SDG #166 Creating Ring Light Pick and Place Files for JLCPCB's Assembly Service

This episode moves the LED microscope ring light project from a hand-soldered prototype into a board that can be built by a turnkey SMT assembly house. The focus is the paperwork rather than the hardware: exporting a centroid (pick and place) file and a bill of materials from the EDA tool, then reworking both so the assembler’s software actually understands them.

The practical value here is in the details that trip people up the first time they order assembled boards. Component designators in the BOM have to match the designators in the position file exactly, footprint and value columns need to be present and unambiguous, and every line item has to be mapped to a part number from the assembler’s own stocked library rather than a generic manufacturer code. Parts that are not in stock either need substituting or leaving off for hand fitting later, which is a real design constraint worth considering before routing the board.

Rotation and origin conventions get attention too, because these are the classic causes of parts fitted backwards or offset. Polarised components such as LEDs, diodes and ICs need their rotation values checked against the assembler’s expectation, and the board origin used for the export must line up with the origin implied by the Gerbers. Column headers and units also matter, since the upload parser is fussy about naming and about millimetre versus inch values.

For anyone with a working prototype and a batch of boards to build, this is a useful walkthrough of the file preparation step, and a reminder that a few minutes spent verifying rotations is cheaper than a reel of misplaced LEDs.