Compact 300W LiFePO4 Solar Inverter

I’m ready to commission the complete electronic design for a 150-300 W pure-sine-wave solar inverter that will run from a 12.8 V / 100 Ah LiFePO4 pack and deliver 220 VAC. The unit must operate reliably indoors and outdoors, fit comfortably within a 10 × 20 cm footprint, and meet commercial-grade durability standards. Core electrical requirements • True sine-wave topology with ≥90 % efficiency under typical load • Clean 220 VAC output, THD ≤3 % at 150 W, full-power capability to 300 W • Input 12 VDC nominal, LiFePO4 profile charging via high-frequency PWM • Integrated SoC display or LEDs for real-time battery percentage and charge status Protection & safety Over-temperature shutdown, overload limiting, and fast-acting short-circuit protection are mandatory. Design choices must reflect these protections (e.g., NTC placement, current-sense shunt sizing, MOSFET SOA calculations). Mechanical expectations All magnetics, heatsinking, and component heights must stay inside the 10 × 20 cm PCB outline while allowing airflow and conformal coating for outdoor exposure. Deliverables 1. Full schematic with design notes explaining part selection, especially power devices, magnetics, and protection circuitry 2. Optimised multilayer PCB layout (Altium, KiCad, or Eagle) ready for Gerber/ODB++ release 3. Complete, cost-ed Bill of Materials with supplier MPNs and a short justification column for each critical part 4. Firmware (if a microcontroller handles PWM charging or display) with source code and commenting 5. Test plan covering efficiency, load regulation, protection trip points, and thermal performance Acceptance criteria • Prototype simulation or bench data showing ≥90 % efficiency at 200 W, safe operation up to 300 W • All three protections proven in the test report • No hotspot exceeding 90 °C at 40 °C ambient during a one-hour 250 W run If you’re experienced in compact inverter design and comfortable working to these commercial specs, I’m ready to move quickly.