SLVSHR6A July   2025  – November 2025 TPS1686

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 Logic Interface
    7. 6.7 Timing Requirements
    8. 6.8 Switching Characteristics
    9. 6.9 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
      2. 7.3.2  Insertion Delay
      3. 7.3.3  Overvoltage Protection
      4. 7.3.4  Inrush Current, Overcurrent, and Short-Circuit Protection
        1. 7.3.4.1 Slew Rate (dVdt) and Inrush Current Control
          1. 7.3.4.1.1 Start-Up Time Out
        2. 7.3.4.2 Steady-State Overcurrent Protection (circuit-breaker)
        3. 7.3.4.3 Active Current Limiting During Start-Up
        4. 7.3.4.4 Short-Circuit Protection
      5. 7.3.5  Analog Load Current Monitor (IMON)
      6. 7.3.6  Switch Enable Pin (SWEN)
      7. 7.3.7  Analog Junction Temperature Monitor (TEMP)
      8. 7.3.8  Overtemperature Protection
      9. 7.3.9  Fault Response and Indication (FLT)
      10. 7.3.10 Power Good Indication (PG)
      11. 7.3.11 Output Discharge
      12. 7.3.12 FET Health Monitoring
      13. 7.3.13 Single Point Failure Mitigation
        1. 7.3.13.1 IMON Pin Single Point Failure
        2. 7.3.13.2 IREF Pin Single Point Failure
        3. 7.3.13.3 ITIMER Pin Single Point Failure
    4. 7.4 Device Functional Modes
  9. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Single Device, Standalone Operation
    2. 8.2 Typical Application: 54V Fan Load Protection in Datacenter Servers
      1. 8.2.1 Application
      2. 8.2.2 Design Requirements
      3. 8.2.3 Detailed Design Procedure
      4. 8.2.4 Application Performance Plots
    3. 8.3 Power Supply Recommendations
      1. 8.3.1 Transient Protection
      2. 8.3.2 Output Short-Circuit Measurements
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Third-Party Products Disclaimer
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
    3. 9.3 Receiving Notification of Documentation Updates
    4. 9.4 Support Resources
    5. 9.5 Trademarks
    6. 9.6 Electrostatic Discharge Caution
    7. 9.7 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

7.3.4.4 Short-Circuit Protection

During an output short-circuit event, the current through the device increases very rapidly. When an output short-circuit is detected, the internal fast-trip comparator triggers a fast protection sequence to prevent the current from building up further and causing any damage or excessive input supply droop. The fast-trip comparator employs a scalable threshold (ISFT) during steady-state . ISFT can be selected by resistor on SFT_SEL pin. This enables the user to adjust the fast-trip threshold as per system rating, rather than using a high fixed threshold which is not always suitable for all systems. After the current exceeds the fast-trip threshold, the TPS1686x turns off the FET within tSFT. The device also employs a higher fixed fast-trip threshold (IFFT) to provide fast protection against hard short-circuits during steady-state (FET in linear region). After the current exceeds IFFT, the FET is turned off completely within tFFT.

Table 7-1 Device Functional Modes Based on Resistor on SFT_SEL Pin

ISFT_SEL

 SFT_SEL PIN

IOC_BKP

RSFT_SEL <95kΩ

2.5 x IOCP

105kΩ < RSFT_SEL < 195kΩ

2 xIOCP

 205kΩ < RSFT_SEL < 295kΩ

1.5 xIOCP

 305kΩ < RSFT_SEL