SLUSBK2I October   2013  – March 2022 BQ76920 , BQ76930 , BQ76940

PRODMIX  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
    1. 6.1 Versions
    2. 6.2 BQ76920 Pin Diagram
    3. 6.3 BQ76930 Pin Diagram
    4. 6.4 BQ76940 Pin Diagram
  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
    6. 7.6 Timing Requirements
    7. 7.7 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Subsystems
        1. 8.3.1.1 Measurement Subsystem Overview
          1. 8.3.1.1.1 Data Transfer to the Host Controller
          2. 8.3.1.1.2 14-Bit ADC
            1. 8.3.1.1.2.1 Optional Real-Time Calibration Using the Host Microcontroller
          3. 8.3.1.1.3 16-Bit CC
          4. 8.3.1.1.4 External Thermistor
          5. 8.3.1.1.5 Die Temperature Monitor
          6. 8.3.1.1.6 16-Bit Pack Voltage
          7. 8.3.1.1.7 System Scheduler
        2. 8.3.1.2 Protection Subsystem
          1. 8.3.1.2.1 Integrated Hardware Protections
          2. 8.3.1.2.2 Reduced Test Time
        3. 8.3.1.3 Control Subsystem
          1. 8.3.1.3.1 FET Driving (CHG AND DSG)
            1. 8.3.1.3.1.1 High-Side FET Driving
          2. 8.3.1.3.2 Load Detection
          3. 8.3.1.3.3 Cell Balancing
          4. 8.3.1.3.4 Alert
          5. 8.3.1.3.5 Output LDO
        4. 8.3.1.4 Communications Subsystem
    4. 8.4 Device Functional Modes
      1. 8.4.1 NORMAL Mode
      2. 8.4.2 SHIP Mode
    5. 8.5 Register Maps
      1. 8.5.1 Register Details
      2. 8.5.2 Read-Only Registers
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Device Timing
      2. 9.1.2 Random Cell Connection
      3. 9.1.3 Power Pin Diodes
      4. 9.1.4 Alert Pin
      5. 9.1.5 Sense Inputs
      6. 9.1.6 TSn Pins
      7. 9.1.7 Unused Pins
      8. 9.1.8 Configuring Alternative Cell Counts
    2. 9.2 Typical Applications
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Step-by-Step Design Procedure
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Third-Party Products Disclaimer
    2. 12.2 Documentation Support
    3. 12.3 Related Links
    4. 12.4 Receiving Notification of Documentation Updates
    5. 12.5 Trademarks
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information
8.3.1.1.5 Die Temperature Monitor
Note:

When switching between external and internal temperature monitoring, a 2-s latency may be incurred due to the natural scheduler update interval.

A die temperature block generates a voltage that is proportional to the die temperature, and provides a way of reducing component count if pack thermistors are not used or ensuring that the die power dissipation requirements are observed. The die is measured using the same on-board 14-bit ADC as the cell voltages.

To select internal die temperature measurement mode, set [TEMP_SEL] = 0.

For BQ76930 and BQ76940, multiple die temperature measurements are available. These are stored in TS2 and TS3.

To convert a DIETEMP reading into temperature, refer to the following equation box. If more accurate temperature readings are needed from DIETEMP, the DIETEMP at room temperature value should be stored during production calibration.

The following equation shows how to use the 14-bit ADC readings in TS1, TS2, and TS3 when [TEMPSEL] = 0 to determine the internal die temperature:


Equation 6. V25 = 1.200 V (nominal)
Equation 7. VTSX = (ADC in Decimal) x 382 µV/LSB
Equation 8. TEMPDIE = 25° – ((VTSX – V25) ÷ 0.0042)