Issue link: https://iconnect007.uberflip.com/i/1248324
58 PCB007 MAGAZINE I MAY 2020 MIL-PRF-31032 This specification covers the generic per- formance requirements for rigid and flexible PWBs with plated holes, that will use solder- ing for component/part mounting. Introduced in 1997, it also covers PWBs fabricated to MIL- PRF-55110 and MIL-PRF-50884. MIL-PRF-31032 is segregated into the follow- ing six board types (each covering a major de- sign group): 1. MIL-PRF-31032/1: Multilayer Rigid 2. MIL-PRF-31032/2: Single- and Double-Sided Rigid 3. MIL-PRF-31032/3: Multilayer Flex and Rigid-Flex 4. MIL-PRF-31032/4: Single- and Double- Sided Flex 5. MIL-PRF-31032/5: Multilayer Rigid High Frequency 6. MIL-PRF-31032/6: Single- and Double- Sided Rigid-High Frequency Key Features of MIL-PRF-31032 Today's military printed board industry has evolved a great deal since the generic qualifica- tion concept was first added to MIL-PRF-55110 and MIL-P-50884. In the past, the DoD drove leading-edge technology, and the commercial industry followed. Most printed board manu- facturers were captive facilities building prod- ucts for specific systems. Today, the commer- cial industry has much to offer the DoD in the way of technology and cost savings. The quali- fied manufacturers list (QML) concept of MIL- PRF-31032 attempts to capture these best com- mercial practices and apply them to military products. The QML concept in MIL-PRF-31032 allows both the printed board manufacturers and the user community to take advantage of best com- mercial practices while still retaining govern- ment oversight to assure printed boards meet the needs of the end-item military user. QML results in quick implementation of new tech- nology into military systems at a higher level of quality and reliability, and at a lower price [1]. Unraveling the 'Twist' From MIL-PRF-55110 Rev H with Amend- ment 3: 1. B.1.1 Scope. This appendix contains optional requirements concerning the QML product assurance level (MIL-PRF-31032) for PWBs covered by this specification. This appendix is a mandatory part of the specification when the product assurance level of appendix A is not used. 2. B.3.1 Performance requirements. The performance requirements of the appli- cable MIL-PRF-31032 specification sheet shall apply to all PWBs procured to the QML product assurance level. 3. B.3.2 Accept/reject criteria. The accept/reject criteria of the applicable MIL-PRF-31032 specification sheet shall apply to all PWBs procured to the QML product assurance level [2] . From MIL-PRF-50884 Rev F with Amend- ment 3: 1. B.1.1 Scope. This appendix contains optional requirements concerning the QML product assurance level (MIL-PRF-31032) for PWBs covered by this specification. This appendix is a mandatory part of the specification when the product assurance level of appendix A is not used. 2. B.3.1 Performance requirements. The performance requirements of the applicable MIL-PRF-31032 specification sheet shall apply to all PWBs procured to the QML product assurance level. 3. B.3.2 Accept/reject criteria. The accept/reject criteria of the applicable MIL-PRF-31032 specification sheet shall apply to all PWBs procured to the QML product assurance level [3] . To summarize, if the site is certified to MIL- PRF-31032, it can build any parts where the master drawing indicates MIL-PRF-55110 or MIL-PRF-50884.