SLUUCY9 November   2023 BQ76905

 

  1.   1
  2.   Description
  3.   Get Started
  4.   Features
  5.   Applications
  6.   6
  7. 1Evaluation Module Overview
    1. 1.1 Introduction
    2. 1.2 Kit Contents
    3. 1.3 Specification
    4. 1.4 Device Information
  8. 2Hardware
    1. 2.1 Before You Begin
    2. 2.2 Required Equipment
    3. 2.3 BQ76905 Circuit Module Use
      1. 2.3.1 Cell Simulator
      2. 2.3.2 Evaluating with Load Current
      3. 2.3.3 Evaluating Charge and Discharge Currents
      4. 2.3.4 Evaluating with Simulated Current
      5. 2.3.5 Reducing the Cell Count
      6. 2.3.6 Connecting Cells
      7. 2.3.7 Connecting to a Host
      8. 2.3.8 Hardware Configuration
        1. 2.3.8.1 Configuration Jumpers
      9. 2.3.9 Configuration Register Programming
  9. 3Quick Start Guide
  10. 4Software
    1. 4.1 Battery Management Studio Software
      1. 4.1.1 System Requirements
      2. 4.1.2 Installing BQStudio
      3. 4.1.3 BQ76905 bqz File Installation
      4. 4.1.4 BQStudio Operation and Registers View
      5. 4.1.5 Commands
      6. 4.1.6 Data Memory
        1. 4.1.6.1 Entering, Saving, and Loading Configuration
      7. 4.1.7 Command Sequences
  11. 5Hardware Design Files
    1. 5.1 Schematic
    2. 5.2 Board Layout
    3. 5.3 Bill of Materials
  12. 6Additional Information
    1.     Trademarks

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

BAT- is the reference voltage for the IC and must be connected first. After BAT- cells can 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 3-5 shows an example connecting cells with an EVM configuration reduced to 4 cells.

GUID-20231117-SS0I-TZBS-K3B9-CG493WJHSN65-low.svg Figure 2-5 Example Connection with 4 Cells