This document describes a high-efficiency USB power management system that safely charges Li-Ion/Polymer batteries from automotive power supplies. The system is compact, robust, efficient, and easy to design, making it suitable for use in large transient environments.
The document presents a complete USB/Battery Charging Solution designed for large transient environments typical of automotive power systems. The circuit utilizes the LTC4098 USB power manager/Li-ion battery charger controlling an LT3480 HV step-down regulator to seamlessly charge batteries from wide-ranging high voltage or USB sources.
The circuit operates normally when the HVIN input is between 8V and approximately 24V.
The circuit can tolerate voltages of approximately -30V to 100V.