Follow energy and information through the robot
Map power entry, switching stages, motors, encoders, communications and control processing. Mark where each signal leaves the board and travels through a harness or moving joint. The physical installation can dominate a connection that looks short and simple in the schematic.
TI's motor driver layout guidance treats layout as part of the drive design. Use the selected driver's current documentation to review switching loops and sensing, then assess how the compact computing region interacts with those structures.
Decide whether functions should share one board
Combining motor power and control electronics can reduce connectors and assembly operations. Separating them can make cooling, testing and replacement easier. Compare these architectures against actual joint volume, cable movement and repair expectations rather than selecting one solely for a smaller component count.
If the functions share a board, define placement and return path intent before routing. A denser via pattern is not a substitute for understanding how motor current and sensitive feedback return through the assembly.
Review the mechanical duty of the PCB
Include mounting, connector retention and harness strain in the layout review. Consider how the board will be installed, accessed and removed. A connector hidden behind a heatsink may save top view area but make a field replacement unnecessarily difficult.
- Check encoder and sensor routes near switching circuitry.
- Identify power paths and thermal interfaces that constrain copper.
- Reserve diagnostic access in the installed enclosure.
- Record moving harness exits and fastening keepouts.
Test combinations, not isolated functions
Evaluate sensing and communication while the intended motor modes are active. Record load, motion profile and power source with measurements. An encoder that behaves well with a stationary motor may expose a different issue during switching or rapid acceleration.
Keep software configuration and board construction tied to the test record. Before reducing board area on a later revision, compare the previous current paths, feedback geometry and mechanical supports. A routing cleanup should not silently alter a validated relationship.
Adjacent-layer access, one connection at a time
Dielectric · geometry + material
Core or build-up dielectric
Illustrative only. Copper thickness, dielectric construction and via spans require a reviewed stackup.
Common questions
Should a motor power stage use microvias to save space?
Choose its interconnects from current, thermal, mechanical and fabrication requirements. HDI may serve the nearby controller while other structures serve the power path.
Is one integrated robotics board always cheaper?
Not necessarily. Compare assembly, cooling, test, repair and replacement costs in addition to PCB fabrication and connector cost.
References & further reading
Method & assumptions · General design guidance. Validate the proposed construction and acceptance criteria for your project.