SLUSBC8C December   2013  – July 2018


  1. Features
  2. Applications
  3. Description
    1.     Wireless Power Consortium (WPC or Qi) Inductive Power System
  4. Revision History
  5. Device Comparison Table
  6. Pin Configuration and Functions
    1.     Pin Functions
  7. Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Typical Characteristics
  8. Detailed Description
    1. 8.1 Overview
      1. 8.1.1 A Brief Description of the Wireless System
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Details of a Qi Wireless Power System and bq51003 Power Transfer Flow Diagrams
      2. 8.3.2  Dynamic Rectifier Control
      3. 8.3.3  Dynamic Efficiency Scaling
      4. 8.3.4  RILIM Calculations
      5. 8.3.5  Input Overvoltage
      6. 8.3.6  Adapter Enable Functionality and EN1/EN2 Control
      7. 8.3.7  End Power Transfer Packet (WPC Header 0x02)
      8. 8.3.8  Status Outputs
      9. 8.3.9  WPC Communication Scheme
      10. 8.3.10 Communication Modulator
      11. 8.3.11 Adaptive Communication Limit
      12. 8.3.12 Synchronous Rectification
      13. 8.3.13 Temperature Sense Resistor Network (TS)
      14. 8.3.14 3-State Driver Recommendations for the TS-CTRL Pin
      15. 8.3.15 Thermal Protection
      16. 8.3.16 WPC v1.2 Compliance – Foreign Object Detection
    4. 8.4 Device Functional Modes
  9. Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 bq51003 Wireless Power Receiver Used as a Power Supply
        1. Design Requirements
        2. Detailed Design Procedure
          1. Using the bq51003 as a Wireless Power Supply
          2. Series and Parallel Resonant Capacitor Selection
          3. COMM, CLAMP, and BOOT Capacitors
          4. Control Pins and CHG
          5. Current Limit and FOD
          6. RECT and OUT Capacitance
        3. Application Curves
      2. 9.2.2 Dual Power Path: Wireless Power and DC Input
        1. Design Requirements
        2. Detailed Design Procedure
        3. Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Development Support
    2. 12.2 Receiving Notification of Documentation Updates
    3. 12.3 Community Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

Pin Configuration and Functions

YFP Package
28-Pin DSBGA
Top View

Pin Functions

B3, B4 AC1 I AC input from receiver coil antenna.
B1, B2 AC2 I
G4 AD I Connect this pin to the wired adapter input. When a voltage is applied to this pin wireless charging is disabled and AD_EN is driven low. Connect to GND through a 1 µF capacitor. If unused, capacitor is not required and should be grounded directly.
F3 AD-EN O Push-pull driver for external PFET connecting AD and OUT. This node is pulled to the higher of OUT and AD when turning off the external FET. This voltage tracks approximately 4 V below AD when voltage is present at AD and provides a regulated VGS bias for the external FET. Float this pin if unused.
C4 BOOT1 O Bootstrap capacitors for driving the high-side FETs of the synchronous rectifier. Connect a 10 nF ceramic capacitor from BOOT1 to AC1 and from BOOT2 to AC2.
F4 CHG O Open-drain output – Active when the output of the wireless power supply is enabled.
E2 CLAMP2 O Open drain FETs which are utilized for a non-power dissipative over-voltage AC clamp protection. When the RECT voltage goes above 15 V, both switches will be turned on and the capacitors will act as a low impedance to protect the IC from damage. If used, CLAMP1 is required to be connected to AC1, and CLAMP2 is required to be connected to AC2 through 0.47-µF capacitors.
E4 COMM1 O Open-drain output used to communicate with primary by varying reflected impedance. Connect COMM1 through a capacitor to either AC1 or AC2 for capacitive load modulation (COMM2 must be connected to the alternate AC1 or AC2 pin). For resistive modulation connect COMM1 and COMM2 to RECT through a single resistor; connect through separate capacitors for capacitive load modulation.
G3 EN1 I Inputs that allow user to enable/disable wireless and wired charging <EN1 EN2>:
<00> Wireless charging is enabled
<01> Dynamic communication current limit disabled
<10> Wireless charging disabled
<11> Wireless charging disabled.
G2 EN2 I
F2 FOD I Input for the recieved power measurement. Connect to GND with a RFOD resistor.
G1 ILIM I/O Programming pin for the over current limit. Connect external resistor to VSS. Size RILIM with the following equation: RILIM = 262 / IMAX where IMAX is the expected maximum output current of the wireless power supply. The hardware current limit (IILIM) will be 20% greater than IMAX or 1.2 x IMAX. If the supply is meant to operate in current limit use
D1, D2, D3, D4 OUT O Output pin, delivers power to the load.
A1, A2, A3, A4 PGND Power ground
C2, C3 RECT O Filter capacitor for the internal synchronous rectifier. Connect a ceramic capacitor to PGND. Depending on the power levels, the value may be 4.7 μF to 22 μF.
F1 TS-CTRL I Must be connected to ground through a resistor. If an NTC function is not desired connect to GND with a 10-kΩ resistor. As a CTRL pin pull to ground to send end power transfer (EPT) fault to the transmitter or pullup to an internal rail (i.e. 1.8 V) to send EPT termination to the transmitter. Note that a 3-state driver should be used to interface this pin (see 3-State Driver Recommendations for the TS-CTRL Pin for further description).