SLUSFU9 October   2024 BQ51013C

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Description (continued)
  6. 5 Device Comparison Table
  7. 6 Pin Configuration and Functions
  8. 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
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Details of a Qi Wireless Power System and BQ51013C 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 v2.0 Compliance – Foreign Object Detection
      17. 8.3.17 Receiver Coil Load-Line Analysis
    4. 8.4 Device Functional Modes
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 BQ51013C Wireless Power Receiver Used as a Power Supply
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Using The BQ51013C as a Wireless Power Supply: (See Figure 1-1 )
          2. 9.2.1.2.2 Series and Parallel Resonant Capacitor Selection
          3. 9.2.1.2.3 Recommended RX Coils
          4. 9.2.1.2.4 COMM, CLAMP, and BOOT Capacitors
          5. 9.2.1.2.5 Control Pins and CHG
          6. 9.2.1.2.6 Current Limit and FOD
          7. 9.2.1.2.7 RECT and OUT Capacitance
        3. 9.2.1.3 Application Curves
      2. 9.2.2 Dual Power Path: Wireless Power and DC Input
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
        3. 9.2.2.3 Application Curves
      3. 9.2.3 Wireless and Direct Charging of a Li-Ion Battery at 800 mA
        1. 9.2.3.1 Design Requirements
        2. 9.2.3.2 Detailed Design Procedure
        3. 9.2.3.3 Application Curves
  11. 10Power Supply Recommendations
  12. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  13. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Third-Party Products Disclaimer
      2. 12.1.2 Development Support
    2. 12.2 Receiving Notification of Documentation Updates
    3. 12.3 Support Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  14. 13Revision History
  15. 14Mechanical, Packaging, and Orderable Information

8.3.4 RILIM Calculations

The BQ51013C includes a means of providing hardware overcurrent protection by means of an analog current regulation loop. The hardware current limit provides an extra level of safety by clamping the maximum allowable output current (current compliance). The RILIM resistor size also sets the thresholds for the dynamic rectifier levels and thus providing efficiency tuning per each application’s maximum system current. The calculation for the total RILIM resistance is as follows:

Equation 2. BQ51013C

where

  • IMAX is the expected maximum output current during normal operation.
  • IILIM is the hardware over current limit.

When referring to the application diagram shown in Figure 9-1, RILIM is the sum of RFOD and R1 (the total resistance from the ILIM pin to GND).