ST STEVAL-WBC2TX70 User Manual

Introduction
The STEVAL-WBC2TX70 evaluation board, based on the STWBC2 integrated circuit (IC), is designed for wireless power
transmitter applications and allows its user to quickly start their 5 W Qi BPP, 15 W Qi EPP or 70 W STSC wireless charging
projects.
The STWBC2 wireless transmitter IC can deliver the following power transfer levels of inductive wireless power technology:
• Up to 5 W charging power compatible with Qi 1.3 Baseline Power Profile (BPP)
• Up to 15 W charging power compatible with Qi 1.3 Extended Power Profile (EPP)
• Up to 70 W charging power using the STSC Profile
The BPP and EPP are specified by the Wireless Power Consortium’s Qi specification.
The evaluation board is designed to operate with 5-20 V input voltage or with a USB PD power adapter.
Two interfaces are open to the user: UART for monitoring and control via STSW-WBC2STUDIO graphical user interface (GUI)
and SWD JTAG for direct NVM access. Both interfaces are accessible via the STLINK-V3MINIE bridge.
The STEVAL-WBC2TX70 includes several safety mechanisms providing over temperature (OTP), overcurrent (OCP),
overpower (OPP), overvoltage (OVP) and Vin drop protections as well as foreign object detection (FOD) for reliable designs.
Figure 1. STEVAL-WBC2TX70 evaluation board
STEVAL-WBC2TX70 wireless power transmitter evaluation board
UM3286
User manual
UM3286 - Rev 1 - March 2024
For further information contact your local STMicroelectronics sales office.
www.st.com

ST STEVAL-WBC2TX70 Specifications

General

Brand	ST
Model	STEVAL-WBC2TX70
Category	Motherboard
Language	English

Summary

Introduction

Getting Started

Reference Design Specifications

Overview of the Board

Device Description and Operation

System Block Diagram

High-level overview of the device's architecture and components.

Power Up Sequence

Describes the step-by-step process from power application to device initialization.

Protections Overview

Summarizes hardware and software protections against overvoltage, overcurrent, etc.

Foreign Object Detection (FOD)

General overview of FOD to prevent damage from foreign objects.

WPC Qi Wireless Power Transfer

Bidirectional Communication

Explains power control via ASK and proprietary communication via FSK.

Firmware Programming and Updates

STM32Cube Programmer

Details the STM32CubeProgrammer tool for reading, writing, and verifying device memory.

UART Firmware Update

Method for automating mass production firmware updates via UART commands.

STSAFE-A110 for Qi Authentication

Qi Authentication Procedure

Outlines the steps and components involved in the Qi authentication process.

Graphical User Interface (GUI)

Connecting STWBC2 to the GUI

Instructions for connecting the STWBC2 board to the STSW-WBC2STUDIO GUI.

Info Page

Provides an overview of the GUI's info page, including status and events.

Device Metrics

Displays real-time operational metrics like frequency, duty cycle, and temperatures.

Parameters Page

Allows configuration and saving/loading of device parameters and settings.

FW Page Operations

Calibration

Explains the calibration process for optimizing performance after firmware updates.

Protection Tuning

Foreign Object Detection Tuning

Tuning FOD for optimal performance based on power balance comparison.

Overvoltage Protection Tuning

Adjusting thresholds for static, dynamic, and ring node overvoltage protections.

STEVAL-WBC2TX70 Description

Schematic Diagrams

Provides detailed circuit diagrams for the STEVAL-WBC2TX70 evaluation board.

Bill of Materials (BOM)

Lists all components used in the STEVAL-WBC2TX70 evaluation board.

PCB Layout

Illustrates the PCB layout for the top, inner, and bottom layers of the board.

STWBC2 Default Configuration

Lists the basic default operating parameters for the STWBC2 transmitter.

Typical Performance Characteristics

Power-Up Waveforms

Illustrates the device power-up sequence using USB PD and its associated waveforms.

Efficiency and Spatial Freedom

Evaluates efficiency and spatial freedom in XY and Z axes under various conditions.

Thermal Performance

Shows thermal performance data under a 70 W load and a 4 mm z-distance.

Designing a Wireless Power Transmitter

BOM Reduction Suggestions

Provides suggestions for reducing the Bill of Materials for custom designs.

Layout Guidelines

Offers general recommendations for designing the PCB layout for performance.

High Power Tracks

Guidelines for designing wide tracks to effectively dissipate heat from high currents.

VIN ISNS Routing

Recommendations for routing VIN ISNS tracks for accurate current measurement.

DC-DC Boost Circuit Routing

Guidelines for placement and routing of the DC-DC boost circuit components.

Board Versions and Compliance

Regulatory Compliance Information

Details FCC, Industry Canada, EU, and UK regulatory compliance statements.