SDG #106 4 Layer PCBs from JLCPCB - Lighting Controller Project Part 6 - Initial Testing

Part 6 of the lighting controller build moves the project off the breadboard and onto a proper four layer PCB, which is a meaningful step up from the two layer prototypes used earlier in the series. Four layers buy you dedicated power and ground planes, and that matters here because a controller switching LED loads needs low impedance returns and a clean supply for the logic side. The video walks through what arrived from the fab, how the finish, drilling and silkscreen registration look on close inspection under the microscope, and whether the extra cost over a standard two layer order is justified for a project of this complexity.

The assembly section is the practical part for anyone building similar boards: hand soldering the fine pitch and passive parts, working through the sequence so that power supply sections can be verified before anything expensive gets fitted, and using a bench supply with current limiting as insurance against a shorted plane or a reversed part. Initial testing follows the same conservative order, checking rail voltages and current draw first, then confirming that the microcontroller and switching stages behave as intended before any load is attached.

What comes out of this episode is a realistic picture of first power-up on a custom board. Expect a mix of things that work immediately and small design issues that only surface with real hardware in front of you, which is exactly why a low cost prototype run is worth doing before committing to a final revision. Useful viewing if you are considering your first move from two layer to four layer boards.