| 摘要 |
An automotive electronic module (22) including a sealing arrangement having a power transistor (4) attached to a printed circuit board (2); a sealing compound layer (18) encapsulating the transistor; a heat sink (8) contacting the transistor and extending through the sealing compound at a surface of the sealing compound remote from the transistor; and a flange (10) formed of flexible material secured to the heat sink and extending into the sealing compound from beyond the surface. The flange prevents loss of adhesion due to differential thermal expansion between the sealing compound and the heat sink (which could create a path for water ingress) by (i) intercepting the force caused by thermal contraction of the sealing compound, (ii) providing increased surface area for the sealing compound to adhere to, and (iii) re-distributing the thermal contraction force through its flexibility and that of the potting compound and the increased surface area of adhesion. The flange also increases the path that water would have to travel to reach a sensitive area.
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