SLUSB20C November   2012  – November 2021

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1  Absolute Maximum Ratings
    2. 7.2  ESD Ratings
    3. 7.3  Recommended Operating Conditions
    4. 7.4  Thermal Information
    5. 7.5  Electrical Characteristics: Supply Current
    6. 7.6  Digital Input and Output DC Characteristics
    7. 7.7  Power-on Reset
    8. 7.8  2.5-V LDO Regulator
    9. 7.9  Internal Clock Oscillators
    10. 7.10 ADC (Temperature and Cell Measurement) Characteristics
    11. 7.11 Integrating ADC (Coulomb Counter) Characteristics
    12. 7.12 Data Flash Memory Characteristics
    13. 7.13 I2C-Compatible Interface Communication Timing Requirements
    14. 7.14 Typical Characteristics
  8. 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 Power Modes
        1. 8.4.1.1 BAT INSERT CHECK Mode
        2. 8.4.1.2 NORMAL Mode
        3. 8.4.1.3 SLEEP Mode
      2. 8.4.2 SLEEP+ Mode
      3. 8.4.3 HIBERNATE Mode
    5. 8.5 Programming
      1. 8.5.1 Standard Data Commands
      2. 8.5.2 Extended Data Commands
      3. 8.5.3 Communications
        1. 8.5.3.1 I2C Interface
        2. 8.5.3.2 I2C Time Out
        3. 8.5.3.3 I2C Command Waiting Time
        4. 8.5.3.4 I2C Clock Stretching
  9. 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
        1. 9.2.2.1 BAT Voltage Sense Input
        2. 9.2.2.2 SRP and SRN Current Sense Inputs
        3. 9.2.2.3 Sense Resistor Selection
        4. 9.2.2.4 TS Temperature Sense Input
        5. 9.2.2.5 Thermistor Selection
        6. 9.2.2.6 REGIN Power Supply Input Filtering
        7. 9.2.2.7 VCC LDO Output Filtering
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
    1. 10.1 Power Supply Decoupling
  11. 11Layout
    1. 11.1 Layout Guidelines
      1. 11.1.1 Sense Resistor Connections
      2. 11.1.2 Thermistor Connections
      3. 11.1.3 High-Current and Low-Current Path Separation
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Third-Party Products Disclaimer
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Receiving Notification of Documentation Updates
    4. 12.4 Support Resources
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

8.5.3.4 I2C Clock Stretching

A clock stretch can occur during all modes of fuel gauge operation. In SLEEP and HIBERNATE modes, a short clock stretch occurs on all I2C traffic as the device must wake-up to process the packet. In the other modes (BAT INSERT CHECK, NORMAL, SNOOZE) clock stretching only occurs for packets addressed for the fuel gauge. The majority of clock stretch periods are small as the I2C interface performs normal data flow control. However, less frequent yet more significant clock stretch periods may occur as blocks of Data Flash are updated. The following table summarizes the approximate clock stretch duration for various fuel gauge operating conditions.

Table 8-3 Approximate Clock Stretch Duration
GAUGING MODEOPERATING CONDITION or COMMENTAPPROXIMATE
DURATION
SLEEP
HIBERNATE		 Clock stretch occurs at the beginning of all traffic as the device wakes up. 5 ms
BAT INSERT CHECK,
NORMAL,
SNOOZE		 Clock stretch occurs within the packet for flow control (after a start bit, ACK or first data bit). 100 µs
Normal Ra table Data Flash updates. 24 ms
Data Flash block writes. 72 ms
Restored Data Flash block write after loss of power. 116 ms
End of discharge Ra table Data Flash update. 144 ms