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)

10.1 Layout Guidelines

Designers must pay close attention to PCB layout to achieve optimum performance for the UCC23525. Some key guidelines are:

  • Component placement:
    • Low-ESR and low-ESL capacitors must be connected close to the device between the VDD and VSS pins to bypass noise and to support high peak currents when turning on the external power transistor.
    • To avoid large negative transients on the VSS pins connected to the switch node, the parasitic inductances between the source of the top transistor and the source of the bottom transistor must be minimized.
  • Grounding considerations:
    • Limiting the high peak currents that charge and discharge the transistor gates to a minimal physical area is essential. This limitation decreases the loop inductance and minimizes noise on the gate terminals of the transistors. The gate driver must be placed as close as possible to the transistors.
  • High-voltage considerations:
    • To ensure isolation performance between the primary and secondary side, avoid placing any PCB traces or copper below the driver device. A PCB cutout or groove is recommended in order to prevent contamination that may compromise the isolation performance.
  • Thermal considerations:
    • A large amount of power may be dissipated by the UCC23525 if the driving voltage is high, the load is heavy, or the switching frequency is high. Proper PCB layout can help dissipate heat from the device to the PCB and minimize junction-to-board thermal impedance (θJB).
    • Increasing the PCB copper connecting to the VDD and VSS pins is recommended, with priority on maximizing the connection to VSS. However, the previously mentioned high-voltage PCB considerations must be maintained.
    • If the system has multiple layers, TI also recommends connecting the VDD and VSS pins to internal ground or power planes through multiple vias of adequate size. These vias should be located close to the IC pins to maximize thermal conductivity. However, keep in mind that no traces or coppers from different high voltage planes are overlapping.