TIDUF82A August   2024  – November 2024 DRV8162 , INA241A , ISOM8710

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
    1. 1.1 Reference Design Overview
    2. 1.2 Key System Specifications
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
      1. 2.2.1 Hardware Design
        1. 2.2.1.1 Power Stage Gate Driver
          1. 2.2.1.1.1 Gate Driver
          2. 2.2.1.1.2 Protection Features
          3. 2.2.1.1.3 VGVDD Definition
          4. 2.2.1.1.4 Strap Functions
        2. 2.2.1.2 Power Stage FETs
          1. 2.2.1.2.1 VGS versus RDS(ON)
        3. 2.2.1.3 Phase Current and Voltage Sensing
          1. 2.2.1.3.1 Phase Current
          2. 2.2.1.3.2 Phase Current – Bias Voltage Reference
          3. 2.2.1.3.3 Voltage
        4. 2.2.1.4 Host Processor Interface
        5. 2.2.1.5 Gate Drive Shutdown Path
        6. 2.2.1.6 System Diagnostic Measurements
          1. 2.2.1.6.1 Temperature Measurement
        7. 2.2.1.7 System Power Supply
          1. 2.2.1.7.1 12V Rail
          2. 2.2.1.7.2 3.3V Rail
      2. 2.2.2 Software Design
    3. 2.3 Highlighted Products
      1. 2.3.1 DRV8162L
      2. 2.3.2 INA241A
      3. 2.3.3 LMR38010
      4. 2.3.4 TMP6131
      5. 2.3.5 ISOM8710
  9. 3Hardware, Software Test Requirements and Test Results
    1. 3.1 Hardware Requirements
      1. 3.1.1 PCB Overview
      2. 3.1.2 Hardware Configuration
        1. 3.1.2.1 Prerequisites
        2. 3.1.2.2 Default Resistor and Jumper Configuration
        3. 3.1.2.3 Connector
          1. 3.1.2.3.1 Host Processor Interface
    2. 3.2 Test Setup
    3. 3.3 Test Results
      1. 3.3.1 Power Management
        1. 3.3.1.1 Power Up
        2. 3.3.1.2 Power Down
      2. 3.3.2 Gate Voltage and Phase Voltage
        1. 3.3.2.1 20 VDC
        2. 3.3.2.2 48 VDC
        3. 3.3.2.3 60 VDC
      3. 3.3.3 Digital PWM and Gate Voltage
      4. 3.3.4 Phase-Current Measurements
      5. 3.3.5 System Test Results
        1. 3.3.5.1 Thermal Analysis
  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 Authors
  12. 6Revision History

3.3.2 Gate Voltage and Phase Voltage

To measure the gate voltage and the phase voltage on the switch node, the following measurements were performed. Figure 3-6 shows the test setup.

TIDA-010956 Test Setup for the Gate Voltage and Switch Node Voltage Measurements Figure 3-6 Test Setup for the Gate Voltage and Switch Node Voltage Measurements

In these tests the VDC applied was 48V and the motor was set to a fixed angle with open loop vector control. The signals were measured in phase-B, including the gate voltage (CH1, in dark blue) of the low-side MOSFET, the switch node voltage (CH2, in light blue) of the phase, and the output current (CH4, in green). Both voltages are referenced to GND and the positive direction of the phase current is from the drive to the motor.

The measurements in Section 3.3.2.1, Section 3.3.2.2, and Section 3.3.2.3 show the shifts of the phase in the conditions when the current was set to both positive and negative values. All four configurations of soft switching and hard switching of the low-side MOSFET were measured.