Charging controller meets Qi Extended Power profile

Major mobile manufacturers are committing to wireless charging by joining the industry alliances and launching compatible products to enable users to put their mobiles down to charge in just a few minutes. The Wireless Power Consortium (WPC) has introduced the Extended Power Qi profile for faster charging. By raising the maximum charging power from 5.0 to 15W, to enable devices to be charged up to three times more quickly.

The controller consumes just 16mW in standby and is able to wirelessly transfer more than 80% of the total input power. The company has patented enhanced active presence detection to wake the system quickly when a compatible object is presented for charging. The patented technology also enhances the performance of foreign object detection (FOD), to cut power and prevent overheating if objects containing metals are brought too close to the charger.

A step-up (boost) DC/DC converter and a controller are integrated. The Qi charging algorithms are implemented in firmware to save integrating software and an additional microcontroller in designs. Together, the converter and controller generate the input power and the control signals for an external half-bridge power stage that drives the charging transmitter antenna. Designers can optimise the external half bridge and its associated gate drivers for use with any supply voltage from 5.0 to 12V, and to ensure compatibility with USB quick chargers.

The evaluation kit, STEVAL-ISB044V1, includes a 15W Qi MP-A10 reference design, 12V 2A AC/DC adapter, a USB/UART dongle for connection to the PC and USB cable, as well as pre-loaded firmware. In addition to the supporting documentation, a graphical PC-based configuration tool can be used to customise settings.

The STWBC-EP is available now, as a 32-lead QFN (5.0 x 5.0mm) device.