Smart Battery Charger with SMBus and System Power Selector, Softer Turn-On

The bq24721 is a high efficiency synchronous battery pack charger with high level of integration for portable applications. This device implements a high performance analog front-end that interfaces to the system power management micro-controller through a simplified SBS-like SMBus interface.

The dynamic power management (DPM) function modifies the charge current depending on system load conditions, avoiding ac adapter overload.

High accuracy current sense amplifiers enable accurate measurement of either the charge current or the ac adapter current, allowing termination of nonsmart packs and monitoring of overall system power.

The adapter isolation diode can be bypassed or entirely replaced with an external MOSFET using a control signal provided by the bq24721, thus reducing overall power dissipation.

Integrated features such as charger soft start, charge overcurrent protection, and IC temperature monitoring provide a second level of protection, in addition to pack and system protection functions.