TIDUEY0A November   2020  – December 2025

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
    1. 1.1 Li-ion Cell Formation Equipment
    2. 1.2 Key System Specifications
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 System Design Theory
      1. 2.2.1 Feedback Controller
      2. 2.2.2 DC/DC Start-Up
      3. 2.2.3 High-Resolution PWM Generation
      4. 2.2.4 Output Inductor and Capacitor Selection
      5. 2.2.5 Current and Voltage Feedback
    3. 2.3 Highlighted Products
      1. 2.3.1 TMS320F28P650DK
      2. 2.3.2 ADS9324
      3. 2.3.3 INA630
      4. 2.3.4 UCC27284
      5. 2.3.5 REF50E
  9. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Hardware Requirements
    2. 3.2 Software
      1. 3.2.1 Opening the Project Inside Code Composer Studio
      2. 3.2.2 Project Structure
      3. 3.2.3 Software Flow Diagram
    3. 3.3 Test Setup
      1. 3.3.1 Hardware Setup to Test Bidirectional Power Flow
      2. 3.3.2 Hardware Setup to Tune the Current and Voltage Loop
      3. 3.3.3 Hardware Setup for Current and Voltage Calibration
      4. 3.3.4 Lab Variables Definitions
      5. 3.3.5 Test Procedure
        1. 3.3.5.1 Lab 1. Open-Loop Current Control Single Phase
          1. 3.3.5.1.1 Setting Software Options for Lab 1
          2. 3.3.5.1.2 Building and Loading the Project and Setting up Debug Environment
          3. 3.3.5.1.3 Running the Code
        2. 3.3.5.2 Lab 2. Closed Loop Current Control Single Channel
          1. 3.3.5.2.1 Setting Software Options for Lab 2
          2. 3.3.5.2.2 Building and Loading the Project and Setting up Debug Environment
          3. 3.3.5.2.3 Run the Code
        3. 3.3.5.3 Lab 3. Open Loop Voltage Control Single Channel
          1. 3.3.5.3.1 Setting Software Options for Lab 3
          2. 3.3.5.3.2 Building and Loading the Project and Setting up Debug Environment
          3. 3.3.5.3.3 Running the Code
        4. 3.3.5.4 Lab 4. Closed Loop Current and Voltage Control Single Channel
          1. 3.3.5.4.1 Setting Software Options for Lab 4
          2. 3.3.5.4.2 Building and Loading the Project and Setting up Debug Environment
          3. 3.3.5.4.3 Running the Code
        5. 3.3.5.5 Lab 5. Closed Loop Current and Voltage Control Four Channels
          1. 3.3.5.5.1 Setting Software Options for Lab 5
          2. 3.3.5.5.2 Building and Loading the Project and Setting up Debug Environment
          3. 3.3.5.5.3 Running the Code
        6. 3.3.5.6 Calibration
    4. 3.4 Test Results
      1. 3.4.1 Current Load Regulation
      2. 3.4.2 Voltage Load Regulation
      3. 3.4.3 Current Linearity Test
      4. 3.4.4 Voltage Loop Linearity Test
      5. 3.4.5 Bidirectional Current Switching Time
      6. 3.4.6 Current Step Response
  10. 4Design and Documentation Support
    1. 4.1 Design Files
      1. 4.1.1 Schematics
      2. 4.1.2 BOM
    2. 4.2 Tools and Software
    3. 4.3 Documentation Support
    4. 4.4 Support Resources
    5. 4.5 Trademarks
  11. 5About the Author
  12. 6Revision History

3.4.3 Current Linearity Test

The current control accuracy depends on the current-sensing resistor, the gain, offset, and drift of the current sense amplifier. The test applies two-point calibration in charging mode. The overall current error remains below ±0.02% after calibration. Figure 3-35 shows the results.

TIDA-010086 Current Control Accuracy Test Figure 3-35 Current Control Accuracy Test