Removal of high stress zones in electronic assemblies
AssigneeSafran Electronics & Defense
InventorsPhilippe Chocteau, Denis Lecordier
Life of this patent
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Abstract
The invention relates to an electronic board (1) comprising: —a printed circuit (2) having a connection face (3) defining a plane (X, Y) comprising at least one transfer area (4), —an electronic component (5) comprising at least one contact terminal (6), each contact terminal (6) being brazed or sintered on an associated transfer area (4) by means of a brazing joint or of a sintering joint (7), the electronic board being characterised in that an orthogonal projection of the contact terminal (6) of the electronic component (5) on the connection face (3) of the printed circuit does not overlap the associated area (4).
Claims11
An electronic board comprising:
- a printed circuit having a connection face defining a plane including two, the two pads being separated by a first distance when the electronic board is at ambient temperature, and
- an electronic component including two terminal, each terminal being soldered or sintered on an associated pad of the two pads by means of a solder or sintering joint, the two terminals being separated by a second distance when the electronic board is at ambient temperature,
- wherein the printed circuit having a first thermal expansion coefficient (CTEPCB) in the plane, the electronic component has a second thermal expansion coefficient (CTESMC) in the plane and the solder joint having a third thermal expansion coefficient (CTEJ) in the plane, and
- wherein the first distance (LPCB) is substantially equal to a quotient of a difference between the first thermal expansion coefficient (CTESMC) and the third thermal expansion coefficient (CTEJ) and of a difference between the second thermal expansion coefficient (CTEPCB) and the third thermal expansion coefficient (CTEJ), all multiplied by the second distance (LCMS):
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- so that orthogonal projections of the two terminals of the electronic component on the connection face of the printed circuit do not overlap the associated pads of the two pads.
Dependencies are inferred from the claim text.