The newest revision of the Open Hardware Laser Scanner board is finally alive! Upgrading to a 4-layer design packed with extra safety features was 100% the right call.
Of course, getting here wasn't without its hurdles. Here is a quick rundown of the crazy bugs I ran into getting this revision off the ground:

The Rogue Power Supply: My Vevor DC power supply completely failed and suddenly started dumping 48V into my 24V rail (I'm pretty sure that violates a regulation or two). Luckily, my TVS diode did exactly what it was supposed to do and saved the board. In my confusion ("wait, why is this broken?"), I measured 24V, removed the diode to test, and accidentally hit the unprotected board with 48V. Incredibly, the board survived! Note to self: always trust the TVS diode.

The Silent TMC2209s (An ESP-IDF Gotcha): My TMC2209 stepper drivers still weren't communicating, which was actually one of the main reasons I spun this new board in the first place. It turns out the culprit was a sneaky change in the ESP-IDF toolchain that altered the UART protocol. Previously, the protocol would let the transmission line float after a successful transfer; now, it actively ties it to 0V. Because of the high drive strength of the ESP32-S3, the standard 1K resistor used between TX and RX for single-wire UART isn't enough anymore. Bumping that resistor up to ~5.4K ohms fixed the issue completely.

A Hot Camera Mistake: I learned the hard way that the camera FFC connector I used was a top-contact style, not bottom-contact. I plugged the ribbon cable in backwards. Fortunately, the camera survived the ordeal, though it got alarmingly hot before I caught the mistake

Minor Schematic Gremlins: The schematic for a basic button was incorrect. A minor inconvenience compared to the rest, but fixed nonetheless.

All in all, the V2 board is a massive step up. The 4-layer stackup makes routing so much cleaner, and having those extra safety features already paid off. Onward to the next step of the build!

Board was purchased from PCBway. We thank PCBway for the sponsorship of the previous board and they will be featured in upcoming video. For now it was easier to simply purchase instead of relying on sponsorship.