The STWBC-WA is STMicroelectronics’ wireless battery charger transmitter application optimized for wearable usage.
Thanks to its 5 V native supply, the STWBC-WA device is ideal to operate with USB power supplies.
Wireless battery charging systems replace the traditional power supply cable by means of electromagnetic induction between a transmitting pad or dongle (TX) and a battery-powered unit (RX), such as a smartwatch or sports gear.
The power transmitter unit is responsible for controlling the transmitting coil and generating the correct amount of power requested by the receiver unit. The receiver unit continuously provides the transmitter the correct power level requested, by modulating the transmitter carrier through controlled resistive or capacitive insertion. Generating the correct amount of power guarantees the highest level of end-to-end efficiency due to reduced energy waste. It also helps to maintain a lower operational temperature.
The digital wireless battery transmitter can adapt to the amount of energy transferred by the coil by modulating the frequency, duty cycles or coil input voltage.
- Digital controller for wireless battery charger transmitters
- Optimized for < 3 W applications
- Smartwatches and healthcare
- Internet of Things (IoT) battery-powered smart devices
- Remote controllers
- Cost effective half-bridge topology with integrated drivers
- Optional full-bridge configuration for 3 W applications
range: 3 V to 5.5 V
- Supports USB VIN
- Active presence detector
- Parametric customization via graphical interface
- 2 firmware options:
- Turnkey solution for quick design
- APIs available for application customization
- Peripherals available via APIs
- ADC, with 10-bit precision
- I2 C master fast/slow speed rate
- Flash and EEPROM with read-while-write (RWW) and Error Correction Code (ECC)
- Program memory: 32 Kbytes Flash; data retention: 15 years at 85 °C after 10 kcycles at 25 °C
- Data memory: 1 Kbyte true data EEPROM; data retention: 15 years at 85 °C after 100 kcycles at 85 °C
- RAM: 6 Kbytes
- Transmitter reference design:
- Evaluation board order code: STEVAL-ISB038V1T
- 2-layer PCBs
- Active object detection
- Graphical user interface for application monitoring
- Interoperable with receiver: STEVAL-ISB038V1R
- Operating temperature
- -40 °C up to 105 °C