Power supplies used in automotive applications are usually subject to much harsher conditions than those used in commercial or industrial stationary applications. This application note is intended to guide engineers in designing an

isolated DC-DC flyback power supply using the InnoSwitch3-AQ family of ICs for automotive applications.

The InnoSwitch3-AQ devices dramatically simplifies the design and manufacture of isolated flyback power converters in automotive applications. They combine primary and secondary controllers and safety-rated feedback, allowing accurate output voltage regulation even with a wide input voltage range of 30 VDC to > 1000 VDC. The ability to start up from 30 V input makes them ideal for functional safety critical emergency power supplies.