangement, for example, for inclusion in a according to the tub-lid principle

be constructed housing provided. Furthermore, a corresponding electronic device can be provided.

The invention further proposes a housing for receiving one of the electronic circuit arrangements outlined here. The housing includes a

Fastening means for locking the circuit to be inserted in an end position in the housing. The fastening means preferably comprises at least one spacer and / or at least one locking element. The attachment means may be provided at any location on the housing. Preferably, the fastening means is designed so that the housing receives a circuit arrangement. The fastener on the

Housing may be designed to be complementary to the fastening means on a circuit arrangement which is to be received in the housing. Continue to enter

complementary configured fastener of the housing and a

Circuitry the position of a circuit arrangement in the housing firmly.

Complementary in the sense of the invention means that for the fastening means the housing is provided a matching counterpart to a circuit arrangement which is to be received in the housing. Thus, for example, a locking element is provided on a circuit arrangement for a spacer on the housing in order to fasten a circuit arrangement when inserted into the housing in a desired position.

The at least one spacer may comprise an element galvanically mounted on the housing, such as a ball, hemisphere or other raised element. Additionally or alternatively, the housing may be equipped with a pre-formed element as a spacer. This component may be, for example, a ball, a rivet, a press-in pin, and / or a stamped grid.

The at least one spacer may include floating points, sliding lines or sliding surfaces, and may include, for example, three or more sliding points. The at least one locking element can be used to lock a

Circuit arrangement serve in an end position in the housing. The locking element may for example comprise one or more latching points. A locking point on the housing may be provided for the engagement of a spacer on a circuit arrangement. The housing may comprise approximately an extruded profile. Alternatively, it is also possible to use profiles which are produced by means of other shaping methods, such as e.g. Deep drawing are made. Additionally or alternatively, the housing may be constructed according to the tub-lid principle.

According to the invention, an electronic device is furthermore proposed which comprises one of the electronic circuit arrangements sketched here and a housing into which the Circuit arrangement is inserted, wherein a fastening means on the circuit arrangement is designed to be complementary to a fastening means on the housing. The housing and the circuit arrangement may be formed as outlined above, wherein the circuit arrangement is locked in the housing.

Advantages of the invention

With the invention, a direct contact between module to be Entwärmendem and housing can also be established if an extruded profile or other housing is used, in which the circuit arrangement is inserted. By providing spacers, the electronics (i.e., the module or modules to be heat-treated

Components, but also other components) as well as the housing (in particular the intended for the thermal contacting of the module areas) are protected from damage.

By means of the invention, the lossy power electronics can be applied directly to cooling surfaces of the housing, so as to realize optimal heat dissipation. An approximately existing gap between the Entwärmungsflächen of the module and the housing can by at least a partial use of a corresponding

Wärmeleitmediums be reduced.

The invention thus extends the capabilities of a housing concept based on extruded profiles or on profiles made by similar processes (e.g., deep drawing). The advantages resulting from this concept, in particular also cost advantages, can be used for electronic devices, but compared to the conventional concept, the cooling can be optimized because a direct cooling of modules / components is possible through the housing. The invention enables the development of optimized cooling concepts based on, for example, slug-up cooling, modular partitioning and suitable intermodule connection techniques.

Optimized cooling concepts based on the invention make it possible, for example, to use cost-effective extruded profiles or other plug-in housings not only for logic modules but also for power modules. The thermal / mechanical contact between the component to be heated and the housing can over the desired life of the device by the

Spring element can be held with a correspondingly adapted spring constant. The

Spring element allows safe contact, for example, with expansions or other movements of the housing, the module, or the circuit substrate, as may occur for example in temperature changes or shocks, e.g. at a

Control unit in the vehicle area.

Are spring elements between circuit carrier and too Entwärmendem

Module / component provided, a two-sided assembly of the module is possible.

If spring elements are provided between the circuit carrier and the housing, the circuit carrier, for example a base circuit board, can be equipped on two sides. In all these cases, additional space can be gained for equipping. Optimized cooling concepts based on the invention also enable a further miniaturization of the (power) electronics installed in the electronic device.

The use of the spacers and / or locking elements according to the invention for locking the circuit arrangement to be inserted in the plug-in housing allows a simple fixation of the complete system. The fixation becomes the optimal one

Entwärmungspfad made and by means of the provided spring elements on the

Lifetime of the device secured. The spacers protect the electronics as well as the heat dissipation surfaces of the module and the housing from assembly damage. The spacers, for example, sliding points and / or lines can additionally be formed as a guide element for guiding the electronic circuit arrangement when inserted into the housing.

Brief Description of the Drawings Further aspects and advantages of the invention will now be described more fully with reference to the accompanying drawings. FIG. 1 shows a section through an exemplary embodiment of an electronic device according to the invention; FIG. characters

2A, 2B are schematic sectional views through a circuit carrier of a

inventive electronic circuit arrangement with led out of an inner layer spring elements; and

3 shows a section through a further embodiment of a

inventive electronic device.

Embodiments of the invention

1 shows in the form of a schematic sectional view of an embodiment 100 of an electronic device according to the invention with an electronic circuit arrangement 102 which is accommodated in a plug-in housing 104, but is not yet in a locked end position.

The circuit arrangement 102 includes a circuit board as a circuit board 106 and a module 108. Of the designed as an extruded housing 104 a top 1 10 and a bottom 1 12 are indicated. The printed circuit board 106 carries on its side facing the module 108 elements of which a component 1 14 and spring elements 1 16, 1 18 are shown. The spring elements 1 16, 1 18 serve for the spaced positioning of the module 108 and for electrical contacting of printed circuit board 106 and module 108. The module 108 is at its the

Printed circuit board 106 side facing electronic components 120, 122 equipped. On its side facing the housing 104, 110, the module 108 is provided with a thermal contacting element 124 as well as with spacers, of which sliding points 126, 128 are shown.

It is believed that for at least one of the devices 120, 122, for example, at least the element 122, cooling is required, such as because it is a lossy device. The components 120, 122 are insulated via a printed circuit board 130 of the module 108 and the contacting element 124 to the top 1 10 of the housing 104. For efficient thermal diffusion, the housing top 1 10 is provided with cooling fins 132. In the (not shown here) fully inserted and locked state of the electronic circuitry 102 in the housing 104 is the Module 108 with its contacting element 124 by means of the force exerted by the spring elements 1 16, 1 18 spring force to the top 1 10 of the housing pressed. A thermal compound which is possibly required for optimum thermal contacting or a comparable thermally conductive medium is not shown in FIG. 1 for reasons of clarity.

The circuit arrangement 102 is inserted into the housing 104 in the direction indicated by the arrow 134. In this case, the circuit board 106 slides over the bottom 1 12 of the housing 104, while the sliding points 126 and 128 along the inner surface 136 of the top 10 of the housing 104 slide. As can be seen from FIG. 1, the sliding points 126, 128 are raised above the thermal contact 124 and optionally further components present on the upper side of the base circuit board 130 of the module 108, so that only the sliding points 126, 128 engage mechanically when the arrangement 102 is inserted with the inner surface 136 of the housing top 1 10 stand. In this way, upon insertion, damage to the structures on the circuit board 130, e.g. the thermal contacting element 124 (more generally the Entwärmungsfläche of the module 108), but also the inner surface 136 of the top 1 10 of the housing 104 avoided. Also, an optionally on the top of the element 124 or the inner surface 136 of the housing top 1 10 previously applied heat transfer medium is not abraded or impaired in any other way.

The sliding points 126, 128 are formed in the example of Figure 1 as balls that are either populated as a prefabricated components on top of the base circuit board 130 of the module 108, or are built up galvanically on the circuit board 130. Other embodiments of the sliding points 126, 128 are also conceivable, for example in the form of

Hemispheres or pyramids; In addition to floating points, others can be more general

Variants of spacers are used, such as sliding surfaces such as

For example, the surfaces of rivets or Einpresspins, or sliding lines or lines such as the surface of a stamped grid.

The balls 126, 128 shown in FIG. 1 can be produced, for example, in a standard SMD ("Surface Mounted Device") process, for example via a balling method. For this purpose, neither special machines nor screwing or riveting processes are required. Thus, in principle, the complete module 108 can be manufactured in a standard SMT ("Surface Mounted Technology") process. On the inner surface 136 of the upper side 1 10 of the housing 104 latching points or recesses 138, 140 are prepared as detents. When inserting the arrangement 102, the ball 126 reaches the position of the latching point 138 and the ball 128, the position of the latching point 140. Mediated by the force exerted by the elements 1 16, 1 18 spring force the module 108 engages with the balls 126, 128 in one the latching points 138, 140 predetermined position in the interior of the housing 104 a. The circuit arrangement 102 remains fixed in the housing 104, as long as the spring elements 1 16, 1 18 exert a sufficient spring force, which must be designed accordingly for a certain life of the device 100.

While only two sliding points 126, 128 are indicated in FIG. 1, it is advantageous in the exclusive use of sliding points as spacers to provide in particular at least three sliding points on the side of the module facing the housing, in order to be able to insert the module optimally, without components as the thermal contacting or Entwärmungselement 124, a thermal paste, or the inner surface 136 of the top 1 10 to damage. In this case, the at least three sliding points should preferably not be located on a line parallel to the insertion direction 134. On the inner surface 136 of the housing, a corresponding number Einrastpunkte can be provided. To have a simple, reliable and correct

To ensure insertion and locking of the arrangement, the number of

Spacers or latching points are not too big. For a use of

Sliding lines or surfaces and the combination of floating points, lines and surfaces applies mutatis mutandis.

After snapping exists between the Entwärmungskomponente 124 and the

Inner surface 136 of the housing 104 only a minimum distance 142, which may be filled by a heat transfer medium. The heat-conducting medium does not have to cover the entire contact surface of the contacting element 124; it is sufficient that the medium is partially present at least where a thermal contact must be optimized for a heat dissipation of a device. Required by the components 120, 122 so for example. In particular, the element 122 an efficient Entwärmungspfad, so must a

Heat transfer medium for bridging the remaining gap 142 in particular be applied over the device 122 on the surface of the contacting element 124. The spacing of printed circuit board 106 and module 108 maintained by the spring elements 16, 18 enables loading of both the upper surface of the printed circuit board 106 and the lower surface of the printed circuit board 130 of the module 108 (ie, two-sided mounting of the module 108). This allows for a suitable partitioning of the components to be accommodated, a minimization of the design of the device 100.

The module 108 may be processed in a standard SMD process in which, for example, first a solder paste pressure is applied to the circuit board 130, then a loading of the module, and then a soldering. The spring contacts 1 16, 1 18 can be attached to the module 108 as prefabricated components during the manufacturing process of the module 108. For the spring elements 116, 118, finished springs could be used, as shown in FIG. for the element 1 18 a C-spring and for the element 1 16 an S-spring. Also coil springs and the like spring designs more can be fitted to the module 108 and soldered. If such springs are used, which are standard components, falls a special or additional

Production costs are not due to this. There are a variety of different springs known as such, so there is a great deal of flexibility in geometry and material with respect to the specific requirements for each application. An electrical contact of the module 108 can via at least one of

Spring elements 1 16, 1 18 done. In this case, additional connection points for electrical contacting between module 108 and base circuit board 106 can be omitted.

Serves one or more of the spring elements 1 16, 1 18 of the electrical contact, can be used as material e.g. Spring bronze can be used. For a long-lasting, reliable

Contact pressure is preferable to the use of spring steel. For a plurality of springs, these can be fitted individually depending on the requirements; in the example of FIG. 1, for example, spring 1 16 could be made of spring bronze for electrical contacting, while spring element 18 is not required for electrical contacting and can reliably produce a spring force over the desired service life of device 100, for example, spring steel. Thus, too

Controllers for more robust applications such as being optimized in a vehicle. In the Fign. 2A, 2B, an embodiment of a module 200 according to the invention is shown. A base circuit board holding the module 200 as well as other elements such as spacers or a housing for accommodating a circuit arrangement consisting of module 200 and base circuit board have been omitted for reasons of clarity.

An electrical conductor 204, for example a copper track, serves the electrical

Contacting the module 200 and runs between external or led out

Contact surfaces 210 through the interior of the module circuit board 202. About a

Through-hole 206, the conductor 204 is electrically connected to further conductor tracks 208 of the module 200. Figures 2A and 2B illustrate a state before and after a process step for processing the module 200, in which the external

Terminals 210 are processed (for example, bent or deformed), so that areas 212 of the conductor 204 can be used as spring elements. The areas 212 are thus comparable after processing to the spring elements 1 16, 1 18 of the embodiment 100 of Figure 1 and can space the module 200 of a base printed circuit board and at the same time press for heat dissipation to an inner surface of a housing side.

While in the example of FIG. 2B, the regions 212 represent C-springs, in principle any resilient design form can be produced, for example an S-shape or even a simple leaf spring (the latter being sufficient for this purpose on the base printed circuit board or in the electronic device) Space is available). Is used as a housing

Extruded used, are on the top 214 of the module 200 spacers such as the sliding points 126, 128 shown in Figure 1 advantageous. When using a

Housing according to the tub-lid principle may also be a plurality of

Spacers are provided against, for example, provided in a lid latching positions, or it is dispensed spacers and / or locking.

FIG. 3 shows an alternative sectional view in the form of a schematic sectional view

Embodiment 100 of an electronic device according to the invention with a

electronic circuit arrangement 102 which is accommodated in a plug-in housing 104, but is not yet in a locked end position.

The embodiment shown in Figure 3 corresponds to the embodiment of Figure 1. In contrast to Figure 1 is a further embodiment of the fastening means in Figure 3 126, 128, 138, 140 are shown on the slide-in housing 104 and the circuit arrangement 102.

The circuit arrangement 102 includes a circuit board as a circuit board 106 and a module 108. Of the designed as an extruded housing 104 a top 1 10 and a bottom 1 12 are indicated. The circuit arrangement 102 is inserted into the housing 104 in the direction indicated by the arrow 134. In this case, the circuit board 106 slides over the bottom 1 12 of the housing 104, while the sliding points 126 and 128 along the inner surface 136 of the top 10 of the housing 104 slide.

In contrast to Figure 1, the fastening means 138, 140 at the

Circuit arrangement 102 formed by two locking elements 138, 140. These locking elements 138, 140 are on the side facing the housing

Printed circuit board 130 of the module 108 and are designed as latching points or recesses 138, 140. As counterparts to the locking elements 138, 140 on the

Module 108, the fastening means 126, 128 realized on the housing by two spacers 126, 128. These are raised as sliding points 126, 128 via the thermal contact 124 and optionally further, on the top of the base circuit board 130 of the module 108 components so that when inserting the assembly 102, only the sliding points 126, 128 in mechanical engagement with the circuit board 130 of Module 108 stand. In this way, upon insertion, damage to the structures on the circuit board 130, e.g. the thermal contacting element 124 (more generally the Entwärmungsfläche of the module 108), but also the inner surface 136 of the top 1 10 of the housing 104 avoided. Also, an optionally on the top of the element 124 or the inner surface 136 of the housing top 1 10 previously applied heat transfer medium is not abraded or impaired in any other way.

When inserting the arrangement 102, the locking point 138 reaches the position of the ball 126 and the locking point 140, the position of the ball 128. Mediated by the force exerted by the elements 1 16, 1 18 spring force engages the module 108 with the locking points 138, 140 in one the balls 126, 128 predetermined position in the interior of the housing 104 a. The circuit arrangement 102 remains fixed in the housing 104 as long as the

Spring elements 1 16, 1 18 exert a sufficient spring force, which must be designed accordingly for a certain life of the device 100. The invention is not limited to the embodiments described herein and the aspects highlighted therein; Rather, within the scope given by the appended claims a variety of modifications are possible, which are within the scope of expert action.

Claims

claims

1 . Electronic circuit arrangement (102), with

a circuit carrier (106);

- One of the circuit carrier (106) held electronic module (108);

- At least one spring element (1 16, 1 18), wherein the circuit arrangement (102) for insertion into a housing (104) is provided, the module (108) after insertion a housing portion (1 10, 136) for heat dissipation thermally

contacted, and the contact via the at least one spring element (1 16, 1 18) is accomplished; and

- A fastening means (126, 128, 138, 140).

2. A circuit arrangement according to claim 1, wherein the fastening means (126, 128, 138, 140) at least one spacer (126, 128) and / or at least one

Locking element (138, 140).

3. Circuit arrangement according to one of claims 1 or 2, wherein the at least one spacer (126, 128) comprises a on the module (108) galvanically constructed ball.

4. Circuit arrangement according to one of claims 1 to 3, wherein the module (108) is equipped with at least one component in the form of a ball, a rivet, a press-fit pin, and / or a punched grid for forming the at least one spacer (126, 128) ,

5. Circuit arrangement according to one of the preceding claims, wherein the

at least one spacer (126, 128) comprises three or more sliding points.

6. Circuit arrangement according to claim 1 or 2, wherein the locking element (138, 140) comprises one or more latching points (138, 140).

7. Circuit arrangement according to one of the preceding claims, wherein at least one spring element (1 16, 1 18) of the electrical contacting of the circuit substrate (106) and / or module (108) is used.

Circuit arrangement according to claim 7, wherein at least one spring element (212) ί one of the module (200) led out electrical conductor (204) is formed.

A housing (104) for accommodating electronic circuitry (102) according to any one of the preceding claims, including attachment means (126, 128, 138, 140) for locking the circuit assembly (102) to be inserted in an end position in the housing (104).

10. Housing according to claim 9, wherein the fastening element (126, 128, 138, 140) is designed according to one of claims 2 to 6.

1 1. A housing according to claim 9 or 10, wherein the housing (104) comprises an extruded profile.

An electronic device (100) comprising an electronic circuit arrangement (102) according to any one of claims 1 to 8 and a housing (104) into which the circuit arrangement (102) is inserted, wherein a fastening means (126, 128, 138, 140) to the

Circuit arrangement (102) complementary to a fastening means (126, 128, 138, 140) on the housing (104) is configured.

The electronic device of claim 12, wherein the housing (104) of any one of claims 9 to 11 is formed and the circuitry (102) is locked in the housing (104).