SLUSBU9I March   2014  – August 2024 BQ2970 , BQ2971 , BQ2972 , BQ2973

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
    1. 5.1 Pin Descriptions
      1. 5.1.1 Supply Input: BAT
      2. 5.1.2 Cell Negative Connection: VSS
      3. 5.1.3 Voltage Sense Node: V–
      4. 5.1.4 Discharge FET Gate Drive Output: DOUT
      5. 5.1.5 Charge FET Gate Drive Output: COUT
  7. 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 DC Characteristics
    6. 6.6 Programmable Fault Detection Thresholds
    7. 6.7 Programmable Fault Detection Timer Ranges
    8. 6.8 Typical Characteristics
  8. 7 Parameter Measurement Information
    1. 7.1 Timing Charts
    2. 7.2 Test Circuits
    3. 7.3 Test Circuit Diagrams
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
    4. 8.4 Device Functional Modes
      1. 8.4.1 Normal Operation
      2. 8.4.2 Overcharge Status
      3. 8.4.3 Over-Discharge Status
      4. 8.4.4 Discharge Overcurrent Status (Discharge Overcurrent, Load Short-Circuit)
      5. 8.4.5 Charge Overcurrent Status
      6. 8.4.6 0V Charging Function Enabled
      7. 8.4.7 0V Charging Inhibit Function
      8. 8.4.8 Delay Circuit
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Performance Plots
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Related Documentation
    2. 10.2 Support Resources
    3. 10.3 Trademarks
    4. 10.4 Electrostatic Discharge Caution
    5. 10.5 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

9.2.1 Design Requirements

For this design example, use the parameters listed in Table 9-1.

Table 9-1 Design Parameters
DESIGN PARAMETEREXAMPLE VALUE at TA = 25°C
Input voltage range4.5V to 7V
Maximum operating discharge current7A
Maximum Charge Current for battery pack4.5A
Overvoltage Protection (OVP)4.275V
Overvoltage detection delay timer1.2s
Overvoltage Protection (OVP) release voltage4.175V
Undervoltage Protection (UVP)2.8V
Undervoltage detection delay timer150ms
Undervoltage Protection (UVP) release voltage2.9V
Charge Overcurrent detection (OCC) voltage–70mV
Charge Overcurrent Detection (OCC) delay timer9ms
Discharge Overcurrent Detection (OCD) voltage100mV
Discharge Overcurrent Detection (OCD) delay timer18ms
Load Short Circuit Detection SCC) voltage, BAT to –V ≤ threshold500mV
Load Short Circuit Detection (SCC) delay timer250µs
Load Short Circuit release voltage, BAT to –V ≥ Threshold1V