SLVSHH5B August   2023  – December 2024 TPS25983

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and 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 Electrical Characteristics
    6. 6.6 Timing Requirements
    7. 6.7 Switching Characteristics
    8. 6.8 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Undervoltage Protection (UVLO and UVP)
      2. 7.3.2 Overvoltage Protection (OVP)
      3. 7.3.3 Inrush Current, Overcurrent, and Short-Circuit Protection
        1. 7.3.3.1 Slew Rate and Inrush Current Control (dVdt)
        2. 7.3.3.2 Circuit Breaker
        3. 7.3.3.3 Active Current Limiting
        4. 7.3.3.4 Short-Circuit Protection
      4. 7.3.4 Overtemperature Protection (OTP)
      5. 7.3.5 Analog Load Current Monitor (IMON)
      6. 7.3.6 Power Good (PG)
      7. 7.3.7 Reverse Current Blocking FET Driver
      8. 7.3.8 Fault Response
    4. 7.4 Device Functional Modes
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application: Standby Power Rail Protection in Datacenter Servers
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Device Selection
        2. 8.2.2.2 Setting the Current Limit Threshold: RILIM Selection
        3. 8.2.2.3 Setting the Undervoltage and Overvoltage Lockout Set Point
        4. 8.2.2.4 Choosing the Current Monitoring Resistor: RIMON
        5. 8.2.2.5 Setting the Output Voltage Ramp Time (TdVdt)
          1. 8.2.2.5.1 Case 1: Start-Up Without Load: Only Output Capacitance COUT Draws Current
          2. 8.2.2.5.2 Case 2: Start-Up With Load: Output Capacitance COUT and Load Draw Current
        6. 8.2.2.6 Setting the Transient Overcurrent Blanking Interval (tITIMER)
        7. 8.2.2.7 Setting the Auto-Retry Delay and Number of Retries
      3. 8.2.3 Application Curves
    3. 8.3 System Examples
      1. 8.3.1 Optical Module Power Rail Path Protection
        1. 8.3.1.1 Design Requirements
        2. 8.3.1.2 Device Selection
        3. 8.3.1.3 External Component Settings
        4. 8.3.1.4 Voltage Drop
        5. 8.3.1.5 Application Curves
      2. 8.3.2 Input Protection for 12-V Rail Applications: PCIe Cards, Storage Interfaces, and DC Fans
      3. 8.3.3 Priority Power MUXing
    4. 8.4 Power Supply Recommendations
      1. 8.4.1 Transient Protection
      2. 8.4.2 Output Short-Circuit Measurements
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
      2. 8.5.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Documentation Support
      1. 9.1.1 Related Documentation
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7.3.3.1 Slew Rate and Inrush Current Control (dVdt)

During hot-plug events or while trying to charge a large output capacitance, there can be a large inrush current. If the inrush current is not controlled, it can damage the input connectors and/or cause the system power supply to droop leading to unexpected restarts elsewhere in the system. The TPS25983 provides integrated output slew rate (dVdt) control to manage the inrush current during start-up. The inrush current is directly proportional to the load capacitance and rising slew rate. The following equation can be used to calculate the slew rate (SR) required to limit the inrush current (IINRUSH) for a given load capacitance (COUT):

Equation 3. TPS25983

An external capacitance can be connected to the dVdt/BGATE pin to control the rising slew rate and lower the inrush current during turn on. The required CdVdt capacitance to produce a given slew rate can be calculated using the following formula:

Equation 4. TPS25983

The fastest output slew rate is achieved by leaving the dVdt/BGATE pin open.