SLVSGX1A July   2023  – October 2023 TPS25984

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Description (continued)
  7. 6 Pin Configuration and Functions
  8. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Logic Interface
    7. 7.7 Timing Requirements
    8. 7.8 Switching Characteristics
    9. 7.9 Typical Characteristics
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Undervoltage Protection
      2. 8.3.2  Insertion Delay
      3. 8.3.3  Overvoltage Protection
      4. 8.3.4  Inrush Current, Overcurrent, and Short-Circuit Protection
        1. 8.3.4.1 Slew Rate (dVdt) and Inrush Current Control
          1. 8.3.4.1.1 Start-Up Time Out
        2. 8.3.4.2 Steady-State Overcurrent Protection (Circuit-Breaker)
        3. 8.3.4.3 Active Current Limiting During Start-Up
        4. 8.3.4.4 Short-Circuit Protection
      5. 8.3.5  Analog Load Current Monitor (IMON)
      6. 8.3.6  Mode Selection (MODE)
      7. 8.3.7  Parallel Device Synchronization (SWEN)
      8. 8.3.8  Stacking Multiple eFuses for Unlimited Scalability
        1. 8.3.8.1 Current Balancing During Start-Up
      9. 8.3.9  Analog Junction Temperature Monitor (TEMP)
      10. 8.3.10 Overtemperature Protection
      11. 8.3.11 Fault Response and Indication (FLT)
      12. 8.3.12 Power-Good Indication (PG)
      13. 8.3.13 Output Discharge
      14. 8.3.14 FET Health Monitoring
      15. 8.3.15 Single Point Failure Mitigation
        1. 8.3.15.1 IMON Pin Single Point Failure
        2. 8.3.15.2 ILIM Pin Single Point Failure
        3. 8.3.15.3 IREF Pin Single Point Failure
        4. 8.3.15.4 ITIMER Pin Single Point Failure
    4. 8.4 Device Functional Modes
  10. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Single Device, Standalone Operation
      2. 9.1.2 Multiple Devices, Parallel Connection
      3. 9.1.3 Multiple eFuses, Parallel Connection With PMBus
      4. 9.1.4 Digital Telemetry Using External Microcontroller
    2. 9.2 Typical Application: 12-V, 3.3-kW Power Path Protection in Data Center Servers
      1. 9.2.1 Application
      2. 9.2.2 Design Requirements
      3. 9.2.3 Detailed Design Procedure
      4. 9.2.4 Application Curves
    3. 9.3 Best Design Practices
    4. 9.4 Power Supply Recommendations
      1. 9.4.1 Transient Protection
      2. 9.4.2 Output short-Circuit Measurements
    5. 9.5 Layout
      1. 9.5.1 Layout Guidelines
      2. 9.5.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Documentation Support
      1. 10.1.1 Related Documentation
    2. 10.2 Support Resources
    3. 10.3 Trademarks
    4. 10.4 Electrostatic Discharge Caution
    5. 10.5 Glossary
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

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

8.3.4.1 Slew Rate (dVdt) and Inrush Current Control

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 managed properly, the inrush current can damage the input connectors and cause the system power supply to droop. This action can lead to unexpected restarts elsewhere in the system. The inrush current during turn-on is directly proportional to the load capacitance and rising slew rate. Equation 2 can be used to find the slew rate (SR) required to limit the inrush current (IINRUSH) for a given load capacitance (CLOAD):

Equation 2. S R V / m s = I I N R U S H A C L O A D m F

A capacitor can be added to the dVdt 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 Equation 3.

Equation 3. CDVDTpF=42000SRV/ms

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

Note:
  1. High input slew rates in combination with high input power path inductance can result in oscillations during start-up. This can be mitigated using one or more of the following steps:
    1. Reduce the input inductance.
    2. Increase the capacitance on VIN pin.
    3. Increase the dVdt pin capacitance to reduce the slew rate or increase the start-up time. TI recommends using a minimum start-up time of 5 ms.