DC/AC inverters are used to convert automotive 12V into household AC. This project was taken over at proof of concept stage and delivered as a production hardware design. The design is a 400W modified sine wave inverter in 120/230 VAC output versions. The DCDC stage is semi-resonant and capable of supporting AC loads through start-stop events. Start-stop is an emerging feature designed to improve fuel economy by shutting off the vehicle’s internal combustion engine when it is at a stop. The challenge is that when the engine is automatically re-started, the system voltage can dip momentarily to as low as 6V. For standard push-pull DCDC topologies, this is too low to continue to provide AC output. Key challenges in this engagement: New topology simulation/tuning, major BOM cost reduction, control development, thermal management, and radiated/conducted emissions.