Ultra-Compact PCB Downsizing

My current board is already under 4 sq inches, yet I still need to reclaim every possible millimetre of space. The single overriding goal is size reduction; cost and raw performance can remain as they are as long as nothing regresses.

Scope of the optimisation
• Review the existing schematic and four-layer layout.
• Replace or consolidate the parts below with smaller or integrated alternatives while maintaining electrical behaviour:
– Resistors and capacitors
– Microcontroller
– Connectors
• Suggest routing, via, and stack-up changes that permit tighter clearances without breaching IPC standards.
• Provide an updated BOM, annotated schematic, PCB file (Altium Designer preferred but I can import from KiCad), and manufacturing Gerbers/ODB++.

Acceptance criteria
1. Total board outline reduced by at least 15 % from the current design.
2. No new ERC or DRC errors at 4 mil trace / 4 mil space rules.
3. All original I/O brought out to edge connectors or equivalent test points.
4. BOM substitutions are available through two mainstream distributors.

Hand-off template files will be supplied immediately after project start, together with current impedance targets and stack-up notes.