SLUSDE1E September   2018  – November 2024 UCC21540 , UCC21540A , UCC21541 , UCC21542

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
    1. 5.1 Pin Configuration and Functions
    2. 5.2 UCC21542 Pin Functions
  7. 6 Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  Recommended Operating Conditions
    4. 6.4  Thermal Information
    5. 6.5  Power Ratings
    6. 6.6  Insulation Specifications
    7. 6.7  Safety-Limiting Values
    8. 6.8  Electrical Characteristics
    9. 6.9  Switching Characteristics
    10. 6.10 Insulation Characteristics Curves
    11. 6.11 Typical Characteristics
  8. 7 Parameter Measurement Information
    1. 7.1 Minimum Pulses
    2. 7.2 Propagation Delay and Pulse Width Distortion
    3. 7.3 Rising and Falling Time
    4. 7.4 Input and Disable Response Time
    5. 7.5 Programmable Dead Time
    6. 7.6 Power-Up UVLO Delay to OUTPUT
    7. 7.7 CMTI Testing
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 VDD, VCCI, and Under Voltage Lock Out (UVLO)
      2. 8.3.2 Input and Output Logic Table
      3. 8.3.3 Input Stage
      4. 8.3.4 Output Stage
      5. 8.3.5 Diode Structure in the UCC2154x
    4. 8.4 Device Functional Modes
      1. 8.4.1 Disable Pin
      2. 8.4.2 Programmable Dead Time (DT) Pin
        1. 8.4.2.1 DT Pin Tied to VCCI
        2. 8.4.2.2 Connecting a Programming Resistor between DT and GND Pins
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Designing INA/INB Input Filter
        2. 9.2.2.2 Select Dead Time Resistor and Capacitor
        3. 9.2.2.3 Select External Bootstrap Diode and Its Series Resistor
        4. 9.2.2.4 Gate Driver Output Resistor
        5. 9.2.2.5 Gate to Source Resistor Selection
        6. 9.2.2.6 Estimating Gate Driver Power Loss
        7. 9.2.2.7 Estimating Junction Temperature
        8. 9.2.2.8 Selecting VCCI, VDDA/B Capacitor
          1. 9.2.2.8.1 Selecting a VCCI Capacitor
          2. 9.2.2.8.2 Selecting a VDDA (Bootstrap) Capacitor
          3. 9.2.2.8.3 Select a VDDB Capacitor
        9. 9.2.2.9 Application Circuits with Output Stage Negative Bias
      3. 9.2.3 Application Curves
  11. 10Power Supply Recommendations
  12. 11Layout
    1. 11.1 Layout Guidelines
      1. 11.1.1 Component Placement Considerations
      2. 11.1.2 Grounding Considerations
      3. 11.1.3 High-Voltage Considerations
      4. 11.1.4 Thermal Considerations
    2. 11.2 Layout Example
  13. 12Device and Documentation Support
    1. 12.1 Third-Party Products Disclaimer
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Receiving Notification of Documentation Updates
    4. 12.4 Support Resources
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  14. 13Revision History
  15. 14Mechanical, Packaging, and Orderable Information

8.3.3 Input Stage

The input pins (INA, INB, and DIS) of the UCC2154x is based on a TTL and CMOS compatible input-threshold logic that is totally isolated from the VDD supply voltage of the output channels. The input pins are easy to drive with logic-level control signals (such as those from 3.3-V microcontrollers), since the UCC2154x has a typical high threshold (VINAH) of 1.8 V and a typical low threshold of 1 V, which vary little with temperature (see and ). A wide hysterisis (VINA_HYS) of 0.8 V makes for good noise immunity and stable operation. If any of the inputs are ever left open, internal pull-down resistors force the pin low. These resistors are typically 200 kΩ for INA/B and DIS (see Section 8.2). TI recommends grounding any unused inputs.

The amplitude of any signal applied to the inputs should not exceed the voltage at the VCCI pin. The UCC2154x cannot be driven from an analog controller with an output voltage greater than the VCCI voltage.