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
9.2.1.2.5 Control Pins and CHG

This section discusses the pins that control the functions of the BQ51013C (AD, AD_EN, EN1, EN2, and TS/CTRL).

This solution uses wireless power exclusively. The AD pin is tied low to disable wired power interaction. The output pin AD_EN is left floating.

EN1 and EN2 are tied to the system controller GPIO pins. This allows the system to control the wireless power transfer. Normal operation leaves EN1 and EN2 low or floating (GPIO low or high impedance). EN1 and EN2 have internal pulldown resistors. With both EN1 and EN2 low, wireless power is enabled and power can be transferred whenever the RX is on a suitable TX. The RX system controller can terminate power transfer and send an EPT 0x01 (Charge Complete) by setting EN1=EN2=1. The TX will terminate power when the EPT 0x01 is received. The TX will continue to test for power transfer, but will not engage until the RX requests power. For example, if the TX is the BQ500212A, the TX will send digital pings approximately once per 5 seconds. During each ping, the BQ51013C will resend the EPT 0x01. Between the pings, the BQ500212A goes into low power "Sleep" mode reducing power consumption. When the RX system controller determines it is time to resume power transfer (for example, the battery voltage is below its recharge threshold) the controller simply returns EN1 and EN2 to low (or float) states. The next ping of the BQ500212A will power the BQ51013C which will now communicate that it is time to transfer power. The TX and RX communication resumes and power transfer is reinitiated.

The TS/CTRL pin will be used as a temperature sensor (with the NTC) and maintain the ability to terminate power transfer through the system controller. In this case, the GPIO will be in high impedance for normal NTC (Temperature Sense) control.

The CHG pin is used to indicate power transfer. A 2.1V forward bias LED is used for D1 with a current limiting 1.5kΩ series resistor. The LED and resistor are tied from OUT to PGND and D1 will light during power transfer.