Change board shape from circular (60mm) to rectangular with slots for better vibration resistance and integration into a 3D-printed avionics sled/rail system (rotate stack 90 degrees for vertical mounting along flight axis)
Switch from M5 to M3 bolts and spacers. Change mounting holes from 5.2mm to 3.2mm; ensure spacer height matches inter-board header mating depth so load is on standoffs, not headers.
Replace 10-pin through-hole JTAG connector with 5-pin 90-degree female SMD header (pointing outward for accessibility); (We can delete the baseplate now.)
- This is the connector: https://www.snapeda.com/parts/5023860570/Molex/view-part/?t=5023860570&ab_test_case=b
-
New pinout is:
-
Replace all TO-220 P-channel MOSFETs with SMD equivalents (e.g., SOP-8 or SOT-223).
Add reference designators (RefDes like R1, C1, U1) to every component on silkscreen (remove non-essential art like rage comics to make space).
- We keep the memes. but we need to make space for the RefDes.
-
How do we add them back?
-
Tools → Update footprints from library →
-
-
Text size: 1mm.
-
Add loop-style test points on all power rails, GND, communication lines (e.g., CAN_H/L), MCU-driven pins, and fault signals; label with net names (e.g., 3V3_LOGIC) on silkscreen.
- https://www.snapeda.com/parts/S2761-46R/Harwin/view-part/?t=S2761-46R&ab_test_case=b, this is the one we will use.
Use IPC Size L (large) footprints for all components to improve solder joint strength against vibration.
Stake (glue) large/heavy components (e.g., caps, connectors) with epoxy (DP2216) or RTV silicone.
Swap fragile connectors: U.FL to edge-mounted SMA for RF; XT/JST-XH/ to positive-locking types (e.g., Molex NanoFit/MiniFit or Harwin Gecko).
Add pinout labels (e.g., Bat+, GND) on silkscreen for all connectors.
Add 0-ohm jumpers (resistors) for isolating functional blocks during debugging.
Ensure parts are rated -40°C to +85°C and available.
Perform power dissipation calculations, trace voltage drop/temp rise checks, and ensure 1A per via minimum; double capacitor voltage ratings; simulate power circuits (worst-case analysis); align power connectors consistently across boards for wiring/debugging.
Add Belleville washers under nuts for thermal preload maintenance; use torque wrench for assembly.
Change SWDIO[number] net on every board to just be SWDIO
Add new battery connector:
