SDAA370 May   2026 UCC34141

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
    1. 1.1 End-Equipment Traction Inverter
    2. 1.2 Why is Safety Needed in Inverter?
    3. 1.3 FuSa Development Flow
      1. 1.3.1 V-Model Development
      2. 1.3.2 Inverter Safety Lifecycle
  5. 2FuSa Requirements for Traction Inverter
    1. 2.1 Traction Inverter Structure and Function Introduction
    2. 2.2 FuSa Requirements Derivation Process
    3. 2.3 Safety Goal
    4. 2.4 FuSa Concept
      1. 2.4.1 FSC Design Architecture
      2. 2.4.2 Fault Tree Analysis
      3. 2.4.3 FuSa Requirement
    5. 2.5 Technical Safety Concepts
      1. 2.5.1 TSC Design Architecture
      2. 2.5.2 Failure Mode and Effect Analysis
      3. 2.5.3 Technical Safety Requirements
  6. 3Safety Design Implementation on Inverter
    1. 3.1 TI FuSa Product
    2. 3.2 How Does TSR Implement?
      1. 3.2.1 Position Sensor
      2. 3.2.2 MCU
      3. 3.2.3 Logic Circuit
      4. 3.2.4 Smart Isolated Gate Driver
    3. 3.3 Dependent Failure Consideration
    4. 3.4 Detailed FuSa Design Structure for Traction Inverter
    5. 3.5 Achieving FuSa Requirements with TI Safety Devices
      1. 3.5.1 MCU
      2. 3.5.2 Gate Driver
        1. 3.5.2.1 Gate Monitor Circuit and Over Current Protection
        2. 3.5.2.2 Other Safety Mechanisms in UCC5881-Q1
      3. 3.5.3 Isolated bias supply
        1. 3.5.3.1 Centralized LV Isolated Power Supply Architecture
        2. 3.5.3.2 Fully Distributed LV Isolated Power Supply Architecture
        3. 3.5.3.3 Semi-Distributed LV Isolated Power Supply Architecture
        4. 3.5.3.4 HV Isolated Bias Supply
        5. 3.5.3.5 TI's Design for Isolated Bias Supply in Traction Inverter
      4. 3.5.4 Power Management IC
        1. 3.5.4.1 Multiple Paths Power Rail with Protection and Independent Thermal Shut-Down
        2. 3.5.4.2 Power Rail Voltage Monitoring
        3. 3.5.4.3 MCU Fault Monitor and other Protection Mechanisms
      5. 3.5.5 Position Sensor
      6. 3.5.6 Current Sensor
      7. 3.5.7 Voltage Sensor
        1. 3.5.7.1 Isolated DC Voltage Sensing
        2. 3.5.7.2 Non-Isolated DC voltage sensing
      8. 3.5.8 Temperature Sensor
  7. 4Summary
  8. 5References

3.5.2 Gate Driver

In traction inverter systems, the gate driver is assigned a high FuSa level to prevent unintended torque and over-current/shoot-through conditions in the power module. The UCC5881-Q1 is an isolated, highly configurable gate driver with adjustable drive strength specifically designed to drive high-power SiC MOSFETs and IGBTs. The ASC feature for entering safe state has been mentioned in Section 3.2.4.

Beyond ASC functionality, the UCC5881-Q1 incorporates numerous protection features including gate driver output state monitoring, soft turn-off during failure conditions, power module threshold voltage detection, overvoltage/undervoltage lockout (OV/UVLO), and shoot-through protection. The UCC5881-Q1 also supports active Miller clamp functionality to prevent unintended turn-on of the power module during high dv/dt events. Additionally, the device provides two external ADC channels to support multiple DC link voltage and power module temperature sensing paths, which is beneficial for implementing measurement redundancy while optimizing system cost.

Figure 3-11 illustrates the block diagram of the UCC5881-Q1 in a typical traction inverter application. The key protection features and safety mechanisms are listed below.

Block diagram of UCC5881-Q1 used in a typical traction inverter Figure 3-11 Block diagram of UCC5881-Q1 used in a typical traction inverter