From the project's own overview document (author-written).
104 × 104 mm, 4-layer JLC04161H-7628, 2.000 mm corner arcs. Machine-pin datum 96.000 × 96.000 mm.
Carries the motor, passes the three phases from the ESC through to the motor leads, and hosts the RP2350A+ADS1220 molecule (N2) and a PiProbe (N1).
The machine contacts sit upstream of the molecule's RC filter, so anything the carrier picks up arrives unfiltered at the bridge's 350 Ω source. The layout follows from that:
+5V_REF1 and +5V_REF2 are separate nets with no carrier-side tie to +5V. They merge only
inside the molecule. See 03-Molecule/Overview.md for the ratiometric topology this preserves.
The FC and the nested PiProbe both reach the molecule's RX line. debugprobe drives its UART TX from power-up regardless of USB enumeration, so a populated probe holds that pin continuously.
Net-(N1-TX) : N1.9 (PiProbe TX), R1.1 two pads only
/UART0_RX : MC18 (FC), N2.14 (molecule RX), R1.2
R1 = 300R 0603 1 % sits on a 4.31 mm stub in the PiProbe branch alone. The probe reaches the net only through R1; the FC and the molecule's RX connect directly.
contention 3.3 / (300 + 50 + 50) = 8.25 mA
R1 dissipates 300 x 8.25mA^2 = 20 mW of 100 mW
FC drives 0 3.3 x 50/400 = 0.41 V valid LOW
R1 is not in the BOM — it has no LCSC field.
Three large contacts (Ø2.62 hole / Ø4.40 ring, ~20.8 A each), one per phase, into a 4-layer pour with 49 vias at 2 mm pitch per phase, out to 8 × 8 mm wire pads with a 2.0 mm hole.
Phase copper is 12.02 mm × 4 layers = 1.207 mm², 0.214 mΩ over the 15 mm run.
/nRST reaches both MC16 (FC) and MC13 (Scaffold). Wire one end only, or make both open-drain.
There is no external pull-up on either board — only the RP2350's internal 32–86 kΩ./SWD and /SWCLK on MC22/MC24 are an external-probe landing. Keep them out of the FC harness./I2C0_SCL and /I2C0_SDA on MC20/MC21 have no destination; the FC carrier has no I2C contacts.A passive carrier baseplate. It mounts the BLDC motor, passes the motor's three phases straight through from the ESC to the motor leads, routes two load-cell channels, and nests the RP2350A + ADS1220 acquisition molecule and a PiProbe over its machine-pin datum. It carries no active silicon of its own beyond a single arbitration resistor — its job is mechanical location and clean analogue routing.
Two carrier slots (16 × 32 mm): N2 takes the RP2350A / ADS1220 acquisition molecule, N1 takes a PiProbe debug molecule. Each seats over the carrier's machine contacts as an already-populated sub-assembly. R1's placement (below) lets N1 and N2 sit without conflict.
The three motor phases — A, B, C (J1 / J2 / J3) — pass from the ESC through the carrier to the motor leads. These are solder-pad terminals; they carry no 3D body in the STEP export, so they appear in the section legend but not as dropped parts in the viewer.
Two JST-PH 5-pin connectors (J4 / J5) — Load Cell Conn. 1 and 2. The analogue pairs run at a constant 0.45 mm pitch on B.Cu with no vias, referenced to the In2 GND plane. The machine contacts sit upstream of the molecule's RC filter, so what the carrier picks up arrives unfiltered at the bridge's source — which is why the routing is disciplined.
A single resistor keeps the debug bus clean: R1 = 300 R (0603, 1%). The PiProbe reaches the /UART0_RX net only through R1, while the flight controller and the molecule's RX connect directly — so a populated probe (whose debugprobe drives its TX from power-up) never contends the bus, and R1 dissipates only ~20 mW of its 100 mW rating under contention.
The 96 × 96 mm machine-pin datum — 25 contacts (MC1–MC25) plus four corner large pins (MP1–MP4) — locates the carrier in the cell and passes signals to the nested molecule.
Four mounting holes (H1–H4) fix the carrier to the base plate.
Interactive PCB — click any pad, trace or zone to highlight its whole net; hover for pad and live part data.
Interactive schematic — hover a symbol for its KiCad highlight plus live MPN / stock / price / LCSC.