New Industry Products

Texas Instruments Unveils New bq2400x Family of Battery Chargers

September 28, 2000 by Jeff Shepard

Texas Instruments (TI, Dallas, TX) unveiled a new family of battery chargers, the bq2400x, intended to allow designers to reduce the size of their full battery-charger circuit by more than 55 percent. The bq2400x family offers features aimed to cut design effort, reduce component count, minimize overall system cost and improve time-to-market. TI claims that all this makes the bq2400x family suited for portable battery-powered electronics, such as wireless phones, pagers, personal digital assistants, audio players and cameras.

Other features of the new bq2400x family include a 1.2A MOSFET pass transistor and a reverse-current blocking Schottky diode with a combined maximum dropout voltage of 0.7V, making it possible for designers to build a full battery-charger circuit within a 44mm square footprint. In addition, TI claims that the devices perform a highly accurate, programmable charge algorithm, including preconditioning for deeply discharged cells as well as voltage, temperature and time monitoring for safety. The devices also include a safety timer so that if preconditioning fails to produce the desired result, the battery is presumed damaged and charging stops.

The bq2400x monitors both its own temperature and, through an external thermistor, the battery's temperature. Internal temperature measurements check the MOSFET and Schottky diode. If these or the battery become too hot, the device has been designed to automatically halt charging. Patrick Heyer, marketing manager of battery-management products at TI, maintains that in today's portable market, designers are continually looking at ways to reduce board space and time-to-market without dramatically impacting the overall system cost. These new devices are the industry's first charge-management ICs to combine an integrated MOSFET and Schottky diode with advanced management features, such as preconditioning, charge algorithms and termination.

Suggested resale prices for the bq2400x charge-management ICs start at $1.89 each in quantities of 1,000. Units will be available in volume in November. The units also come in a thermally enhanced 20-lead TSSOP PowerPad package.