ST公司的STWBC-EP是Qi MP-A10 15 W無線電池充電發(fā)送器數(shù)字控制器,它為把功率傳送到WBC使能應(yīng)用的接收器(RX)提供了最靈活和有線的解決方案,VIN輸入范圍3V-5.5V,主要用在智能手機(jī),平板電腦以及其它以電池為能源和采用電磁感應(yīng)充電的設(shè)備.本文介紹了無線充電系統(tǒng)描述圖,STWBC-EP主要特性,架構(gòu)圖以及評估板STEVAL-ISB044V1主要特性,電路圖,材料清單和PCB設(shè)計圖.

The STWBC-EP is the digital controller for the wireless battery charger (WBC) transmitters(TX) from STMicroelectronics optimized for Extended Power Profile (EPP) Wireless PowerConsortium (WPC) 1.2 certified applications up to 15 W.

It offers the most flexible and efficient solution for controlling the power transfer to a receiver(RX) in WBC-enabled applications such as smartphones, tablets and other battery-powereddevices that use the electromagnetic induction for recharging.

The TX is responsible for controlling the transmitting coil and generating the correct amountof power requested by the RX. The RX continuously provides the transmitter with the correctpower level requested, by modulating the transmitter carrier through the controlled resistiveor capacitive load. Generating the correct amount of power ensures the highest level of end-to-end efficiency due to reduced energy losses. It also helps maintaining a lower operationaltemperature.

The TX can adapt to the amount of energy transferred by the coil by modulating thefrequency, duty cycle or amplitude of the PWM voltage on the transmitting coil.The STWBC-EP is capable of bidirectional communication with the RX as specified by theWPC 1.2 protocol.

STWBC-EP主要特性:

? Digital controller for wireless battery chargertransmitter
? 15 W single coil inductive transmittersoptimized for:
– Cell phones and smartphones
– Tablets and phablets
– Charging accessories
? Support for Wireless Power Consortium (WPC)1.2 EPP 15 W certified applications
– Backward compatible with 5 W WPC 1.1applications
? Support for half bridge topology with DC/DC
? VIN range: 3 V to 5.5 V
– Supports USB Vin
? Active presence detector
? Foreign object detection
? Q-factor measurement
? Parametric customization via GUI
? Turnkey firmware solution
? Peripherals
– 10-bit ADC
– UART interface
– I2C master fast/slow speed rate
– GPIOs
? Memory
– Flash and EEPROM with read-while-write(RWW) and Error Correction Code (ECC)
– Program memory: 32-Kbyte Flash; dataretention: 20 years at 55 ℃ after 1000
cycles at 55 ℃
– Data memory: 1 Kbyte true data EEPROM;
data retention: 20 years at 55℃ after 1000cycles at 85 ℃
– RAM: 6 Kbytes
? Transmitter reference design:
– WPC Qi 1.2.3 certified
– MP-A10 single coil 15 W topology
– Evaluation board order code: STEVALISB044V1
– 2-layer PCBs
– Active object detection
– Graphical User Interface for applicationmonitoring
? Operating temperature: -40℃ up to 105℃
? Package: VFQFPN32 - 5 x 5mm

圖1.無線充電系統(tǒng)描述圖

圖2.STWBC-EP架構(gòu)圖

評估板STEVAL-ISB044V1

Qi MP-A10 15 W wireless charger TX evaluation kit based on STWBC-EP
The STEVAL-ISB044V1 evaluation kit has been designed for devices, such as
smartphones or tablets, requiring high power levels.
It supports wireless battery charging up to 15 W.

The embedded STWBC-EP digital controller transmitter is based on a cost-effective half-bridge topology providing external interfaces via UART and I2C.The kit also includes STWBC-EP firmware, a graphical interface for debug,schematics, layout files and bill of materials.

There are specific tools for the STEVAL-ISB044V1 available on whichgive runtime information, such as the power delivered, the regulation error or theprotocol status as well as parameter tuning.

The STEVAL-ISB044V1 wireless power transmitter evaluation board is based on the MP-A10 (CR419) wireless power consortium (WPC) standard version 1.2.3 and supports FOD (foreign object detection).

The transmitter supports all Qi-compatible receivers (such as those in Qi- enabled mobile phones) as well as resistive or capacitive modulation receivers. In accordance with the Qi-MPA10 topology, the STEVAL-ISB044V1 supports a 5-13 V input voltage and a half-bridge stage with bridge voltage/frequency control.

The evaluation board is based on the STWBC- EP controller which integrates all the functions required to drive and monitor the transmitter, and controls the bridge voltage built in boost topology.

The STWBC-EP supports UART connectivity to a PC and, thanks to the STEVAL-ISB044V1 graphical interface, monitors the transmitter behavior in real-time.
The STEVAL-ISB044V1 reference design provides a complete kit which includes the STWBC-EP, firmware, layout based on cost- effective 2-layer PCB, graphical interfaces and tools.

評估板STEVAL-ISB044V1主要特性:

? STWBC-EP digital controller
? 15 W output power
? Qi MP-A10 reference design
? WPC Qi1.2.3 standard compliant
? Robust demodulation algorithm, with triple path (V, I, f)
? Foreign object detection (FOD)
? Accurate power control
? Active presence detection
? UART protocol to control and monitor the system
? Complete reference design (evaluation board, IC, firmware and tools)
? 2-layer PCB for easy design
? Flash memory-based
? RoHS compliant

圖3.評估板STEVAL-ISB044V1外形圖

圖4.評估板STEVAL-ISB044V1電路圖(1)

圖5.評估板STEVAL-ISB044V1電路圖(2)

圖6.評估板STEVAL-ISB044V1電路圖(3)

圖7.評估板STEVAL-ISB044V1電路圖(4)

圖8.評估板STEVAL-ISB044V1電路圖(5)

圖9.評估板STEVAL-ISB044V1電路圖(6)

圖10.評估板STEVAL-ISB044V1電路圖(7)

圖11.評估板STEVAL-ISB044V1電路圖(8)
評估板STEVAL-ISB044V1材料清單:

圖12.評估板STEVAL-ISB044V1 PCB設(shè)計圖:功能和區(qū)塊裝配

圖13.評估板STEVAL-ISB044V1 PCB設(shè)計圖:電源信號布線

圖14.評估板STEVAL-ISB044V1 PCB設(shè)計圖:地平面

圖15.評估板STEVAL-ISB044V1 PCB設(shè)計圖:DC/DC升壓走線

圖16.評估板STEVAL-ISB044V1 PCB設(shè)計圖:電源GND走線

圖17.評估板STEVAL-ISB044V1 PCB設(shè)計圖:橋接點(diǎn)走線

圖18.評估板STEVAL-ISB044V1 PCB設(shè)計圖:并聯(lián)電阻走線

圖19.評估板STEVAL-ISB044V1 PCB設(shè)計圖:EMI元件(1)

圖20.評估板STEVAL-ISB044V1 PCB設(shè)計圖:EMI元件(2)

圖21.評估板STEVAL-ISB044V1 PCB設(shè)計圖:STWBC-EP數(shù)字控制器布局

圖22.評估板STEVAL-ISB044V1 PCB設(shè)計圖:電流檢測

圖23.評估板STEVAL-ISB044V1 PCB設(shè)計圖:電流解調(diào)