Date: 12/11/2012

Pair of smart ICs from TI for wireless charging

Texas Instruments has come out with single-chip wireless power receiver with integrated battery charger and a new "free-position" transmitter integrated circuit, which expands the charge area by 400 percent. These chips support wireless battery charging in places, such as automotive consoles, charging pads and office furniture.

bq51050B is Qi-compliant wireless power receiver featuring 20-V receiver combines rectification, voltage conditioning, communication control and Li-Ion charging capability all in a single chip. The inductor-free, single-stage design delivers the industry's highest system efficiency and saves up to 60-percent board space compared to a multi-stage implementation, claims TI.

Another chip bq500410A from TI is the first WPC 1.1-ready wireless power transfer controller to support A6 transmitters. The controller allows a Qi-compliant smartphone or other portable device to charge in a surface area of at least 70 mm by 20 mm, 400-percent larger compared to today's 18-mm by 18-mm "bull's-eye" charge space. The bq500410A achieves greater than 70-percent efficiency, and relies on a unique parasitic metal and foreign object detection feature to safely protect the system and stop delivering power if a metal object is detected between the transmitter and receiver.

Availability and pricing : The bq51050B comes in a 1.9-mm by 3.0-mm WCSP package or 4.5-mm by 3.5-mm QFN, and is priced at US$2.75 in 1,000-unit quantities. A bq51051B version with 4.35-V charge voltage is available. The bq500410A comes in a 48-pin, 7-mm by 7-mm QFN package, and is priced at US$3.18 in 1,000-unit quantities.