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Passive components make the grade

Specifying high reliability electronic components can feel overwhelming at first glance. DMTL walks buyers through the levels.

Commercial grade: Starting with commercial grade, components are manufactured to datasheet specifications only. A large amount of flexibility surrounds the design, materials, processes and testing.

AEC-Q200: Moving to automotive grade, AEC-Q200 is a stress test qualification for passive components, defined by the Automotive Electronics Council (AEC). For a manufacturer to state their passive electronic component is AEC-Q200 qualified, the product must be tested, and the results logged, as outlined in the qualification document, resulting in a grading between Grade 0 to 4. Unless changes are made to either the product or process no further testing is required to supply AEC-Q200 qualified passive electronic components.

COTS-Plus: A COTS-Plus component is designed and manufactured to commercial standards. The production batch is then up-screened, typically with testing in ‘accordance’ to a particular MIL-PRF specification with the ability to specify reliability grading, surge current and group testing where applicable. It may also include known methods specific to the manufacturer resulting in increased reliability.

IECQ-CECC: For IECQ-CECC components, qualification is granted within the IECQ-CECC system when the manufacturer can demonstrate an electronic component or range of components meets the specification. CECC parts can only be sold and released by authorised distributors which the manufacturers appoint. A listing as a franchised source for the manufacturer is not enough to supply CECC released products.

MIL-PRF: For a manufacturer to offer MIL-PRF approved product, it must be listed on the QPL (Qualified Product List), which requires approval of the manufacturer’s QA program and extensive documentation to prove each part will be manufactured identically. Thus, the design is strictly controlled and certain changes must be qualified and submitted to the Defense Logistics Agency for approval. Lot testing is mandatory
for the manufacturer to maintain qualification.

DLA Land and Maritime, DESC and DSCC drawings: Drawings are intended for use when military QPL components are not available or will not adequately perform the required function of the application. They also help reduce document duplication. To list as an approved source against the drawing, it is normally stipulated the manufacturer is listed on the QPL or has agreed on an inspection program to the referenced MIL-PRF and is detailed in the scope of the drawing.

ESCC QPL: European Space Components Coordination, Qualified Parts List makes available space components which have been evaluated, qualified and maintained to the standards used in European member states space programs. This allows passive electronic components to be purchased to a detailed specification. This strictly controls the design, process control, inspection and documentation.

EPPL: The European Preferred Part List provides users with component availability suitable for use in space missions but which are not fully space qualified and do not appear on ESCC QPL.

In summary, as reliability of passive electronic components increases so does cost, while range and availability decreases. This can create major challenges at every stage of the program.

DMTL works with trusted manufacturers who offer products qualified to various levels. The company works with these manufacturers to ensure the correct product is selected and supplied with the necessary paperwork, while also ensuring availability and cost requirements are adhered to throughout the program.

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