BS/EN 16602-70-12-2016 pdf download.Space product assurance Design rules for printed circuit boards.
4.1 Qualified PCBs
Qualified PCBs for space application meet the following conditions:
b. L’C13 is procured in conformance with requirements of ECSS-Q-ST-70-1 1,
c. PCB is procured from a PCB manufacturer that is qualified in conformance with requirements of ECSS-Q-ST-70-1O,
d. the PCB technology is qualified in conformance with requirements of ECSS-Q-ST-70-1O for that PCB manufacturer.
e. the PCB design is in conformance with the requirements of ECSS-Q-ST70-12, and
f. the l’CB design, the manufacturing process and materials are in conformance with the PID of the PCB manufacturer.
PA requirements of space projects use this European Standard as applicable document. Based on their heritage, suppliers can propose the re-use of existing PCB designs that are ‘recurrent” and that are not in compliance with all design requirements of this European Standard. The possible acceptability of those cases is reviewed by the project on case by case basis. The I’CB design is “recurrent” only when no changes are made in the artwork, routing, lay-out, build-up, material selection.
4.2 Manufacturing tolerances
Dimensional measurements of PCBs are “as-designed” except when explicitly mentioned “as-manufactured”.
Design values are affected by the manufacturing tolerances. The minimum value on the PCB as-manufactured equals the design value subtracted with the manufacturing tolerance. See definition of terms in Subdause 3.2.
4.3 Reliability of design
Specific design features of PCBs are recorded as Review Items in the PCH definition dossier. This is done when the design features include a higher technological complexity that can ailed manulacturability or (thermal) reliability. These design features are specifically evaluated by qualification prior to inclusion in the PID.
Requirements in this European Standard generally state minimum dimensions permitted. It is good practice to use minimum dimensions only when necessary to achieve the desired functionality and to design with margin when possible. For instance, it is recommended to implement minimum insulation distance between tracks only when space limitations prevent larger insulation distance. It is recommended to implement fan out of tracks which allows for larger insulation distances where more space is available.
The robustness of the I’CB can be affected when combining multiple design features at the limit of the requirement or recorded as Review Item. The I’CB manufacturer and the supplier evaluate this risk during the design review and provide formal approval during the MRR. The reliability of the manufactured PCB is evaluated by inspection on representative coupons.
5.1 Overview
This clause specifies the iterative process of designing a PCB in collaboration with the PCB manufacturer and specifies associated documentation for the formal authorization for manufacture.
5.2 Documentation
a. The supplier shall issue the PCB definition dossier in conformance with the DRD in Annex A.
b. The supplier shall list design features as Review Items in conformance with Subclause A.2.lc7 from the DRD of the Annex A.
c. The supplier may list other design features as Review Items.
d. The supplier shall submit the PCB definition dossier to the PCH manufacturer for the design review.
e. The supplier should submit to the PCB manufacturer the draft PCB definition dossier or a list of specific Review Items specified in the requirement 5.2b in the design phase, when those Review Items are at the limit of the PID capability.
NOTE Examples of Review Items that can be on the limit of PID capability are: dimensions, number of layers, maximum aspect ratio, number of sequences, material selection or a combination of these. Consultation with PCL3 manufacturer at this early design stage is recommended to avoid unnecessary risks. Multiple iterations can be performed to achieve an agreed PCB definition dossier.
f. The I’CB manufacturer shall review the PCB definition dossier including Review Items for compliance with the ND.
g. As a result of the design review, the PCB manufacturer may identify to the supplier additional Review Items in the PCI3 definition dossier.
NOTE Review Items can exist for PCB designs even
within the capability of the ND. These Review
Items and methods to mitigate them are specified in this European Standard as best
practices and recommendations.
h. The PCB manufacturer shall provide the PCB manufacturing dossier in conformance with DRD in the Annex B.
The PCB manufacturer shall issue to the supplier a MRR checklist, which is part of the l’CB manufacturing dossier, in conformance with the DRD in the Annex B.
NOTE An example of a MRR checklist is given in Annex C.
j. During the MRR, supplier and PC13 manufacturer shall approve the PCB manufacturing dossier, the L’CB definition dossier and all Review Items.
NOTE The approvals are recorded in the MRR checklist.
k. The MRR shall provide authorisation for manufacture to the PCB manufacturer.BS/EN 16602-70-12-2016 pdf download.
BS/EN 16602-70-12-2016 pdf download
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