Patent Application
20200196433
This application claims priority to French Application No. 1872865, filed on Dec. 13, 2018, which application is hereby incorporated herein by reference.
The present disclosure relates generally to a method for mounting electronic components, e.g., on a circuit board.
The mounting of electronic components on a circuit board can be realized in several different ways. One of these ways consists in directly soldering the contact(s) of the electronic component on the connection pads of the circuit board.
It would desirable to be able to at least partially improve certain aspects of the known methods for mounting components on a circuit board.
The present disclosure relates generally to a method for mounting electronic components on a circuit board. Particular embodiments relate to a method for mounting discrete components on a circuit board.
One embodiment provides a method comprising a step of gluing a discrete component on a circuit board with a first glue the composition of which is such that it interacts electrically neither with a second glue used for attaching a cap to the circuit board, nor with a third glue used for attaching one or more integrated circuits to the circuit board.
According to an embodiment, the first glue is an insulating glue.
According to an embodiment, the second glue is an insulating glue.
According to an embodiment, the first glue is identical to the second glue.
According to an embodiment, the third glue is an insulating glue.
According to an embodiment, the first glue is identical to the third glue.
According to an embodiment, the method further comprises a step of gluing the cap with the second glue on the circuit board.
According to an embodiment, the discrete component is a passive component.
According to an embodiment, the discrete component is a component comprising at least two contacts accessible from an upper face.
According to an embodiment, the second glue is an epoxy-type polyepoxide-based glue.
According to an embodiment, the third glue is an epoxy-type polyepoxide-based glue.
According to an embodiment, the discrete component is a surface-mount component.
According to an embodiment, the discrete component is a passive component.
A further embodiment provides the electronic circuit in which at least one discrete component is glued on a circuit board with a first glue the composition of which is such that it does not interact with a second glue used for attaching a cap to the circuit board and with a third glue used for attaching one or more integrated circuits to the circuit board.
The foregoing features and advantages, as well as others, will be described in detail in the following description of specific embodiments given by way of illustration and not limitation with reference to the accompanying drawings, in which:
Like features have been designated by like references in the various figures. In particular, the structural and/or functional features that are common among the various embodiments may have the same references and may have identical structural, dimensional and material properties.
For the sake of clarity, only the operations and elements that are useful for an understanding of the embodiments described herein have been illustrated and described in detail.
Unless specified otherwise, when reference is made to two elements that are connected to each other, this means directly connected without any intermediate elements other than conductors, and when reference is made to two elements that are linked or coupled to each other, this means that these two elements can be connected or be linked or coupled by way of one or more other elements.
In the following disclosure, unless indicated otherwise, when reference is made to absolute positional qualifiers, such as the terms “front”, “back”, “top”, “bottom”, “left”, “right”, etc., or to relative positional qualifiers, such as the terms “above”, “below”, “higher”, “lower”, etc., or to qualifiers of orientation, such as “horizontal”, “vertical”, etc., reference is made to the orientation shown in the figures.
Unless specified otherwise, the expressions “around”, “approximately”, “substantially” and “in the order of” signify within 10%, and preferably within 5%.
The circuit 10 is composed of a circuit board 11 on which electronic components are mounted. More particularly, the circuit board 11 comprises on its upper face and/or its lower face electronic components, e.g., one or more integrated circuits 12 (two integrated circuits are illustrated in
The circuit 10 is, moreover, generally covered by a protective cap (not shown in
According to an alternative embodiment, it would be possible for the circuit not to be covered by a cap, but rather exhibit, in lieu of the layer of glue 17, a layer of epoxy resin surrounding and covering the components of the circuit 10.
The contacts 15 of the integrated circuits 12 are, for example, arranged on an upper face and/or a lower face of the latter. The contacts 15 arranged on the lower surface are, for example, soldered directly to the connecting terminals of the circuit board (see
According to an embodiment, the discrete components 14 are glued directly on the circuit board 11 by means of a layer of glue 19. The glue 19 is a glue that does not interact electrically with the glues 17 and 18. In other words, when the glues 17 and/or 18 are insulating, the glue 19 is an insulating glue that can be in contact with the glues 17 and 18, and when the glues 17 and/or 18 are conductive glues, the glue 19 cannot be in contact with the glues 17 and/or 18. More specifically, the glue 19 is an insulating glue, e.g. an insulating epoxy-type glue. According to an embodiment, the glue 19 can be the same glue as the glue 17, or 18, provided that it is insulating, and, in this case, a discrete component 14 can be glued on the circuit board 11 with the same layer of glue as the integrated circuit 12. The contacts 15 of the components 14 are connected to other contacts by a wire bonding method. In
One method for manufacturing the circuit 10 is the following. The components 12 and 14 are glued on the circuit board by way of the layers of glue 18 and 19. Several components 12, or 14, can be glued by way of the same layer of glue. The connections necessary for the operation of the circuit 10 are realized, for example, by using a wire bonding method. Once the circuit 10 is operational, a protective cap can be glued on the circuit board 11 by way of the layer of glue 17 which is formed on the outer edge of the circuit board 11.
One advantage of gluing discrete components 14 on the circuit board 11 is that it makes it possible to place a discrete component 14 closer to an integrated circuit 12 on a circuit board. Indeed, the discrete components are generally soldered to connection pads of a circuit board. A disadvantage of soldering is that it forces certain design rules to be observed so as to avoid the solder touching the layer(s) of glue used to attach other components to the circuit board and/or used to attach the cap on the perimeter region of the circuit board. Avoiding the use of solder thus makes it possible to reduce design constraints and thus to increase the number of components per circuit board or else to reduce the surface of the latter.
A preferred example of a way of connecting two contacts 15-inf of two different integrated circuits 12 is the following. Each contact 15-inf is connected, for example by soldering or brazing, to an end of a via 25 that traverses the circuit board 11. The integrated circuit 12 is, in this case, glued to the circuit board 11 with a layer of the glue 18 arranged between the integrated circuit 12 and the board 11. In the case where the integrated circuit 12 comprises a plurality of contacts 15-inf, the glue 18 is insulating so as to avoid short-circuiting the contacts 15-inf between each other. Moreover, the layer of the glue 18 can, for example, comprise openings at the connections of the contacts 15-inf.
Another example of a way of connecting (not shown) contacts 15-inf of several different integrated circuits is the following. In the case where the contacts 15-inf are coupled to a same terminal or to a same potential, e.g. the ground, the glue 18 can be electrically conductive. The layer of glue 18 thus acts as a conductor.
A preferred example of a way of connecting a contact 15 of a discrete component 14 to a contact 15-sup of the integrated circuit 12 is the following. The two contacts are connected by a wire bonding method. A wire bonding method is a method in which a contact is connected to another by a bondwire. More precisely, a first end of the bondwire is bonded to a first contact then the second end of the bondwire is bonded to a second contact.
The discrete component 40 is of the same type as the component 14 described in relation to
The component 40 is mounted on a circuit board 60 of the same type as the circuit board 11 described in relation to
The contacts 42 are each connected to another contact (not illustrated in
Various embodiments and variants have been described. Those skilled in the art will understand that certain features of these different embodiments can be combined and other variants will readily occur to those skilled in the art. In particular, only discrete components comprising two contacts have been described, but these embodiments also apply to discrete components comprising more than two contacts, such as, for example, a transistor.
Finally, the practical implementation of the embodiments and variants described herein is within the capabilities of those skilled in the art based on the functional description provided above.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1872865 | Dec 2018 | FR | national |
