Acceleration/shock limit on the chip packaging for military applications

Question: What is the acceleration/shock limit on chip packaging?



On an industrial part we do not spec this parameter and we do not test for this parameter either. This type of test is normally only performed on hermetically sealed packages used with military specifications. Our parts, neither use hermetically sealed packages nor meet military specs. On a hermetically sealed part like a ceramic DIP package, the cavity surrounding the die is open and the bondwires are free to move in response to acceleration and inertia. In the case of a plastic encapsulated part like an SSOP, the plastic mold compound like Sumitomo EME6300H or EME6600H provides an additional structural support for the attachment of the bondwires, that prevents shear movement, and tension or compression is distributed over the whole of the package, not focused at the attachment points of the bondwire. Hence, to our best estimation the wirebonds should withstand breakage due to acceleration virtually to the destruction point of the package. As a point of reference, our internal qualification specifications on SSOP for ball shear and wire pull are 14 gm minimum and 4 gm minimum respectively. Our typical ball shear ranged from 26.75gm to 39.43gm on SSOP48, and our typical wire pull ranged from 6.12mil to 7.43mil on SSOP48. On PDIP28 ball shear ranged from 33.5gm to 44.0gm and wire pull from 7.8gm to 14.6gm. These tests were performed in open air on unencapsulated parts and are the closest equivalent data we have to what your customer is asking. We anticipate that the encapsulated values for these same parameters would be orders of magnitude higher.