Selection Approach
PEMs must be traceable to the branded manufacturer. PEMs must be procured from the manufacturer or their approved distributor.4

APL uses a four-step approach to part selection:

  1. concurrent engineering
  2. evaluation of each part for its intended application
  3. partnership with world-class suppliers
  4. review of the manufacturer’s reliability data7

Additional information to consider in PEMs selection are Attributes and Process Flow considerations, as seen in the figures below.

PEMs Procurement Attributes
Process Flow for PEM Use
After source selection and screening is complete, PEMs qualification should take place to yield an acceptable level of confidence in the selected product. If a space/military system requires optimum reliability and if PEMs are part of the implement/mission plan, then PEM qualification is mandatory.

PEMs qualification objectives must be:

  • To test to verify compliance with the performance requirements of the application environment over the intended mission lifetime.
  • To test using practices and facilities with demonstrated capabilities sufficient to handle and test the technologies involved.4
APL utilizes a five-step testing regime:
  1. Radiation hardness assurance
  2. Temperature cycling
  3. Steady-state temperature-humidity bias life test
  4. DPA
  5. High-temperature operating life7