'Industry's smallest' battery charger extends run-time

10th September 2014

Siobhan O'Gorman

0 0

A linear battery charger, claimed to be the industry’s smallest with the lowest power, has been introduced by Texas Instruments. The company have also introduced fully integrated DC/DC power modules. Offered in a 0.9x1.6mm WCSP, the bq25100 single-cell Li-Ion charger is half the size of existing chargers. The charger supports input voltages up to 30V, allowing accurate control of fast-charge currents as low as 10mA or as high as 250mA.

To support small Li-Ion coin batteries, the charger also allows a charge termination down to 1mA. A leakage current of less than 75nA is also supported by the bq25100, extending standby operation. By using the charger with the bq51003 2.5W, Qi-compliant wireless charging receiver, designers can add wireless charging capability to small portable and wearable applications.

Supporting 200mA output current with 95% conversion efficiency, the TPS82740A and TPS82740B step-down converter modules consume only 360nA of quiescent current during active operation and 70nA during standby. Based on 9-bump MicroSiP package, the modules incorporate a switching regulator, inductor and input/output capacitors. Measuring only 6.7mm², TI claims the modules 75% smaller than existing modules. The TPS82740A supports output voltages from 1.8-2.5V, while the TPS82740B supports 2.6-3.3V in 100mV steps, meeting the power requirements of microcontrollers.

Available from the TI eStore, the bq25100 is priced at $0.75 and shipped in 1,000 unit quantities. The TPS82740A and TPS82740B power modules, which are priced at $1.55 and shipped in 1,000 unit quantities, can be ordered with the TPS82740AEVM-617 and TPS82740BEVM-617 evaluation modules to simplify design. To further reduce development time, the PSpice transient module simulation software is also available to customers.