Maxim does not condone up-screening. All Maxim parts are built to the MIL-PRF-38535 recommendations for step coverage and metal migration. However, not all parts have been characterized to work at high (or very low) temperatures and may still experience field failures in up-screened applications. Additionally, up-screening automatically voids the Maxim product warranty. Maxim's military parts, including the ruggedized plastic and V62 devices, are characterized and tested to perform in the stressful military and aerospace environments. Both the design of the chip and the wafer fabrication process are geared to yield a rugged chip. This forms the basis of the devices Maxim offers to our military and aerospace customers. Contact Maxim's Military Business Manager for assistance in selecting suitable parts for a high-reliability application.