Dallas—Texas Instruments' bq24721 is the company's first integrated battery charge controller with a system management bus (SMBus) interface aimed at three- to four-cell, multi-chemistry battery packs (to 19.2 volts) used in portable applications.
The bq24721, a NMOS-NMOS synchronous DC/DC buck converter that operates at a user selectable 300 or 500 kHz, offers a charge voltage regulation accuracy of 0.4 percent, and two percent output current accuracy. Using a synchronous NMOS-NMOS rectifier, the device achieves power efficiencies up to 94 percent.
Additional features include a system power selector function, which automatically selects the AC adaptor or the battery to properly manage the system load. The device’s dynamic power management (DPM) function controls the charge current depending on system load conditions, thus avoiding AC adapter overload. In addition, high accuracy current sense amplifiers enable accurate measurement of either the charge current or the AC adaptor current, allowing termination of "non-smart" packs and monitoring of overall system power.
Click here for additional product information. The bq24721, in a 32-pin, 5-by-5 mm QFN package, has a suggested retail price of $4.90 each in 1k quantities. Evaluation modules, application notes and the company's comprehensive portfolio of battery management ICs are available through power.ti.com/battman.
Texas Instruments, 1-800-477-8924, www.ti.com