STMicroelectronics has introduced new transmitter and receiver evaluation boards to streamline the development of Qi-compliant wireless chargers up to 15W. These boards, based on the company’s STWLC38 and STWBC86 ICs, are designed to facilitate the rapid prototyping and testing of wireless charger systems.
The STEVAL-WLC38RX board, featuring the STWLC38 5W/15W receiver IC, and the STEVAL-WBC86TX board, containing the STWBC86 5W transmitter IC, are instrumental in building wireless charger prototypes efficiently. Both boards are compatible with the STSW-WPSTUDIO graphical software environment, which assists in the development process.
The STWLC38 receiver IC is notable for its support of the Qi 1.3 15W Extended Power Profile (EPP) and 5W Baseline Power Profile (BPP). It also functions as a 5W transmitter, enabling reverse power transfer for device-to-device charging. The IC incorporates a synchronous rectifier and a low-dropout (LDO) linear regulator, converting power from the receiver coil to a programmable DC output voltage between 4V and 12V. Its power-transfer efficiency reaches up to 85%. Additionally, ST’s Adaptive Rectifier Configuration (ARC) mode enhances the receiver-detection distance by 50%, offering increased spatial freedom for device positioning and optimal power transfer.
On the transmitter side, the STWBC86 Qi 1.2.4 BPP-compatible 5W transmitter IC integrates a high-efficiency, low-impedance full-bridge inverter and drivers. This design minimizes power dissipation and reduces the bill of materials. The IC manages the energy transferred through the transmitter coil by adjusting the PWM frequency and duty cycle.
Both ICs are designed to operate with a wide input-voltage range, making them suitable for a variety of consumer and industrial products. They are dynamically managed by an Arm® Cortex®-M0+ digital core for optimal efficiency. The integrated non-volatile memory (NVM) supports advanced features and allows for firmware updates to accommodate protocol evolution.
Designed for compact applications, the STWLC38 wireless power receiver and the STWBC86 transmitter are housed in small chip-scale packages, measuring 2.12mm x 3.32mm WLCSP40 and 3.26mm x 3.67mm WLCSP72 respectively. Both ICs include built-in thermal management and electrical protection.
The evaluation boards are tailored to expedite the development of wireless charging solutions for a diverse range of applications. These include consumer electronics like smartphones, tablets, smartwatches, and wearables; medical devices such as personal medical devices, drug-delivery systems, and portable ultrasound devices; as well as other products including toothbrushes, shavers, computer peripherals, hearing aids, charging cases, power tools, and mobile robots.
Both the STEVAL-WLC38RX receiver board and the STEVAL-WBC86TX transmitter board are currently available on www.st.com, priced at $72.28 and $84.53 respectively.