Here are some great tips for making your BOMs from Screaming Circuits:
The question of the day is: “What makes a good BOM?” There are a lot of BOM formats in use. It’s one area that the standards train more or less left behind. Well, there are standards. For example, IPC-2581 covers not only BOM standards, but a replacement for Gerbers and the whole manufacturing data package. One of these days, we’ll all be using the IPC-2581 formats for our data and life will be beautiful all of the time.
And here is his list of pointers to consider:
- "BomItem" or "Item #": This is just the line number. Each type of part gets an item line, not each part. If the pat number is the same, you just put it down once and give the quantity.
- "quantity" or "Qty": How many of this specific part you need per board
- "RefDes": The reference designators used by the parts on the PCB silk screen. All of the same part number should be in the same excel spreadsheet cell: i.e., "R3, R4, R5, R6". You can also indicate a contiguous range with a dash: "R3-R6" or "R3-R6, R10, R15"
- "Manufacturer" or "Manf": The name of the component manufacturer. It's best to spell out the full name, e.g., "Texas Instruments", but common abbreviations such as "TI" generally work too. The less ambiguity, the better.
- "Mfg Part #" or "Manufacturer Part #": The part number that you would use if you were buying this exact part from the manufacturer or a distributor. All of the suffixes are important too. For example, "PIC16F88" is not enough when you really need a "PIC16F88-I/P".
- "Dist. Part #" or "Distributor Part #":Not strictly necessary, but can help in cases with a bit of ambiguity. Again, this would need to be the exact part numer as you would order it from that distributor.
- "Description"or "Desc": This is the component description as given by the manufacturer. Again, this isn't strictly required, just a good idea.
- "Package": This is the standard package type, e.g., "SOT-23", "TO-92", "0201". Again, not strictly necessary but can be a good redundant check.
- "Type": Optional indicator of the generic type. e.g., "fine pitch", "smt", "thru-hole", "Leadless". Not required but can help with assembly quoting.