SLUSD33A November   2017  – January 2021 BQ25122

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Description (continued)
  6. 6 Device Comparison Table
  7. 7 Pin Configuration and Functions
  8. 8 Specifications
    1. 8.1 Absolute Maximum Ratings
    2. 8.2 ESD Ratings
    3. 8.3 Recommended Operating Conditions
    4. 8.4 Thermal Information
    5. 8.5 Electrical Characteristics
    6. 8.6 Timing Requirements
    7. 8.7 Typical Characteristics
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1  Ship Mode
        1. 9.3.1.1 Ship Mode Entry and Exit
      2. 9.3.2  High Impedance Mode
      3. 9.3.3  Active Battery Only Connected
      4. 9.3.4  Voltage Based Battery Monitor
      5. 9.3.5  Sleep Mode
      6. 9.3.6  Input Voltage Based Dynamic Power Management (VIN(DPM))
      7. 9.3.7  Input Overvoltage Protection and Undervoltage Status Indication
      8. 9.3.8  Battery Charging Process and Charge Profile
      9. 9.3.9  Dynamic Power Path Management Mode
      10. 9.3.10 Battery Supplement Mode
      11. 9.3.11 Default Mode
      12. 9.3.12 Termination and Pre-Charge Current Programming by External Components (IPRETERM)
      13. 9.3.13 Input Current Limit Programming by External Components (ILIM)
      14. 9.3.14 Charge Current Programming by External Components (ISET)
      15. 9.3.15 Safety Timer and Watchdog Timer
      16. 9.3.16 External NTC Monitoring (TS)
      17. 9.3.17 Thermal Protection
      18. 9.3.18 Typical Application Power Dissipation
      19. 9.3.19 Status Indicators ( PG and INT)
      20. 9.3.20 Chip Disable ( CD)
      21. 9.3.21 Buck (PWM) Output
      22. 9.3.22 Load Switch / LDO Output and Control
      23. 9.3.23 Manual Reset Timer and Reset Output ( MR and RESET)
    4. 9.4 Device Functional Modes
    5. 9.5 Programming
      1. 9.5.1 Serial Interface Description
      2. 9.5.2 F/S Mode Protocol
    6. 9.6 Register Maps
      1. 9.6.1  Status and Ship Mode Control Register
      2. 9.6.2  Faults and Faults Mask Register
      3. 9.6.3  TS Control and Faults Masks Register
      4. 9.6.4  Fast Charge Control Register
      5. 9.6.5  Termination/Pre-Charge
      6. 9.6.6  Battery Voltage Control Register
      7. 9.6.7  SYS VOUT Control Register
      8. 9.6.8  Load Switch and LDO Control Register
      9. 9.6.9  Push-Button Control Register
      10. 9.6.10 ILIM and Battery UVLO Control Register
      11. 9.6.11 Voltage Based Battery Monitor Register
      12. 9.6.12 VIN_DPM and Timers Register
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 Default Settings
        2. 10.2.2.2 Choose the Correct Inductance and Capacitance
        3. 10.2.2.3 Calculations
          1. 10.2.2.3.1 Program the Fast Charge Current (ISET)
          2. 10.2.2.3.2 Program the Input Current Limit (ILIM)
          3. 10.2.2.3.3 Program the Pre-charge/termination Threshold (IPRETERM)
          4. 10.2.2.3.4 TS Resistors (TS)
      3. 10.2.3 Application Performance Curves
        1. 10.2.3.1 Charger Curves
        2. 10.2.3.2 SYS Output Curves
        3. 10.2.3.3 Load Switch and LDO Curves
        4. 10.2.3.4 LS/LDO Output Curves
        5. 10.2.3.5 Timing Waveforms Curves
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Device Support
      1. 13.1.1 Third-Party Products Disclaimer
    2. 13.2 Documentation Support
      1. 13.2.1 Related Documentation
    3. 13.3 Receiving Notification of Documentation Updates
    4. 13.4 Support Resources
    5. 13.5 Trademarks
    6. 13.6 Electrostatic Discharge Caution
    7. 13.7 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

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

9.5.1 Serial Interface Description

The device uses an I2C compatible interface to program and read many parameters. I2C is a 2-wire serial interface developed by NXP. The bus consists of a data line (SDA) and a clock line (SCL) with pull-up structures. When the bus is idle, both SDA and SCL lines are pulled high. All the I2C compatible devices connect to the I2C bus through open drain I/O terminals, SDA and SCL. A master device, usually a microcontroller or digital signal processor, controls the bus. The master is responsible for generating the SCL signal and device addresses. The master also generates specific conditions that indicate the START and STOP of data transfer. A slave device receives and/or transmits data on the bus under control of the master device.

The device works as a slave and supports the following data transfer modes, as defined in the I2C BUS Specification: standard mode (100 kbps) and fast mode (400kbps). The interface adds flexibility to the battery management solution, enabling most functions to be programmed to new values depending on the instantaneous application requirements. The I2C circuitry is powered from the battery in active battery mode. The battery voltage must stay above V(BATUVLO) when no VIN is present to maintain proper operation. The host must also wait for SYS to come up before starting communication with the part.

The data transfer protocol for standard and fast modes is exactly the same; therefore, they are referred to as the F/S-mode in this document. The device only supports 7-bit addressing. The device 7-bit address is 6A (8-bit shifted address is D4).

To avoid I2C hang-ups, a timer (tI2CRESET) runs duringI2C transactions. If the SDA line is held low longer than tI2CRESET, any additional commands are ignored and the I2C engine is reset. The timeout is reset with START and repeated START conditions and stops when a valid STOP condition is sent.