Circuitwise has released guidelines on what constitutes a perfect set of information required to quote and then manufacture an assembled printed circuit board. The guideline encompasses the Bill of Materials (BOM), Gerber files, assembly instructions and production management.
Every design for an electronic circuit board assembly has a BOM which itemises the parts required for the board. Considering how common BOMs are, you would think to compile them is a straight forward process. However, even an experienced designer can forget important details.
The guideline is in the form of a checklist with accompanying explanatory text. Experienced designers can use the checklist as a simple reminder of what they should include in their BOM and other information.
For less experienced designers, the guidelines will explain why the information required is important. It also outlines the options you have.
As an example, the most important part of a good BOM is to define the criticality of each part – the tolerance for variation in the part specification. High criticality means the part must be exactly supplied as specified – usually a specific part number from a specific manufacturer or supplier.
If a BOM does not specify the criticality of a part, then we are forced to assume every component is critical. This shortfall prevents us from shopping around globally to get the best price and lead time on a component.
To read about all 29 categories of information in our guide, download the checklist from our website.