SLUSF58A December   2023  – April 2024 UCC23525

ADVANCE INFORMATION  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Function
  6. 5 Specifications
    1. 5.1  Absolute Maximum Ratings
    2. 5.2  ESD Ratings
    3. 5.3  Recommended Operating Conditions
    4. 5.4  Thermal Information
    5. 5.5  Power Ratings
    6. 5.6  Insulation Specifications
    7. 5.7  Safety Limiting Values
    8. 5.8  Electrical Characteristics
    9. 5.9  Switching Characteristics
    10. 5.10 Thermal Derating Curves
    11. 5.11 Typical Characteristics
  7. 6 Parameter Measurement Information
    1. 6.1 Propagation Delay, Rise Time and Fall Time
    2. 6.2 IOH and IOL Testing
    3. 6.3 CMTI Testing
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Power Supply
      2. 7.3.2 Input Stage
      3. 7.3.3 Output Stage
      4. 7.3.4 Protection Features
        1. 7.3.4.1 Undervoltage Lockout (UVLO)
        2. 7.3.4.2 Active Pulldown
        3. 7.3.4.3 Short-Circuit Clamping
        4. 7.3.4.4 ESD Structure
    4. 7.4 Device Functional Modes
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Selecting the Input Resistor
        2. 8.2.2.2 Gate Driver Output Resistor
        3. 8.2.2.3 Estimate Gate-Driver Power Loss
        4. 8.2.2.4 Estimating Junction Temperature
        5. 8.2.2.5 Selecting VDD Capacitor
  10. 9 Power Supply Recommendations
  11. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 PCB Material
  12. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Support Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  13. 12Revision History
  14. 13Mechanical, Packaging, and Orderable Information
    1. 13.1 Package Option Addendum
    2. 13.2 Tape and Reel Information
    3. 13.3 Mechanical Data

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • DWY|6
Thermal pad, mechanical data (Package|Pins)

7.3.2 Input Stage

The input stage of UCC23525 is simply the e-diode and therefore has an Anode (Pin 1) and a Cathode (Pin 3). Pin 2 has no internal connection and can be left open or connected to ground. The input stage does not have a power and ground pin. When the e-diode is forward biased by applying a positive voltage to the Anode with respect to the Cathode, a forward current IF flows into the e-diode. The forward voltage drop across the e-diode is 1.7V (typ). An external resistor should be used to limit the forward current. The recommended range for the forward current is 5mA to 20mA. When IF exceeds the threshold current IFLH(1mA typ.) a high frequency signal is transmitted across the isolation barrier. The HF signal is detected by the receiver and VOUT is driven high. See Section 8.2.2.1 for information on selecting the input resistor. The dynamic impedance of the e-diode is very small(<1.0Ω) and the temperature coefficient of the e-diode forward voltage drop is <0.7mV/°C. This leads to excellent stability of the forward current IF across all operating conditions. If the Anode voltage drops below VF_HL (0.8V), or reverse biased, the gate driver output is driven low. The reverse breakdown voltage of the e-diode is >6V. So for normal operation, a reverse bias of up to 5V is allowed. The large reverse breakdown voltage of the e-diode enables UCC23525 to be operated in interlock architecture (see example in Figure 7-3) where VSUP can be as high as 5V. The system designer has the flexibility to choose a 3.3V or 5.0V signal source to drive the input stage of UCC23525 using an appropriate input resistor. The example shows two gate drivers driving a set of IGBTs. The inputs of the gate drivers are connected as shown and driven by two buffers that are controlled by the microcontroller unit (MCU). Interlock architecture prevents both the e-diodes from being "ON" at the same time, preventing shoot through in the IGBTs. It also ensures that if both PWM signals are erroneously stuck high (or low) simultaneously, both gate driver outputs will be driven low.

GUID-20231214-SS0I-KTKB-HHT9-LXNXKCQWTWMF-low.svg Figure 7-3 Interlock