The TPS65820 power IC is designed to handle 2 A of input current from the adaptor and up to a 3.5-A discharge from the battery. The charger algorithm is designed to charge a single-cell, Li-ion or Li-polymer battery. The buck, boost, and LDO supplies typically run off of the OUT (system) pin which is available on the IC and is powered from the AC, USB, or battery.
The EV2300 is a USB-based interface board for a PC that can be used to evaluate battery fuel gauge circuits designed with Texas Instruments' ICs. The EV2300 has connections on it for a USB cable and also accepts inputs from a battery fuel gauge circuit's communication port (SMBus or HDQ). By running the appropriate PC software for the corresponging fuel gauge IC, the EV2300 interface board allows the user to evaluate the battery fuel gauge circuit.