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

7.3.1.2 CHM_TMR Pin Detection

CHM_TMR pin is used to program the device chemistry and safety timer using a ±1% pulldown resistor. The available pulldown resistor and corresponding behaviors are:

Table 7-1 CHM_TMR Pin Resistor Value Table
RESISTORCHEMISTRYCHARGE TIMER (HR)
> 150 kΩNo charge (open-circuit)No charge (open-circuit)
100 kΩLi+5 hr
82 kΩLi+10 hr
62 kΩLi+Timer disable
47 kΩNo charge (pin fault / margin)No charge (pin fault / margin)
36 kΩNiMH4 hr
27 kΩNiMH6 hr
24 kΩNiMH8 hr
18 kΩNiMH10 hr
15 kΩNiMH12 hr
11 kΩNiMH14 hr
8.2 kΩNiMH16 hr
6.2 kΩNiMH18 hr
4.7 kΩNiMH20 hr
3.6 kΩNiMH22 hr
< 3.0 kΩNo 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 value has been detected, it 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.