TIDUFG6A December   2025  – June 2026

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
    1. 1.1 Terminology
    2. 1.2 Key System and Interface Specifications
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
    3. 2.3 Highlighted Products
      1. 2.3.1 TMS320F28P65x (F28P65x)
      2. 2.3.2 DRV8376
      3. 2.3.3 DP83826A
  9. 3System Design Theory
    1. 3.1 F28P65 Motor Control and Communication Interface
    2. 3.2 Multi-Axis Motor Control Scheme
    3. 3.3 DC Link Decoupling
    4. 3.4 Three-Phase Inverter With DRV8376
    5. 3.5 System Power Management
    6. 3.6 Ethernet Physical Layer
  10. 4Hardware, Software, Testing Requirements, and Test Results
    1. 4.1 Hardware Requirements
      1. 4.1.1 TIDA-010992 PCB Overview
      2. 4.1.2 TIDA-010992 Hardware Settings
    2. 4.2 Software Requirements
    3. 4.3 Testing and Results
      1. 4.3.1 Power Management and System Power Up and Power Down
      2. 4.3.2 Current Feedback
      3. 4.3.3 Three-Phase Half-Bridge Motor Driver Power Stage Switch Node
      4. 4.3.4 Multi-Axis Motor Control Scheme Verification
      5. 4.3.5 System Thermal Measurements
  11. 5Design and Documentation Support
    1. 5.1 Design Files
      1. 5.1.1 Schematics
      2. 5.1.2 BOM
      3. 5.1.3 Layer plots
      4. 5.1.4 Altium Project
      5. 5.1.5 Gerber Files
      6. 5.1.6 Assembly Drawings
    2. 5.2 Tools and Software
    3. 5.3 Documentation Support
    4. 5.4 Support Resources
    5.     Trademarks
  12. 6About the Author
  13. 7Revision History

4.3.2 Current Feedback

The three-phase current per axis are sensed using an integrated current sensing feature eliminating the need for external sense resistors and then feedbacking the current data to three ADC modules inside the MCU to ensure simultaneous sensing. Figure 4-8 shows the current sense sampling with 16kHz PWM frequency with no-load motor. The peak ripple current is around 1A and the RMS ripple current per PWM cycle is around 214mA. Figure 4-9 shows the current sense sampling with 50kHz PWM frequency. The peak ripple current is around 250mA and the RMS ripple current per PWM cycle is around 98mA. From the comparison test results, we can see the motor ripple current reduced significantly with the PWM switching frequency increasing. To have better motor control performance and avoid over-heating the motor, 64kHz PWM switching frequency is implemented for this reference design. The motor type of humanoid hand is all coreless motor with very small inductance. So, the control PWM switching frequency should be set at more than 50kHz.

TIDA-010992 TIDA-010992 Current Sense Sampling With 16kHz PWM Figure 4-8 TIDA-010992 Current Sense Sampling With 16kHz PWM
TIDA-010992 TIDA-010992 Current Sense Sampling With 50kHz PWM Figure 4-9 TIDA-010992 Current Sense Sampling With 50kHz PWM