Application Notes

The Universal Serial Bus has become one of the most widespread and convenient ways to connect electronic devices to the PC. Countless modern portable products with built-in USB connectors readily use the USB data bus to transmit and receive data to and from PCs, but many of these battery-powered units still use a separate power supply for battery charging (often a charging cradle or a simple AC/DC converter). Sometimes overshadowed by its data bus partner, each USB connection also contains a power bus. With a maximum power rating 5.25V/500 mA, the USB power bus is a great source for charging a single-cell Lithium-Ion battery.