Power (W)

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

5%

10%

15%

20%

25%

30%

35%

40%

45%

50%

55%

60%

65%

70%

75%

80%

D001

bq50002A

bq500511A

TRANSMITTER

RECEIVER

Rectification

Voltage

Conditioning

Load

Controller

bq51k

Communication

Power

5 V

Input

3 V

PWM

Control

Feedback

Copyright © 2016, Texas Instruments Incorporated

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An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications,

intellectual property matters and other important disclaimers. PRODUCTION DATA.

bq50002A

SLUSCP1A – AUGUST 2016 – REVISED AUGUST 2016

bq50002A Low-Cost 5-V Wireless Power Transmitter Analog Front End

for WPC v1.2 A11 Transmitters

1

1 Features

1

•

5-V Transmitter AFE Compatible With Wireless

Power Consortium (WPC) v1.2 A11 Low-Power

Transmitter Specification

•

Designed to be Used With bq500511A WPC

Controller

–

Note: The bq50002A is Incompatible With the

bq500511 Device if Foreign Object Detection

is Required

•

Suitable for WPC and Proprietary 5-V Wireless

Power Transmitters

•

Supports 5 W on the Receiver Output

•

Integrates All the Analog Functions Required in a

Wireless Power Transmitter

–

MOSFET Drivers and Synchronous N-Channel

Power FETs

–

Accurate Current Sense

–

Variable Frequency Oscillator

–

High-Efficiency Voltage Regulator

–

High-Sensitivity Demodulator to Decode

Signals From Receiver

•

2-Chip Solution Enables High-Efficiency

Transmitter Designs of >75% Efficiency

•

Ultra-Low-Standby Power, Even During Digital

Ping (<30 mW)

•

Dynamic Power Limiting (DPL)™ Enables

Operation From Input Sources With Limited Power

•

System LED Indication of Charging State and

Fault Status

•

Accurate Foreign Object Detection Method (FOD)

2 Applications

•

WPC Compliant Wireless Transmitters for Smart

Phones and Wearable Applications

•

Proprietary Wireless Chargers and Transmitters

•

Medical and Wearable Applications

3 Description

The bq50002A device is a highly integrated wireless

power

transmitter

analog

front

end

(AFE)

that

contains all of the analog components required to

implement a Wireless Power Consortium (WPC)

compliant 5-V transmitter. The bq50002A device

integrates a full-bridge power driver with MOSFETs,

variable-frequency

oscillator,

two-channel

communication demodulator, linear regulator, and

protection circuits. The bq50002A device must be

used together with the digital controller bq500511A to

realize a compact two chip wireless power transmitter

solution. The bq500511A safely engages the RX

device, receives packet communication from the

powered device, and manages the power transfer

according to WPC v1.2 specification.

The system supports foreign object detection (FOD)

by continuously monitoring the amount of power

transferred and comparing that to the amount of

received power, as reported by the receiver. This

protects

against

power

loss

to

metal

objects

misplaced in the wireless power transfer field. To do

this, the bq50002A measures the input DC current

accurately by using a current sense amplifier. Should

any

abnormal

condition

develop

during

power

transfer, the bq500511A handles it and provides

indication outputs. Comprehensive status and fault

monitoring features enable a low cost yet robust

WPC-certified wireless power system design.

The bq50002A is available in a thermally enhanced

5.00 mm × 5.00 mm, 32-pin QFN package.

Device Information (1)

PART NUMBER

PACKAGE

BODY SIZE (NOM)

bq50002A

QFN (32)

5.00 mm × 5.00 mm

(1) For all available packages, see the orderable addendum at

the end of the data sheet.

Simplified Schematic

Efficiency vs Power