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

COMM, CLAMP, and BOOT Capacitors

For most applications, the COMM, CLAMP, and BOOT capacitance values will be chosen to match the bq51003EVM-764.

The BOOT capacitors are used to allow the internal rectifier FETs to turn on and off properly. These capacitors are from AC1 to BOOT1 and from AC2 to BOOT2 and must have a minimum 25-V rating. A 10-nF capacitor with a 25-V rating is chosen.

The CLAMP capacitors are used to aid in the clamping process to protect against overvoltage. These capacitors are from AC1 to CLAMP1 and from AC2 to CLAMP2 and must have a minimum 25-V rating. A 0.47-µF capacitor with a 25-V rating is chosen.

The COMM capacitors are used to facilitate the communication from the RX to the TX. This selection can vary a bit more than the BOOT and CLAMP capacitors. In general, TI recommends an 22-nF capacitor. Based on the results of testing of the communication robustness in the final solution, a change to a 47-nF capacitor may be in order. The larger the capacitor the larger the deviation will be on the coil which sends a stronger signal to the TX. This also decreases the efficiency somewhat. In this case, a 22-nF capacitor with a 25-V rating is chosen.