1. Wireless Power: The Qi standard and bqTESLATM Solutions

2. Wireless power technologies
TI, Philips, Fulton, Convenient Power, Sanyo and more
Conductive Charging
(Wildcharge, Duracell)
Wireless Power Consortium
Palm, Powermat
Toothbrush, Witricity
RF Wireless Power (Powercast) 2

3. Wireless Power Consortium (WPC)
WPC is the only industry standard that has released a specification for low power applications (<5W).
Currently there are 80+ members from various segments of the industry.
The standard aims to enable interoperability between various charging pads and portable devices.
All compatible devices will be
marked with a Qi logo.
The WPC is now working
towards a specification for medium
power (up to 125W). 3

4. TI and WPC
As members of the steering and specification work groups, TI is actively involved in setting the industry standard and the vision of WPC.
In addition, we are also actively involved in the promotional, logo & licensing and regulatory work groups.
TI has also established successful partnerships with various members to accelerate the adoption of WPC solutions into market and solve the technical challenges associated with this technology. 4

5. Wireless Power Consortium – Members (80+)
A short list of members shown
WPC V1.0
Low power specification
is now available for download

6. Market TAM forecast  standardization / interoperability will drive growth6

7. Typical inductive power system
AC to DC
Drivers
Rectification
Voltage
Conditioning
Load
Communication
Controller
V/I
Sense
Controller
Transmitter
Receiver

8. System overview Power transmitted through shared magnetic field.
Transmit coil creates magnetic field.
Receive coil in proximity converts field into current.
Shielding material on each side directs field to reduce stray field, increase efficiency, and increase positional freedom.
Power transferred only when needed.
Transmitter waits until its field has been perturbed.
Transmitter sends seek energy and waits for a digital response.
If response is valid, power transfer begins.
Power transferred only at level needed.
Receiver constantly monitors power received and delivered.
Transmitter adjusts power sent based on receiver feedback.
If feedback is lost, power transfer stops.

9. Basics of inductive power transfer
Inductive power transfer works by coupling a magnetic field from primary to secondary.
Uncoupled field lines rotate around primary coil, don’t represent loss as long as the field lines don’t couple a parasitic load (eddy current loss).
Reasonable efficiency can be achieved when the z-gap is less than the coil diameter.
dB/dt I
z < D D

10. Efficiency dependencies
8 January 2010
Distance (z) between coils
Ratio of diameters (D2 / D) of the two coils
Q-factor (ratio of the inductance L to the resistance R) 10

11. Efficiency is good when coils are less than one diameter apart
8 January 2010
Qi operating distance
40% at 1 diameter
1% at 2.5 diameter
0.1% at 4 diameters
0.01% at 6 diameters
16 September 2018 11

12. Communication - Basics
Primary side controller must detect that an object is placed on the charging pad.
When a load is placed on the pad, the primary coil effective impedance changes.
“Analog ping” occurs to detect the device.
After an object is detected, must validate that it is WPC-compatible receiver device.
“Digital Ping” – transmitter sends a longer packet which powers up the RX side controller.
RX side controller responds with signal strength indicator packet.
TX controller will send multiple digital pings corresponding to each possible primary coil to identify best positioning of the RX device.
After object is detected and validated, Power Transfer phase begins.
RX will send Control Error Packets to increase or decrease power level.
WPC Compliant protocol ensures interoperability.

13. Transmitter Receiver Power Pickup Unit Cs Cd C Ls Load
Secondary coil (Ls)
Serial resonance capacitor (Cs) for efficient power transfer
Parallel resonance capacitor (Cd) for detection purposes
Rectifier: full bridge (diode, or switched) + capacitor
Output switch for (dis-)connecting the load
Primary coil (Lp) + serial resonance capacitor (Cp)
Inverter: e.g. half bridge
Controlled by e.g. frequency or voltage
Power Pickup Unit Ls Cs Cd C
Load 13

14. Communication (Modulation)
Receiver modulates load by
Switching modulation resistor (Rm), or
Switching modulation capacitor (Cm)
Transmitter de-modulates reflected load by
Sensing primary coil current (Ip) and/or
Sensing primary coil voltage (Vp)
Transmitter
Receiver
Modulation Cm Cp Lp Rm
Modulation Cs + - Vp
Data Cd C Ip Ls
Power

15. Communication
VOUT, IOUT
Control processor on RX side will apply load pulses for signaling back to TX.
Load current is sensed on primary side – demodulated to get signaling data. 15

16. Switching Frequency Variation
System operates near resonance for improved efficiency.
Power control by changing the frequency, moving along the resonance curve.
Modulation using the power transfer coils establishes the communications.
Feedback is transferred to the primary as error.
80 KHz
100 KHz
120 KHz

17. WPC version 1.0 TX design freedom
Guided Positioning
(Magnetic Attraction)
Tactical feedback or free positioning
Alignment or selection of coils
Activation after detection M
Free Positioning (Coil Array)
Free Positioning (Coil Array) A
Free Positioning
(Moving Coil) y
The standard allows different types of transmitters.
Show animation! x
16 September 2018 17

18. bqTESLA150LP Evaluation Kit18

19. WPC Compliant Receiver Coil
Qi-compliant RX coil used w/ EVM kit
40-mm x 30-mm x 0.75-mm
WPC Compliant Receiver Coil 19

20. bq51013 “form factor” demo PCB
5-mm x 15-mm footprint for all RX side circuitry - Represents what an OEM would design into their actual end-product to enable wireless power from a QI-compliant charging pad. 20

21. bqTESLATM Chipset Two WPC Compliant solutions
bqTESLA100LP : Based on discrete components (Gen1)
bqTESLA150LP: Based on integrated single chip bq51013 receiver solution that optimizes performance, size, and cost (Gen2)
Solutions focused on WPC V1.0 Low Power Standard

22. bqTESLA100LP: TI’s First Qi-Compliant Solution
Power
bq25046
AC to DC
Rectification
Drivers
Voltage
Conditioning
Load
Communication
Controller
V/I
Sense
Controller
MSP430bq1010
bq500110
Transmitter
Receiver

23. bq500110RGZ WP Gen 1 Transmitter (Tx) Controller
Benefits
Features
Complete Contactless Charging solution when coupled with receiver solutions (Rx) bq2504x and Mbq
Low-cost driver implementation
Enables LED charge status indicators
Conforms to wireless power transfer protocol
Delivers comprehensive system-level power transfer management
Safe Operation
Variety of indication schemes
Single-bay Contactless Charger
Half-bridge NFET power stage
3 Digital I/O Pins
Receiver-driven communication protocol
PID closed-loop voltage regulation via frequency modulation (100kHz-200kHz)
High efficiency (72.5% at 5W; 70% at 2.5W)
Thermal Shutdown and Parasitic Loss Detection
14 programmed LED indication schemes
7x7 48 pin QFN Package (Pb Free, RoHS Compliant)
Applications
Transmitter Pad for Contactless Charging
Targeted for low-power (<5W) end equipments: cell phones, digital cameras, portable media players, remote/gaming controllers, Bluetooth headsets and other portable devices
EVM/Tool
bq500110EVM-HPA688EVM 23

24. EMI Considerations CISPR22 Not Intended Transmissions
Not Optimized EVM
Improved TI EVM

25. Rx – bq25046 Power Supply Solution

26. bq25046: 1.5A,Single-Input, Wireless Receiver Power Supply with 15mA LDO
Features
30V input rating, with 15V Over-Voltage Protection (OVP) threshold
Integrated charge current sense for contactless power transfer efficiency monitoring
3.3V, 15mA integrated low dropout linear regulator (VDD3.3) supplies power to MSP430bq1010 directly
2% Output Voltage Regulation
Pin selectable 100mA and 500mA current limit enables robust communication at any output current level
Soft-Start feature to reduce inrush current
Status Indication – Power Good (/PG) and Output Enabled (/CHG)
Available in small 2mm x 3mm DFN-10 package

27. MSP430bq1010: Wireless Power Rx Communication Control IC
Enables contactless power solution
Communication & voltage/current monitoring
Optional contactless power transfer termination
Fixed function device - No software development required
5.0 x 5.0 x 0.75mm 32-pin RTV (QFN) package

28. bqTESLA150LP: Gen 2 Solution bq51013 RX

29. New Ways to Power & Charge Your Device
Battery Charger
Before
Now
bqTESLA150LP
Tx: bq500110
Rx: bq51013
(1/5th the Area of bqTESLA100LP Rx)
19V 5V
System/Battery

30. bqTESLA150LP: Receiver Integration 80% PCB Area Savings vs ‘100LP
Power
bq51013
AC to DC
Rectification
Drivers
Voltage
Conditioning
Load
Communication
Controller
V/I
Sense
Controller
bq500110
Transmitter
Receiver

31. Rx Products and Roadmap
BOM Count: 20
15mm
BOM Count: 52
5mm
Z: 1.5mm
bq5101x
In development…
PERFORMANCE
bq51013
WPC-compliant
Fully integrated solution.
Prototype development, Evalu Kit released
22mm
16mm
Z: 1.68mm
bq25046, MSP430BQ1010
WPC Compliant Solution
Prototype development, Eval Kit released
Learning tool for customers
Planned Release
04/18/11
RTM
Released!
Development
TIME
Dec’10
Apr’11 31 31

32. bq51013 – General 5V Power Supply
bq51013 automatically selects between AC and wireless input power
When wireless power is active, IC communicates with the primary to regulate the secondary voltage to 5V.
bq51013 acts as a Power Supply to deliver 5-V to the VIN pin of the system charger

33. bq51013 Gen 2.0 Wireless Power Receiver (RX) – WPC Compliant
Benefits
Features
Integration reduces total system solution board space and cost
- Provides more power to end equipment and reduces heat dissipation
- Integration into single devices simplifies design and reduces board space
- Allows RX to have interoperability with WPC compliant TX solutions
- Output regulation provides quiet output voltage ready for load
- Simplifies design and reduces board space and cost.
Consistent power delivered to system load to reduced power sags
Provides broad range of applications and coils
Protects the IC from voltages beyond the maximum rating of the IC
Prevents potential damage device and lowers power dissipation
Optimal Safety and reduces I/O required to Host
Saves board space and offers alternate packaging for manufacturing
Integrated Wireless Power Receiver Solution with a 5V Regulated Supply
- 93% Overall Peak AC-DC Efficiency
- Full Synchronous Rectifier
- WPC v1.0 Compliant Communication Control
- Output Voltage Conditioning
- Only IC Required Between RX coil and 5V DC Output Voltage
Internal Dynamic Rectifier Control for Improved Load Transient Response
Supports 20V Max Input
Low-power Dissipative Rectifier Overvoltage Clamp (VOVP = 15V)
Thermal Shutdown
Single NTC/Control
1.9 x 3mm WCSP or 4.5 x 3.5mm QFN Package
Applications
Targeted for low-power (<5W) end equipment: Cell phones - Digital cameras - Portable media players - Remote/gaming controllers - Bluetooth, Headsets - Other portable devices
EVM Tool
bq51013EVM 33 33

34. For technical specs & tutorials: