SLUSDK0A August   2020  – March 2021 BQ25171-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Timing Requirements
    7. 6.7 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Device Power Up from Input Source
        1. 7.3.1.1 ISET Pin Detection
        2. 7.3.1.2 CHM_TMR Pin Detection
        3. 7.3.1.3 VSET Pin Detection
        4. 7.3.1.4 Charger Power Up
      2. 7.3.2 Battery Charging Features
        1. 7.3.2.1 Lithium-Ion Battery Charging Profile
          1. 7.3.2.1.1 NiMH Battery Charging Profile
        2. 7.3.2.2 Charge Termination and Battery Recharge
        3. 7.3.2.3 Charging Safety Timers
        4. 7.3.2.4 Battery Cold, Hot Temperature Qualification (TS Pin)
      3. 7.3.3 Status Outputs (STAT1, STAT2)
        1. 7.3.3.1 Charging Status Indicator (STAT1, STAT2)
      4. 7.3.4 Protection Features
        1. 7.3.4.1 Input Overvoltage Protection (VIN OVP)
        2. 7.3.4.2 Output Overvoltage Protection (BAT OVP)
        3. 7.3.4.3 Output Overcurrent Protection (BAT OCP)
        4. 7.3.4.4 Thermal Regulation and Thermal Shutdown (TREG and TSHUT)
    4. 7.4 Device Functional Modes
      1. 7.4.1 Shutdown or Undervoltage Lockout (UVLO)
      2. 7.4.2 Sleep Mode
      3. 7.4.3 Active Mode
        1. 7.4.3.1 Standby Mode
      4. 7.4.4 Fault Mode
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 1s LiFePO4 Charger Design Example
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Program the Fast Charge Current, ISET:
          2. 8.2.1.2.2 TS Function
        3. 8.2.1.3 Application Curves
      2. 8.2.2 2s Li-Ion Charger with Power Path Design Example
        1. 8.2.2.1 Design Requirements
      3. 8.2.3 4s NiMH Charger Design Example
        1. 8.2.3.1 Design Requirements
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

7.3.2.4 Battery Cold, Hot Temperature Qualification (TS Pin)

While charging, the device continuously monitors battery temperature by sensing the voltage at the TS pin. A negative temperature coefficient (NTC) thermistor should be connected between the TS and GND pins (recommend: 103AT-2). If temperature sensing is not required in the application, connect a fixed 10-kΩ resistor from TS to GND to allow normal operation. Battery charging is allowed when the TS pin voltage falls between VCOLD and VHOT thresholds (typically 0°C – 45°C). The temperature corresponding to these voltage thresholds can be modified by adding resistors in parallel and in series with the thermistor, as shown in Figure 7-6. If the TS pin indicates battery temperature is outside this range, the device stops charging, enters the STANDBY state, and sets the STAT pins to STAT1 = LOW , STAT2 = HIGH to indicate a recoverable fault. Once battery temperature returns to normal conditions, charging resumes automatically.

GUID-E99E37F6-D421-452C-BD10-79EF980A3767-low.gifFigure 7-6 TS Resistor Network For Modified Temperature Charging Window
Table 7-3 Recommended Resistor Values for Different Temperature Charging Windows
TEMPERATURE CHARGING WINDOW RS RP
0°C to 60°C 1.9 kΩ 400 kΩ
−10°C to 60°C 2.3 kΩ 70 kΩ
−10°C to 50°C 1.1 kΩ 70 kΩ