原标题：ST STWLC04+ STWBC-WA 1W无线充电系统解决方案

　　ST公司的STEVAL-ISB038V1是采用发送器STWBC-WA和接收器STWLC04的1W可穿戴无线电源系统.发送器20mm线圈,接收器11mm线圈,无线功率传输1W,主要用在超紧凑的电池工作的设备如智能手表,无联网(IoT)传感器和医疗设备.本文介绍了无线充电系统架构图,1W可穿戴无线电源系统STEVAL-ISB038V主要特性和电路图,材料清单以及发送器STWBC-WA和接收器STWLC04主要特性和框图.

　　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 powersupplies.

　　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-poweredunit (RX), such as a smartwatch or sports gear.

　　The power transmitter unit is responsible for controlling the transmitting coil and generatingthe correct amount of power requested by the receiver unit. The receiver unit continuouslyprovides the transmitter the correct power level requested, by modulating the transmittercarrier through controlled resistive or capacitive insertion. Generating the correct amount ofpower guarantees the highest level of end-to-end efficiency due to reduced energy waste. Italso helps to maintain a lower operational temperature.

　　The digital wireless battery transmitter can adapt to the amount of energy transferred by thecoil by modulating the frequency, duty cycles or coil input voltage.

　　STWBC-WA主要特性:

　　 Digital controller for wireless battery chargertransmitters

　　 Optimized for < 3 W applications

　　– Smartwatches and healthcare

　　– Internet of Things (IoT) battery-poweredsmart devices

　　– Remote controllers

　　 Cost effective half-bridge topology withintegrated drivers

　　 Optional full-bridge configuration for 3 Wapplications

　　 VIN range: 3 V to 5.5 V

　　– Supports USB VIN

　　 Active presence detector

　　 Parametric customization via graphicalinterface

　　 2 firmware options:

　　– Turnkey solution for quick design

　　– APIs available for application customization

　　 Peripherals available via APIs

　　– ADC, with 10-bit precision

　　– UART

　　– I2C master fast/slow speed rate

　　– GPIOs

　　 Memory

　　– Flash and EEPROM with read-while-write(RWW) and Error Correction Code(ECC)

　　– Program memory: 32 Kbytes Flash; dataretention:15 years at 85℃ after 10 kcycles at 25 ℃

　　– Data memory: 1 Kbyte true data EEPROM;data retention: 15 years at 85℃ after 100

　　kcycles at 85℃

　　– RAM: 6 Kbytes

　　 Transmitter reference design:

　　– Evaluation board order code:

　　STEVAL-ISB038V1T

　　– 2-layer PCBs

　　– Active object detection

　　– Graphical user interface for applicationmonitoring

　　– Interoperable with receiver:

　　STEVAL-ISB038V1R

　　 Operating temperature

　　– -40℃ up to 105℃

　　 Package

　　– VFQFPN32

　　图1.无线充电系统架构图

　　图2.STWBC-WA无线功率发送器框图

　　基于Qi 的1 W无线功率接收器STWLC04

　　The STWLC04 is an integrated wireless power receiver suitable for wearable applications. The device is designed for 1-watt power transfer based on the Qi protocol, with digital control and precise analog control loops ensuring stable operation. The I2C interface allows a high degree of customization and settings can be stored in the embedded non-volatile memory.

　　The STWLC04 can deliver the output power in two modes: as a power supply with configured output voltage or as a simple CC/CV battery charger with configurable charging current, charging voltage and termination current. The STWLC04 can detect the external (wired) power supply connection and drive an external power switch.

　　The STWLC04 is an advanced, integrated receiver IC for wireless power transceiver in wearable applications optimized for 1 W. It works as a voltage source with regulated output voltage, typically 5 V and can also be reconfigured into a simple battery charger mode (CC/CV) to charge directly Li-Ion or Li-pol batteries. The STWLC04 can operate fully autonomously or can be controlled through I2C by the host system.

　　STWLC04主要特性:

　　 1 W output power

　　 Qi 1.1 wireless standard communication protocol based

　　 Integrated high efficiency synchronous rectifier

　　 800 kHz programmable step-down converter with input current and input voltage regulation loop

　　 Step-down converter efficiency up to 90%

　　 Simplified Li-Ion/Polymer charger function

　　 32-bit, 16 MHz embedded microcontroller with 16 kB ROM and 2 kB RAM memory  2 kB NVM for customization

　　 Integrated driver for external supply switch

　　 Precise voltage and current measurements for received power calculation

　　 I2C interface

　　 Configurable GPIO output

　　 Rx coil NTC protection

　　 Thermal protection

　　 Low power dissipative rectifier overvoltage clamp

　　 Flip Chip 77 bumps (3.12x4.73 mm)

　　STWLC04应用:

　　 Wearable applications

　　 Smart watches

　　 Glasses

　　 Medical and healthcare instrumentation

　　图3.STWLC04框图

　　图4.STWLC04应用电路图

　　采用STWBC-WA和STWLC04的1W可穿戴无线电源系统STEVAL-ISB038V1

　　The STEVAL-ISB038V1 is a wireless battery charger evaluation kit designed for ultra-compact battery operated devices, such as wearable gears, smartwatches, Internet Of Things sensors, medical devices.

　　The kit supports wireless power transfer of 1 Watt over a 11 mm coil on the receiver side and 20 mm on transmitter side. The kit configuration delivers 1 Watt of power at the receiver side.

　　The Kit is configured to support low power (1 W) applications. The Kit can support up to 3 W applications by means of wider coils or by switching to full-bridge configuration on the transmitters (documentation available on KIT webpage on www.st.com).

　　The STWBC-WA transmitter is based on a cost-effective half bridge topologies (full-bridge optional) offers flexibility in terms of offering a powerful software API which allows to modify the behaviour of LED and GPIOs, as well as adding external interfaces via I²C and UART communication ports.

　　The STWLC04 is focused on 1 W protocol based on Qi.Digital control and precise analog control loops assure stable operation. I²C interface allows many parameters to be customized in the device and this configuration can be stored in the embedded NVM memory.

　　The STWLC04 receiver can deliver the output power in the following modes:

　　1. as a power supply with configured output voltage

　　2. as a CC/CV battery charger with configurable charging current and voltage.

　　The full kit includes the STWBC-WA demo board; the STWLC04 demo board; the graphical interface to monitor the transmitter behavior; schematics, layout files and bill of materials.

　　Tools for the STEVAL-ISB038V1 are available on www.st.com for users to access runtime information such as delivered power and protocol status, and to adjust certain parameters.

　　图5.1W可穿戴无线电源系统STEVAL-ISB038V1外形图

　　1W可穿戴无线电源系统STEVAL-ISB038V主要特性:

　　Wearable KIT characteristics:

　　11 mm coil on Receiver

　　20 mm coil on Transmitter

　　1 Watt delivered on Receiver side

　　USB 5 V input

　　Foreign Object Detection (FOD) optional

　　Graphical interface for monitoring behavior

　　Total reference design

　　RoHS compliant

　　STWBC-WA Wireless power transmitter:

　　Cost effective Half Bridge topology with integrated drivers

　　Optional Full Bridge configuration for 3 W applications

　　Active presence detector

　　2-layer PCB to facilitate design

　　Turnkey solution or customizable via APIs

　　Parametric customization via Graphical interface

　　STEVAL-ISB038V1T发送板材料清单:

　　STEVAL-ISB038V1T接收板材料清单: