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

7.3.1.3 VSET Pin Detection

VSET pin is used to program the device regulation voltage at end-of-charge using a ±1% pulldown resistor. The available pulldown resistor and corresponding charging levels are:

Table 7-2 VSET Pin Resistor Value Table
RESISTOR Li+ CONFIGURATION NiMH CONFIGURATION
CHARGE VOLTAGE (V) CELL COUNT
> 150 kΩ No charge (open-circuit) No charge (open-circuit)
100 kΩ 1-cell LiFePO4: 3.50 V No charge (open-circuit)
82 kΩ 1-cell LiFePO4: 3.60 V No charge (open-circuit)
62 kΩ 1-cell LiFePO4: 3.70 V 1-cell
47 kΩ 1-cell LiIon: 3.80 V 1-cell + intermittent charge
36 kΩ 1-cell LiIon: 3.90 V 2-cell
27 kΩ 1-cell LiIon: 4.05 V 2-cell + intermittent charge
24 kΩ 1-cell LiIon: 4.10 V 3-cell
18 kΩ 1-cell LiIon: 4.20 V 3-cell + intermittent charge
15 kΩ 1-cell LiIon: 4.35 V 4-cell
11 kΩ 2-cell LiFePO4: 7.00 V 4-cell + intermittent charge
8.2 kΩ 2-cell LiFePO4: 7.20 V 5-cell
6.2 kΩ 2-cell LiFePO4: 7.40 V 5-cell + intermittent charge
4.7 kΩ 2-cell LiIon: 8.20 V 6-cell
3.6 kΩ 2-cell LiIon: 8.40 V 6-cell + intermittent charge
< 3.0 kΩ No charge (short-circuit) No charge (short-circuit)

If either a short- or open-circuit condition is detected, charger stops operation and remains in the FAULT state until the input or CE pin is toggled.

Once a valid resistor value has been detected, the corresponding charge voltage is latched in and the pin is not continuously monitored during operation. A change in this pin will not be acknowledged by the IC until the input supply or CE pin is toggled.