MCP73831 Charger Module: Charge Status Is Not a System Power Path

This is an unbuilt educational design candidate.

Complete offline arithmetic tool for exact prototype current, first-order heat and current balance; not firmware, charger simulation or battery safety evaluation.

On a computer: python3 test_charger_budget.py
For the calculator, run python3 charger_budget.py

The SVG is editable vector source; PNG is its raster rendering. The circuit contract contains exact physical pin and pad requirements. Observations CSV is deliberately blank. Native EasyEDA/OSHWLab project identity, ERC/DRC, assembly, thermal qualification and physical results require separate evidence; this ZIP proves none of them. Do not order a board from this author package.
