The TPS65217C is a single chip power management IC designed specifically to support the AM335x series of application rpocessors in portable and 5 V, non-portable applications. It has a linear battery charger for single-cell Li-ion and Li-Polymer batteries, dual-input power path, three step-down converters, four LDOs, and a high-efficiency boot sconverter to power two strings of up to 10 LEDs each.
This is the chip that inspired most of the power supply designs. We were intrigued because it offered safe charging of a single cell li-ion battery-just like a cellphone. This chip is on the Beaglebone board from the factory and is responsible for providing stable system voltages for the Beaglebone Black (processor memory, Ethernet, and USB) as well as power monitoring with I2C support.
The above schematic is from the Beaglebone Black documentation.