SDG #189 JLCPCB NEW UPDATES to SMT Assembly Service!

This episode examines how JLCPCB’s SMT assembly (PCBA) offering has changed, and what those changes mean when deciding between hand populating boards and paying to have them machine assembled. The focus is practical rather than promotional: which parts are actually stocked, what happens when a component in the BOM is not in the library, and how the extra fees accumulate once stencil, setup and per joint charges are added to the base PCB price.

Key ground covered includes the expanded component library and the shift away from being limited to a small basic parts list, support for placement on both sides of a board rather than the top layer only, and larger allowable board sizes. There is also discussion of the ordering workflow itself, which is where most first time PCBA orders go wrong: exporting a BOM with correct designators and LCSC part numbers, generating a component placement (CPL or pick and place) file with consistent origin and rotation data, and reviewing the online placement preview before confirming, since a rotated polarised part is the classic failure mode.

The useful conclusion for a hobbyist is a cost threshold. For a handful of prototypes with only a few passives, hand soldering with paste and hot air is still cheaper and faster. Once a design includes fine pitch QFNs, BGAs, dozens of 0402s, or more than about five identical boards are needed, paid assembly starts to look reasonable, especially when the alternative is buying reels of parts that will never be used again. The episode is worth watching before committing a first PCBA order and discovering the extra line items at checkout.