Mechanical Load
Mechanical deformation measurements quantify the stress experienced by an integrated circuit package during board assembly and testing. Excessive package strain can crack solder joints and damage the internal silicon die or the wire bonds. This mechanical load occurs when the printed circuit board is bent during operations like panel routing or connector insertion.
It is a critical metric for ensuring that the component does not experience forces beyond its physical limits. Designers monitor these mechanical forces because they can lead to immediate or latent electrical failures in high-density ball grid array packages.
Measurement Protocol
Measurement of this deformation is achieved using strain gauges attached to the board surface near the package corners. These sensors measure the minute expansion and contraction of the board as it is subjected to assembly forces. The collected data is analyzed to ensure that the stress does not exceed JEDEC standards.
Failure Mechanism
Failure occurs when the board undergoes excessive flexing during manufacturing or transport. In-circuit test fixtures use press-down pins that can apply localized forces if the support pins are poorly positioned. By redesigning the test fixture and optimizing the support points, engineers can reduce the strain on sensitive ball grid array packages.
This intervention preserves the structural integrity of the solder joints and avoids premature field failures.
