SLUUCJ6 November   2023

 

  1.   1
  2.   BQ76907 Evaluation Module
  3.   Trademarks
  4. 1Features
    1. 1.1 Kit Contents
    2. 1.2 Ordering Information
    3. 1.3 BQ76907 Circuit Module Performance Specification Summary
    4. 1.4 Required Equipment
  5. 2BQ76907 EVM Quick Start Guide
    1. 2.1 Before You Begin
    2. 2.2 Quick Start
  6. 3Battery Management Studio Software
    1. 3.1 System Requirements
    2. 3.2 Installing BQStudio
    3. 3.3 BQ76907 bqz File Installation
    4. 3.4 BQStudio Operation and Registers View
    5. 3.5 Commands
    6. 3.6 Data Memory
      1. 3.6.1 Entering, Saving, and Loading Configuration
    7. 3.7 Command Sequences
  7. 4BQ76907 Circuit Module Use
    1. 4.1 Cell Simulator
    2. 4.2 Evaluating with Load Current
    3. 4.3 Evaluating Charge and Discharge Currents
    4. 4.4 Evaluating with Simulated Current
    5. 4.5 Reducing the Cell Count
    6. 4.6 Connecting Cells
    7. 4.7 Connecting to a Host
    8. 4.8 Hardware Configuration
      1. 4.8.1 Configuration Jumpers
    9. 4.9 Configuration Register Programming
  8. 5BQ76907EVM Circuit Module Physical Construction
    1. 5.1 Board Layout
    2. 5.2 Bill of Materials
    3. 5.3 Schematic

4.6 Connecting Cells

The EVM is constructed with a single connection to the top and bottom of the cell stack. Cell voltage for these cells is sensed on the board.

The cell simulator provides resistors between the cell inputs. When the cell simulator shunts are installed, these resistors will load the cells and divide the voltage to any unconnected inputs as cells are connected. If desired, the cell simulator shunts can be installed during cell connection and removed after cell connection. The cell simulator shunts must be removed after connection of cells or the cells will be discharged by the constant drain of the cell simulator resistors.

BAT- is the reference voltage for the IC and it is recommended to be connected first. After BAT- cells may be connected in any order. Cell connection from the bottom up minimizes the voltage step size applied to the board. Recommended connection sequence for the EVM when connecting cells is bottom up:

  1. Connect BAT–
  2. Connect cells bottom up; CELL1, CELL2, CELL3 ...
  3. Be sure the cell simulator shunts are removed

Figure 4-5 shows an example connecting cells with an EVM configuration reduced to 6 cells.

GUID-20220718-SS0I-GFSP-40N7-PPWGWMDNGQNK-low.svgFigure 4-5 Example Connection with 6 Cells