STMicroelectronics STEVAL-ISB68WA

Overview

STEVAL-ISB68WA from STMicroelectronics is a Qi-compliant wearable wireless power receiver reference design built around the STWLC68 IC, delivering a regulated 5 V output at up to 2.5 W. It integrates FOD, 400 kHz I²C interface, and a compact 10×10 mm PCB layout optimized for small-form-factor wearables such as smart rings and hearables.

For engineers reviewing the STEVAL-ISB68WA datasheet, STEVAL-ISB68WA pinout, STEVAL-ISB68WA application, or STEVAL-ISB68WA equivalent, this kit provides immediate evaluation of STWLC68-based Qi 1.2.4 receiver behavior, real-time configuration via GUI, and hardware-ready integration with host microcontrollers through programmable interrupt and I²C control signals.

Technical Context

The STEVAL-ISB68WA implements a complete inductive wireless power receiver system compliant with Qi 1.2.4, using the STWLC68 as its core IC. It supports foreign object detection (FOD) based on dynamic parameter monitoring and delivers regulated 5 V output without external LDO, leveraging the STWLC68's integrated synchronous rectifier and buck converter.

Communication occurs over a 400 kHz I²C bus routed to an onboard USB-to-I²C bridge (MCP2221), enabling real-time register read/write and event monitoring via STSW-ISB68GUI. The board includes a status LED and open-drain MCP_INTB signal to notify host systems of power handshake completion or fault conditions.

Key Specifications

Availability

STEVAL-ISB68WA is available at Aetrix Electronics and suitable for wearable development, Qi compliance validation, and low-power wireless charging integration requiring stable component supply and rapid prototyping capability.

Supply support for STEVAL-ISB68WA includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, designing and manufacturing analog, MCU, power, and sensor solutions for industrial, automotive, and consumer applications.

The STEVAL-ISB68WA belongs to ST's wireless power reference design portfolio, engineered specifically to accelerate development of compact, Qi-certified wearable receivers using the STWLC68 single-chip solution.

FAQ

Does STEVAL-ISB68WA require external firmware or driver installation?

No. The kit operates out-of-box with the free STSW-ISB68GUI software and the included MCP2221-based USB-to-I²C dongle. No device drivers beyond standard Windows/macOS USB CDC class are needed; GUI auto-detects the dongle and communicates directly with STWLC68 registers via I²C.

Can the output voltage be reconfigured to values other than 5 V?

No. The STEVAL-ISB68WA implements the STWLC68 in fixed 5 V output mode only, as confirmed by its default configuration and schematic (no external feedback resistors or DAC connections). Voltage adjustment requires a different STWLC68-based design with configurable VOUT pins.

Is the receiving coil replaceable or customizable on this board?

Yes. The board uses a discrete 15 mm diameter planar coil (not embedded), mounted with solder pads and test points labeled "COIL+" and "COIL−". Users may desolder and replace it with custom coils, provided impedance and inductance remain within STWLC68's 10–25 µH operating range.

What host interfaces does STEVAL-ISB68WA expose besides I²C?

Only I²C and the open-drain MCP_INTB interrupt signal are exposed for host interaction. There are no UART, SPI, or analog outputs. The interrupt pin (labeled "MCP_INTB") asserts low on power-on, fault, or FOD events and is electrically compatible with 1.8 V–5 V logic inputs.