SLVSHH5A August   2023  – October 2023 TPS25983

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Device Comparison Table
  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 Timing Requirements
    7. 7.7 Switching Characteristics
    8. 7.8 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 (UVLO and UVP)
      2. 8.3.2 Overvoltage Protection (OVP)
      3. 8.3.3 Inrush Current, Overcurrent, and Short-Circuit Protection
        1. 8.3.3.1 Slew Rate and Inrush Current Control (dVdt)
        2. 8.3.3.2 Circuit Breaker
        3. 8.3.3.3 Active Current Limiting
        4. 8.3.3.4 Short-Circuit Protection
      4. 8.3.4 Overtemperature Protection (OTP)
      5. 8.3.5 Analog Load Current Monitor (IMON)
      6. 8.3.6 Power Good (PG)
      7. 8.3.7 Reverse Current Blocking FET Driver
      8. 8.3.8 Fault Response
    4. 8.4 Device Functional Modes
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application: Standby Power Rail Protection in Datacenter Servers
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Device Selection
        2. 9.2.2.2 Setting the Current Limit Threshold: RILIM Selection
        3. 9.2.2.3 Setting the Undervoltage and Overvoltage Lockout Set Point
        4. 9.2.2.4 Choosing the Current Monitoring Resistor: RIMON
        5. 9.2.2.5 Setting the Output Voltage Ramp Time (TdVdt)
          1. 9.2.2.5.1 Case 1: Start-Up Without Load: Only Output Capacitance COUT Draws Current
          2. 9.2.2.5.2 Case 2: Start-Up With Load: Output Capacitance COUT and Load Draw Current
        6. 9.2.2.6 Setting the Transient Overcurrent Blanking Interval (tITIMER)
        7. 9.2.2.7 Setting the Auto-Retry Delay and Number of Retries
      3. 9.2.3 Application Curves
    3. 9.3 System Examples
      1. 9.3.1 Optical Module Power Rail Path Protection
        1. 9.3.1.1 Design Requirements
        2. 9.3.1.2 Device Selection
        3. 9.3.1.3 External Component Settings
        4. 9.3.1.4 Voltage Drop
        5. 9.3.1.5 Application Curves
      2. 9.3.2 Input Protection for 12-V Rail Applications: PCIe Cards, Storage Interfaces, and DC Fans
      3. 9.3.3 Priority Power MUXing
    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 Receiving Notification of Documentation Updates
    3. 10.3 Support Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

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

8.3.7 Reverse Current Blocking FET Driver

TPS25983 provides an option to drive an external N-FET for implementing reverse current blocking function. The N-FET is connected in series with the eFuse in a common source configuration as shown in Figure 8-8. The gate of the blocking FET is controlled by the dVdt/BGATE pin of the eFuse. When the eFuse is turned ON and operating in steady-state, the dVdt/BGATE is driven high which turns the external FET fully ON to provide a low-impedance power path from input to output. When the eFuse turns OFF under any condition, the dVdt/BGATE pin is pulled low and the blocking FET is turned OFF. This behavior makes sure that there is no current path from the output to input in the OFF state.

GUID-20230731-SS0I-H3R7-FZ6Q-M2HJTFSKZFV6-low.svg Figure 8-8 Reverse Current Blocking Using External FET

Figure 8-9 shows an example of TPS25983 reverse current blocking response. When the input supply is disconnected, there is some reverse current flow as the input supply start falling and the output capacitance also discharges initially. Once the input supply voltage falls low enough to trigger the undervoltage response, the device turns OFF the external FET to block the reverse current completely.

GUID-20230731-SS0I-ZFM5-KNJK-SWNXD19TMS1K-low.svgFigure 8-9 Reverse Current Blocking Response