Description

STWBC

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DocID027322 Rev 3

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Description

The STWBC is the digital controller for wireless battery charger (WBC) transmitters (TX)

from STMicroelectronics, offering the most flexible and efficient solution for controlling

power transfer to a receiver (RX) in WBC-enabled applications such as phones, wearables,

and other battery powered devices that use electromagnetic induction for recharging.

As a member of the Qi Wireless Power Consortium and the PMA (Power Matters Alliance),

ST ensures full compatibility with these leading wireless charging protocols and holds

certification for the Qi 1.1.2 A11 standard.

The STWBC performs all the functions for transmitter control: thanks to the internal 96 MHz

clock and supporting both half-bridge and full bridge topologies, it is able to precisely control

the amount of transmitted power to match the requirements of the receiving unit in terms of

maximizing the efficiency of the power transfer.

The STWBC comes with firmware options to offer customers the ability to personalize their

end product without the need of external microcontrollers:



A turnkey Qi 1.1.2 A11 certified solution, fully interoperable with Qi enabled mobile

phones.



API (application programming interface) access to customize the underlying firmware,

for example modifying the behavior of the LEDs or GPIOs in response to the receiver

behavior and supporting I²C and UART communication within a network.

The STWBC Qi 1.1.2 A11 certified solution is available in the STMicroelectronics STEVAL-

ISB027V1 reference design, intended for all Qi compatible receivers such as in Qi enabled

mobile phones.

In the reference design the STWBC integrates the foreign object detection (FOD): the digital

feedback between TX and RX units allows the detection of metal objects close to the

receiver that could result in potential hazards, enabling the STWBC to stop power

transmission when such objects are detected.

The reference design is offered together with a complete ecosystem to support customers in

building their applications, including the Qi 1.1.2 A11 certified board (STEVAL-ISB027V1),

API libraries and documentation to develop software customizations, as well as

a comprehensive graphical user interface to monitor real-time performance and diagnostics.